Bones Hi - Fi

Metal Coned Hi-Fi Loudspeakers: Wave of the Future?

2011-11-02T03:43:00.000-07:00

It is probably the stiffest cone material currently manufactured for domestic high fidelity loudspeaker use, but are metal coned hi-fi loudspeakers truly represent the future of loudspeaker design?

By: Ringo Bones

Contrary to popular belief, it does not favor playing back heavy metal rock music and while discussion still continues on the pros and cons of metal-coned drivers, the number of designers and manufacturers using them does seem to be on the increase since the late 1980s, and it is not just the bass guitar amplifier maker Hartke that’s been famed for using metal coned drivers. In the United States, Platinum, NEAR, Joseph Audio and Thiel are well-known examples while in the UK, Acoustic Energy, Monitor Audio, JPW, Studio Power, B&W (in their up-market Nautilus), Musical Technology and even Mordant Short whose up-market Performance 6 loudspeakers got very favorable reviews back in 2005. In Norway, the popular driver maker SEAS were producing a range of aluminum and magnesium alloy units since the start of the 1990s while the famed metal-dome tweeter, despite its disadvantage of an oil-can resonance between 25-KHz and 30-KHz, is still currently being used in many commercially produced hi-fi loudspeakers and is still produced by a number of manufacturers worldwide despite of the advent of high-resolution digital audio and the vinyl LP revival whose wider-than-REDBOOK-spec-CD frequency response can easily reach the oil-can resonance mode of most metal-dome tweeters. Unlike Red-Book 16-bit 44.1-KHz sampled CDs whose bandwidth stops dead at around 22-KHz.

Fundamentally, the argument for metal hi-fi loudspeaker driver cones rests on its very high stiffness with the potential avoidance of any unwanted resonance or “breakup” in these drivers’ intended working frequency range. To optimize metal cone stiffness, special alloys are used. These are physically hardened and then reinforced by electrolytic anodizing which results in a thick coating of very tough “ceramic” made from the very oxide – i.e. aluminum oxide - of the alloy itself. This anodized surface lends itself to dye coloring, as in the case of Monitor Audio’s well-known “Gold” dome back in the mid to late 1990s. Both main drivers – i.e. bass midrange cones and tweeter domes benefit from the chemical reinforcement process.

When commonly used softer cone materials give or bend in their breakup frequency, and they generally do in their operating frequency range, their resonances must be carefully apportioned and controlled – i.e. damped – to try to attain the highest sound quality. Resonances do color the sound, and their presence is often seen as irregularities in the loudspeaker’s frequency response. Paradoxically, how these errors appear in the measured response may not always be a good indication as to how they actually sound. Like playing Classical string quartets on a typical metal coned hi-fi loudspeaker doesn’t always make the reproduced sound of the Classical string quartet recording sound as if it is always accompanied by a xylophone or by Zildjian and Paiste cymbals.

With softer damped materials – like fibrous paper or pulp card, Bextrene and Polypropylene plastic and bonded matrix composites – bending may be imperfect because these materials don’t act as perfect springs to begin with. A true linear spring recovers immediately from deflection or deformation with near 100% restitution after being stressed. In contrast, many composites and plastics show some memory effect, a slower recovery after bending, and some nonlinear compression with higher forces. This may result in a change in sound quality as sound level is increased. The nonlinear response to high bending forces, and the slowed recovery after bending – technically speaking, it is a form of hysteresis –is a factor in the overall linearity of the driver. In return for the favorable internal damping from a resonance viewpoint, non-metal-cone technology can provide a smooth response, nicely extended to the required upper limit, and then may often deliver a smooth acoustic rolloff beyond this point.

In contrast, the metal diaphragm or cone may be essentially perfect from its bass resonance to beyond the required range, and have no resonance whatever in its lower operating region. Potentially, it has a singular freedom from compression and hysteresis distortion. Subjectively, that manifests itself, if the overall system design is of sufficient quality and a great tonal neutrality, a sound with expressive dynamics and a high dynamic range. Clarity can be very high and low-level detail excellently resolved, in short, fine transparency is a typical of the genre.

However, there’s a price to pay. Like for like, metal cones are generally heavier than the alternative cone materials and magnet for magnet, this often results in reduced sensitivity, often a loss of 2 to 3 decibels. Metal cones are substantially more expensive than paper pulp or plastic equivalents – not to mention the seldom stated fact that metal cones destined for metal coned loudspeakers have a higher reject rate in their production in comparison to paper and plastic.

Finally, while there are no resonances in their primary frequency range, when a metal cone does finally give up and resonate, it lets go with a greater exuberance than a paper or plastic coned driver. So severe is the first resonance that it can rise 10 to 15 decibels above the main response and with sufficient energy to suck power out of the adjoining frequency bands. Thus, a 6.5-inch metal coned driver might resonate at 6-KHz – desirably higher than the 1-KHz typical resonance of a good paper or plastic coned driver – but it does so with such amplitude that the cone output decays prematurely into a pre-resonant suckout, tailing of above 2-KHz. This makes the crossover design of a metal coned hi-fi loudspeaker much more awkward.

This means that if the crossover rolloff isn’t sufficiently fast – i.e. not enough high ordered crossover slope – some of that 6-KHz peak may pop up into the treble band, roughening both the tweeter’s sound and its measured response. Some hi-fi loudspeaker designers resort to anti-resonant traps: electrical filters that seek to notch out the resonance and remove it from the system’s sound. This may seem like a brilliant engineering solution, but it limits the loudspeakers’ compatibility with power amplifiers – i.e. single-ended triode amplifiers with a low damping factor doesn’t like these kind of speakers.

Ultimately, it is up to the loudspeaker designer to make the best choices in the overall system build, regardless of the cone technology employed. Excellent sounding high fidelity loudspeaker systems have been produced over the years that use every conceivable combination of driver technology. Just hope that if you finally found your ideal hi-fi loudspeaker, sound quality wise, it is within your range of affordability.

Plastic Coned Hi-Fi Loudspeakers: Brilliant Engineering Solution?

2011-11-02T03:33:00.000-07:00

First touted supposedly as an ideal solution against cone break-up inherent in early paper coned hi-fi loudspeakers, do plastic coned loudspeakers offer a brilliant engineering solution?

By: Ringo Bones

Maybe is it because on my first-hand audition of supposedly high-tech Bextrene and Polypropylene (MRP – Mineral-Reinforced Polypropylene) high fidelity loudspeaker cones whose drive units are well enough engineered to give smooth string tone, but on orchestral crescendos suffer from timbral muddle and tonal quack; I mean an overwhelming majority of them – i.e. ones within my price range – display a degree of plastic quack that was apparent with violins, plus a little nasality, just enough to add character when played at sound-levels of a typical violin or a Classically trained singer performing live sans electronic amplification. Fundamentally, the argument in favor of plastic cones over paper cones rests on plastic’s high stiffness in comparison to paper, with the potential avoidance of any unwanted resonance or cone “breakup” in the intended working frequency range. But were plastic coned hi-fi loudspeakers really has more flaws in comparison to the paper coned loudspeakers they are intended to replace?

Use of heavy, well-damped plastic cones that display a great measured performance – frequency response flatness wise – but little else in terms of subjective purity of tone and timbre (i.e. sound quality) came about as a result of a research into loudspeaker cone materials started by the BBC that culminated in the early 1970s. Thus prompting established high fidelity loudspeaker manufacturers of the time to switch from paper cones to plastic cones – i.e. Bextrene and Polypropylene. When other established hi-fi loudspeaker companies with bigger R&D budgets like B&W, KEF, Celestion and Wharfedale equipped themselves with sophisticated research facilities during the early 1970s eventually merely confirmed what the BBC had discovered a few months before, thus taking to plastic cones with enthusiasm. But to the ears – and wallets – of long-time hi-fi enthusiasts, too many top line monitors with plastic coned drivers brewed up in Britain between the early 1970s up to the early 1990s have sounded perplexingly poor in relation to their enormous engineering input for questions not to have been asked.

Fueling me and other hi-fi enthusiasts growing suspicion on the capabilities of plastic coned loudspeakers was back in 1995, when the well-established loudspeaker company called Mission produced the 731 LE whose better performance was largely due to switching from the use of plastic to a doped paper cone on the main driver. Even though there are scores of loudspeaker manufacturers – mainly in Britain – who swear by performance of plastic coned drivers – i.e. Spendor, Rogers, KEF, etc. But more often than not, plastic coned loudspeakers are still viewed by an overwhelming number of veteran hi-fi enthusiasts as something that’s good enough for mainstream pop and rock music, not for music that demands a little more precision and soulful rendition.

Paper Coned Hi-Fi Loudspeakers: The Best Hi-Fi Speakers?

2011-09-16T04:13:00.000-07:00

Despite their faults – and there’s a lot of them – do paper coned hi-fi loudspeakers truly deserve the title as the best of its kind?

By: Ringo Bones

Maybe its just because I’m a loud electric guitar music kind of guy or was it the glut of entry-level hi-fi loudspeakers during the 1990s that got “best-buy” status - -i.e. the doped paper-coned Mission 731 LE back in 1995 - when they were equipped with paper-coned loudspeakers that fueled the prejudice in me and thousands of others in our first-hand auditions that the paper-coned hi-fi loudspeakers are the best of its kind. To avoid being accused of being economical with the truth, paper-coned loudspeakers have their own share of nasties – i.e. cone break-up at high listening levels can result in a tonal coloration which can jar the senses. But given that other alternatives – i.e. mineral-filled polypropylene, high-definition Aerogel, Kevlar, carbon fiber, aluminum and magnesium metal cones and even diamond coated ones – are not entirely free from coloration and are somewhat pricey, does this mean that paper-coned loudspeakers have a unassailable cost advantage from an engineering standpoint too?

Influential personalities in the field of hi-fi equipment design and the contemporary music industry all have their share of praises for the paper-coned loudspeaker. Back in 1994, Ken Ishiwata – chief engineer of Marantz – tells the hi-fi press at large that the best way to treat paper cones for use in hi-fidelity loudspeakers is to soak it in oil for 48 hours to give it a gorgeous tone and dark inter-transient silences. But the process of manufacturing Ken Ishiwata’s oil-impregnated low tonal coloration paper-coned hi-fi loudspeaker is definitely not a technique that lends itself well to contemporary mass production.

In the loud electric guitar playing world, guitar god Yngwie Malmsteen has a now-famous “tone testament” on the paper-coned Celestion G12T-75 electric guitar speaker saying that it compliments the violin-like tone and feel of his guitar playing. Malmsteen also says that he has used Celestions ever since the early days of his guitar playing career in Sweden.

And famed High End hi-fi equipment manufacturer - Yamamura Churchill - uses a rare paper sourced from select hand-made bamboo pulp from Japan on the cones of their top of the line loudspeakers. The “reign” of the paper-coned hi-fi loudspeaker could ultimately blamed on the seemingly immortal runaway popularity of loud electric guitar music of hard rock and heavy metal music, don’t you agree?

It’s The Power Supply, Stupid!

2011-04-07T03:26:00.000-07:00

Mainstream audio engineers as usual may beg to differ, but how much does power supply design and topology affect audiophile grade audio amplifier sound quality?

By: Ringo Bones

Charles G. Whitener, Jr., president of Western Electric Audio Products wrote his views on this particular subject matter which got published in the December 1997 edition of Stereophile magazine which goes: “We have come to this really arrogant conclusion: When tubes are removed from the chassis, the amplifier becomes nothing more than an expensive power supply.” There may be some truth to what Whitener had said – whether vacuum tube based or solid-state designs, it has been experienced by seasoned audiophiles time and time again that that power supply design and topology does play a role in the empirical assessment of sound quality of a typical audio power amplifier marketed to audiophiles. But is there really something more going on here?

The topic of power supply design and topology and its effect on the subjective sound quality of a “well-engineered” audio power amplifier – like the design and topology of the analog output stage of a universal CD / DVD player – has always been and probably will always be a politically charged topic to “mainstream” audio engineers. The issue is often seen by mainstream audio engineers like a mandatory sexual harassment / gender sensitivity training aimed at their machismo driven chauvinist little corner of the universe. But given that audiophile grade audio amplifiers – unlike mobile phones – are aimed at hi-fi / audiophiles who listen to them with their own two ears instead of connecting them to a 22,000 US dollar Fast-Fourier Transform audio analyzer, should mainstream audio engineers pay more attention to the power supply design and topology of audio power amplifiers?

Ever since the latter-half of the 1980s, audio engineers who still care about the sound quality of their designs and final products have come to conclude that the overall impedance of the power supply is a much bigger problem than anyone has previously thought. Electrocompaniet’s Per Abrahamson in a January 1998 edition of Stereophile magazine interview says that the power supplies of 99% of the amplifiers on the market are designed with big capacitors, big transformers, big everything – without taking into account the frequency response of the power supply.

When the impedance of the power supply is all over the place, the problem manifests itself as a problematic unnatural sounding midrange and high-frequencies in the finished audio amplifier during audition. The impedance of the power supply is a mirror into the subjective frequency response – but you won’t find anything wrong with the audio power amplifier if you measure the frequency response by sinewave measurements. No problem even via a 22,000 US dollar FFT test gear. If you do tests by auditioning with well-recorded music and via your own two audiophile-seasoned ears, you can hear that the power supply design and topology does affect the frequency response. Audiophiles, musicians or anyone who gives a rat’s ass can hear it but we can’t measure it with fancy 22,000 US dollar FFT gear.

So if you are fortunate enough to have the opportunity to peek into those audio power amplifier designs famed for their sound quality, I just hope that the ultrafast Schottky rectifiers or those 15-nanosecond HEXFRED diode rectifiers, banks of electrolytic capacitors instead of a single dustbin-sized 100,000 microfarad capacitor won’t pose as an audio engineering culture-shock. All of these hi-fi tweaks serve to make a relatively modern sensibly-priced solid-state audio amplifier aimed at audiophiles to sound like their tube-based Golden Age of Stereo counterparts.

Of Music Lovers and Illegal Music Downloads

2011-02-28T01:33:00.000-08:00

Intellectual property legal precedents and economics aside, why do an overwhelming number of music lovers put up with the dubious quality of illegally downloaded music?

By: Ringo Bones

Once upon a time, we music lovers used to show our devotion to our favourite musician by making them obscenely rich. We even tried to be musicians ourselves in the hopes of becoming obscenely rich too without resorting to being a narco-trafficker or a despotic leader. Then came the dreaded Napster at the very tail-end of the 20th Century and thus financially ruining the whole music biz, musicians and wannabe musicians like me. Only musicians – ageing ones - with a back catalogue proviso on their record-label contracts manage to escape the Napster scourge. Intellectual property legal precedents and economic concerns (as in free music) aside, why do most of us music lovers – even me at some point – put up with the film-noir like rigmarole of illegal on-line digital music downloads?

From a hi-fi enthusiasts’ perspective, our hi-fi rigs – with front ends that range from a humble lathe 20th Century era portable MP3 player, i-Pod, snazzy vintage turntable and for the fortunate few a state of the art CD player that is as expensive as a South Korean made family sedan that can play your CDs sounding like vinyl LPs – is the primary tool that allows us to hear music as it was recorded. The better the hi-fi rig, the closer the approach or the sound quality to the master tape. Heck, even women’s fashion magazines Glamour and Cosmopolitan featured articles back in 1999 and 2000 about how Britney Spears and Christina Aguilera all used to record to big-ass open-reel analog master tapes in their way of spreading the concept of sound quality as a way swaying the hoi polloi away from Napster and their ilk. Sadly, it didn’t work.

Somewhat reminiscent of the adage of saving your hard-earned cash until you can afford to buy that particular tool that would do the job right, it is also the rationale of making the most of your investment in vinyl LPs, CDs and those hi-resolution digital formats like SACD and 24-bit 192-KHz sampled DVD-Audio. Play a full priced CD – at around 15 US dollars – on even a good Mainland Chinese manufactured boom-box and at the very most you’ll hear only 7 US dollars worth of fidelity. Spend a little more on a decent entry-level hi-fi separates – usually start at around 500 US dollars these days and is usually composed of either American or Japanese made universal CD/DVD player, an integrated amplifier and some speakers at around 150 US dollars each item and the rest on interconnects and speaker wire - and you’ll soon get 10 US dollars worth of fidelity.

Sadly, those supposedly “free” music downloads that are illegal from the music biz’s perspective is not exactly “free” from our perspective. I mean that is our very own money that we spent in buying our home computer set-ups – may it be portable lap-tops or desktop work stations. Our own money used to pay to the internet service provider or the hourly rates of your local internet café.

My most nasty encounter with those music download sites of dubious legality are not only virus/malware related, it can also prove to be a waste of time. Given that our friendly neighbourhood music store has never been “adventurous” enough to stock expensive rare and audiophile-quality CDs that range in price from 25 to 50 US dollars even though quite a number of locals can easily afford it. I asked a net savvy friend back in 2002 for a site offering the Queensrÿche remake of Simon and Garfunkel’s Scarborough Fair that’s only available on a 50 US dollar Japanese CD pressing of Queensrÿche’s Empire album. All I got downloaded to my first-generation portable MP3 player was 4 minutes 30 seconds worth of digital silence. Talk about a waste of time.

Mainland Chinese Rare Earth Monopoly: Bad for the Hi-Fi Industry?

2010-11-30T00:40:00.000-08:00

Even though Beijing had resumed rare earth metal export to Japan, does the Mainland Chinese monopoly on rare earth metals bad for the hi-fi industry in the long run?

By: Ringo Bones

When it comes to the use of rare earth based ultra powerful permanent magnets, the hi-fi industry is probably without equal. From the relatively large samarium cobalt and neodymium boron iron magnets used in dynamic loudspeakers to the tiny magnets used in tape-based analog tape record / playback heads known for their glorious non-fatiguing warm analog sound. Not to mention the CD / DVD player and LP turntable motors that contain rare earth magnets, come to think of it, the hi-fi industry is probably the most rare earth dependent consumer electronic industry on the face of the planet.

Even though Mainland China’s quotas of rare earth metals being exported into the global market has more or less returned to the pre-conflict with Japan levels back November 24, 2010, Mainland China’s virtual monopoly of the global rare earth metal industry is not only detrimental to the world’s high-tech industry that’s very much dependent on rare earth metals but also its concept of “quality” – especially when it comes to hi-fidelity audio – is wholly different that of the Japanese obsession with Single Ended Triode amplifiers or of the Western concept of absolute sound quality in general. I mean had Mainland China ever produced its own version of a cost-no-object CD player set to rival the sound quality of a 7,000-euro German made Burmester CD player?

With Mainland China’s proposed 120 nuclear reactors it plans to operate to lower the country’s carbon footprint, rare earth metal export quotas might further be reduced. After all, they would probably be using their mined dysprosium and holmium as burnable poisons for their fission-type nuclear power plants. Not to mention the use of other rare earth metals for the magnetic relays, making the hi-fi industry yet again raise prices due to rare earth metal scarcity and pass on the expense to us hi-fi enthusiasts / capitalist consumers.

Add to the recent Wikileaks revelation that the Beijing government wants a North and South Korean reunification with the Seoul government in charge wold pose a rather significant geopolitical risk in the security of Mainland China's ability to maintain the commercial trading of rare earth metals. It would be sooner rather than later that Mainland China’s virtual monopoly on the rare earth metal industry won’t allow it anymore to keep up with global rare earth metal demand since all the rare earth metals it produces will only be enough for domestic consumption.

Can Recorded Grunge Guitars Destroy Your Tweeters?

2010-09-16T08:04:00.000-07:00

Once often asked during the rise of Seattle Grunge movement, do playing recorded “grunge” guitars on your hi-fi kit eventually destroy your tweeters?

By: Ringo Bones

Part of the rationale of owning a really good hi-fi rig is the ability to play loud without hurting your ears with aggro of distortion. Surprisingly, I’ve just recently found out as recently as a couple of weeks ago that there are still really – I mean really – naïve audiophiles who genuinely believe that playing recordings of “grunge guitars” – i.e. highly distorted and very loud electric guitar passages can eventually result in tweeter damage of your loudspeaker. I don’t know if these naïve audiophiles ever actually heard one played live or been in a Nirvana or a Soundgarden concert, so it is yet premature to judge. But the “assumption” that such “hot guitar tone” can fry tweeters is partly based on misinformation over amplifier clipping.

Every audiophile and hi-fi rig owner knows that pushing a power amplifier into hard clipping – i.e. playing it too loud that it no longer sounds nice – will “fry” or burn out your loudspeakers’ tweeter coil because the clipped waveforms contain much more high-frequency energy than a typical music signal. Given this truism in the physics behind the workings of electronic amplifiers, one will thus be curious enough to ask: “What happens when the music itself naturally contains heavily distorted clipped sounds – like those in loudly played and distorted electric guitars played through a fuzz pedal set on high or even extremely high? Will this result in tweeter damage too?

The truth – fortunately to us rockers – is that distortion produced by electric guitars played through “fuzz” or distortion pedals being set to extreme grunge is not nearly as destructive in comparison to actual amplifier clipping. Sound quality wise, I really don’t believe that the distortion tone created by guitarists and their special equipment is nearly as rich in harmonics as the distortion produced when a power amplifier truly clips.

The upper frequency of the harmonics produced by an overdriven guitar amp is limited by the instrument amp – which is more likely vacuum tube equipped with an output transformer coupled into a single-coned electric guitar loudspeaker – and the medium in which the instrument is recorded on – i.e. analog magnetic tape running at 30 inches per second. Ultimately restricting the bandwidth of a loudly played distorted electric guitar to lows of about 75-Hz to highs of about 5,000-Hz.

Just listening to such Seattle Grunge music makes me feel that much of the distortion behind its distinctive tone occurs at midrange frequencies where our ears are most sensitive to, rising into the treble range but decreasing in amplitude as the frequencies of the harmonics rise. A typical “clean” jazz guitar track played on a vacuum tube-equipped combo guitar amp typically measures 200 to 300 % total harmonic distortion. The electric guitars in a typical Seattle Grunge rock’s total harmonic distortion figure probably lies closer to 1,000% THD or even more.

Furthermore, if tweeters were actually being destroyed during playback of such music, older audiophiles would have read about it in 1990s era hi-fi magazines. And might even necessitate labelling such cassettes and CDs back then with warnings of potential tweeter damage when played loud in addition to the PMRC Parental Advisory, Explicit Lyrics warning stickers. Fortunately for music lovers of the world, no tweeters had even been martyred alongside Kurt Cobain during the heyday of Seattle Grunge.

Audiophilia Nervosa: Ear Pornography’s Inevitable Consequence?

2010-09-16T07:31:00.001-07:00

The “audiophile disease” that first gained widespread notice during the mid 1990s, is audiophilia nervosa the inevitable consequence of compulsive hi-fi tweaking?

By: Ringo Bones

This insidious “audiophile disease” can easily infect an unwary audiophile noticing how a DIY RG-58 cable being used as an ad-hoc interconnect managed to sound way much better – sound quality wise - than the “scrawny” freebie interconnect that came with the newly-purchased CD / DVD player. And before you know it – especially if you’re not careful – audiophilia nervosa is often that not far behind, but should it be?

From my perspective, it usually afflicts audiophiles with a fairly narrow musical taste – genre wise. Or those intentionally unwilling to explore other genres of music are highly susceptible. Depending upon one’s perspective, a music reproduction system – namely the hi-fi rig that you own – should not influence which music you play on it. But more often than not, many hi-fi systems do.

Now is the time to ask yourself, does your hi-fi system make you exited about the music you play – or the way it sounds? If it is the latter, it’s no doubt you have now an advanced case of audiophilia nervosa and should take steps – really careful steps – to avoid forgetting your record collection. In a perfect world, your hi-fi rig should steer you – the listener – away from itself by letting the style and content of music carry you away. But more often than not, one is more likely distracted by overkill bass and supermarket tabloid style attention-grabbing treble. Well, at least my current hi-fi rig can play a well recorded rock drum kit way better than the hi-fi currently being stocked at our local mall. Or was it making the recorded singers sound like their right in front of me?

Digital Loudspeakers: Viable Hi-Fi Technology?

2010-08-22T07:54:00.000-07:00

Given that almost all aspects of domestic hi-fi front-end has already gone digital these days – digital radio broadcasts, CDs, DVDs, digital music downloads, etc. Are our hi-fi loudspeakers the next component to go digital?

By: Ringo Bones

Virtually all aspects of hi-fi that’s still commercially viably traded has already gone digital, thanks to the slogan Going Digital and Digital Ready being brandished about for much of the 1990s. As in digital radio broadcasts, digital music downloads, CDs, DVDs, digital preamplifiers, digital power amplifiers, etc. Even analog TV broadcasts in the US has since virtually gone digital back in the middle of 2009. But has anyone recently checked if the humble hi-fi workhorse, namely the ubiquitous hi-fi loudspeaker, has already gone digital?

Back in September 1998, a start-up digital speaker development company called “1…Limited” has then announced a new drive to attract investors and partners (I smell IPO?). The Cambridge-based company at the time aimed to make its innovative technology out of the laboratory and into production – and hopefully into your listening room – within two years. The design concept of 1…Limited was a panel matrix loudspeaker which runs from raw digital code (SPDIF?) without the need for any Digital to Analog Converter (DAC) or power amplifier. Given that our ears – as far as we know at present – are analog and, therefore, a digital speaker must create sound waves in the air by integrating air pressure pulses – from an amplified bitstream from either CD or DVD player into the listening room.

During the past 30 years or so, all major consumer electronic manufacturing firms – Philips, Sony, Panasonic, etc. – have been working on digital speakers, more often than not filing their very own patents to the nearest patent office of their very own versions of the same theme – i.e. digital loudspeakers. And all of them eventually found out first-hand the nasty surprise that’s in store.

Full working details of a digital loudspeaker were already published back in April 1980 – three years before CD was commercially launched by Sony and Philips. The article appeared in the now defunct magazine called Hi-Fi For Pleasure. The author was Stan Curtis – who eventually invented the audiophile CD player in 1985, later became MD of Wharfedale loudspeakers and Chairman of IAG, which owns the hi-fi company Quad. Stan Curtis’ article was spread over two pages and included a block circuit diagram and sketches said to be taken from a patent application filed by a Japanese company.

The system was called DARTS, or Digital Action Reaction Transmission Speaker, and it has been developed by NEBCO, the Osaka-based Nippon Electrical Bearing Company. Before reporting on the demonstration to selected journalists, Curtis reminded everyone that the loudspeaker has been the major stumbling-block to any progress in the digital chain – i.e. a truly all-digital hi-fi system.

NEBCO set up a demonstration using specially produced digital discs replayed on a prototype Sony disc player. According to Stan Curtis, the subjective performance defies description. There was no noise, no distortion, no coloration, wow and flutter or rumble, and apparently unlimited reserves of volume. The result could not be compared to anything heard previously: it was just so real. One particular revealing passage was an atmospheric-sounding street recording. Being reproduced at sensible level, the effect was as though someone had opened a window out on to the street.

NEBCO’s sketches showed a flat panel built from a helix of numerous tiny pistons, selectively triggered by a digital bitstream. For low-level sound, only the central drivers were switched on, to pump a few packet pulses of air. As the pitch and volume or a note rose, more drivers were rapidly triggered. At maximum sound level, all the drivers pumped. The discrete packets of air integrated in the room to create an analogue soundwave. Because each driver was either on or off, there could be no distortion or coloration like that found in a conventional analog speaker.

NEBCO promised a 450-quid bookshelf version, but it never appeared. Those in the know where not surprised because Stan Curtis wrote the article under the pseudonym Olaf Pirol – an anagram of April Fool. For all intents and purposes, DARTS was an elaborate hoax to celebrate the first of April 1980 a.k.a.April Fools Day. When 1998 rolled in, only a few hi-fi industry insiders knew the truth. But Stan Curtis eventually owned up to the elaborate hoax that he created through a trade magazine called Inside Hi-Fi in 1998. A few years later, he still finds hi-fi designers who wonder whatever happened to DARTS.

Unfortunately, most existing patent laws around the world makes no distinction between fact and fiction, a mere blueprint from an actual functioning and working prototype. In short, you can definitely patent a blueprint even if the device portrayed by it doesn’t work in real life. Although Olaf Pirol’s digital speaker article was fiction, it will still block anyone who now tries to patent a similar idea as fact – even if he or she possesses a working prototype.

Ear Pornography: Do Audiophiles Know it When They Hear It?

2010-08-10T18:45:00.000-07:00

May have started as a Quixotic quest to make our hi-fi rig sound like live music, but does tweaking our hi-fi rigs to make them sound better than the real thing nothing more than ear pornography?

By: Ringo Bones

The concept may have started when some audiophiles and hi-fi enthusiasts who can’t take some of the dark and brooding aspects of Vladimir Horowitz’s piano playing resorted to tweaking to make the famed piano player sound like the bright and breezy Liberace. From then on, audiophiles have used judicious choice of analog and digital interconnects and speaker cables and tube / valve substitution and Rubycon Black Gate capacitors – with varying success – to make their favorite artists sound like the way their respective egos intend them to sound on their hi-fi rig. But is it still keeping up with the spirit of owning a hi-fi in the first place – that is the life-like reproduction of music in the home? I mean is the concept of ear pornography nothing more than the really Quixotic quest to make your hi-fi’s sound reproduction abilities better than the real thing / real life?

The hi-fi inconvenient truth is that we don’t actually listen with our ears, we actually listen with our minds and our emotions (or egos?). In short, how much we hear depends very much on how much we want to hear. Subconsciously, our mind can block out everything but the music or scrutinize the most subtle nuances of the musician’s rendition of a certain piece of music or the recording engineer’s production techniques. Every hi-fi enthusiast has a preference somewhere between these two extremes of auditory scrutiny.

To the uninitiated, the clean and clinical sound of contemporary digital-based hi-fi can be a pain in the ear to anyone weaned on the mellow and mellifluous sound of yesteryear. Choosing the right interconnect cables to make the audiophile recordings - if they have one - of your favorite artist. Like Taylor Swift, Nina Gordon and Louise Post of Veruca Salt, Anneke van Giersbergen of the Gathering or Liz Phair sound like a Central Asian Bardic Diva may seem like mere ear pornography to the unsympathetic audiophile. Strange, given that people who are generally offended by conventional pornography are more often than not suffers from poor body image. Does this mean that people who are offended by ear pornography are either tone deaf or is not blessed with a decent singing ability? Still, there’s a good chance that worthy audiophiles will probably know ear pornography when they hear it.

Can Tweaking Your AC Cables Actually Make a Difference?

2010-06-10T19:13:00.000-07:00

Electrical engineering-based logic dictates that doing such tweaks shouldn’t make a difference, but does tweaking your AC cables by using higher quality cables improve your hi-fi system’s sound?

By: Ringo Bones

As with the crappy quality freebie analog interconnect cables that most seasoned hi-fi buyers are already familiar with, an overwhelming majority - if not all – freebie IEC AC cords that come free with newly-purchased hi-fi equipment is stifling their ability to display their full sound quality potential. More apparently so when entry-level audiophile AC cords are substituted to the free AC cords that came with your CD player or other hi-fi audio equipment. Inexplicably, major electronics manufacturers seem to be unable to move away from supplying crappy analog interconnect cables and IEC AC power cords with their products.

From an electrical engineering perspective, one can logically deduce that tweaking the last ten feet of your AC mains cables by using higher-spec copper wiring configured in proprietary geometric configuration that results in RFI and EMI noise cancellation shouldn’t make a difference, doesn’t it? I mean the AC power that traveled from the generating plant all the way to your home is not exactly made with copper of 99.9999% - i.e. of six-nines purity. Neither are they ceramic-coated with superconducting “space age” materials nor have Teflon dielectric, and chances are doesn’t have conductors arranged around some mystical geometric pattern. Existing electrical codes around the world specify that 99.9% copper is good enough. Then why does using fully tricked-out AC cables – even those IEC AC equipment entry-level ones priced at around 20 to 25 US dollars – during the last 10 feet of mains to your CD / DVD player and power amp make such a noticeable improvement in sound quality?

I’ve heard the theories before – most are dismissed by “mainstream” / “tenured” electrical and electronic engineers as mere voodoo, but more importantly, I’ve heard the difference. As in greater dynamic range as if the music being played seems to immerse from a blacker background then shining brighter than it did after the generic AC cords had been substituted with better ones. My converted audio-buddies who were mere civilian bystanders – in audiophile terms - when I first asked them to be listening guinea pigs back in the late 1990s had since swore that AC cable tweaking makes a more-than-noticeable difference. Even with a beer-budget version of the test that I have conducted when I replaced the AC mains cabling of my out-of-warranty power amplifiers with well-reviewed entry-level speaker cables.

Yes, even speaker cables of suitable thickness to handle the power demands of the integrated amplifier or power amplifier you intend to use them with had shown a marked improvement in sound quality. After asking a qualified electrician in our neighborhood if what I’m doing violates any existing electrical codes. He says – it is still usually a he even till this day – given that those speaker cables are rated up to 600 Volts AC or DC, it is quite ok to use them as mains cable. He says they may even be safer than existing “zip-cords” oft used as AC mains cabling since these speaker wires contain more copper – i.e. thicker diameter. They are only a few percentage points purer than the copper used in freebie AC cords – 99.9% of ordinary zip-cords versus 99.999% of the hi-fi speaker wire. Can that much purer copper result in an inexplicable increase in sound quality?

If you’re lucky enough to have an integrated amplifier or a power amplifier that still works / you are still using that has already past its warranty and you are confident of your DIY soldering skills. You can try replacing the captive AC cords of your preamplifier, power amp or even the CD / DVD or other front-end with entry-level speaker wire like those from Bandridge, Gale, or Cable Talk that are priced between 1 to 5 US dollars per meter to improve its sound quality. This tweaks works very well with entry-level solid-state integrated amps with old-style captive AC cords, making them sound much closer to budget tube amps made during the Golden Age of Stereo or those 3,000 US dollar French-made solid-state integrated amplifiers.

Another source of cheap AC mains cords that are way better than the freebies that came with your CD / DVD player or integrated amp’s Styrofoam packaging are those IEC AC cords designed to protect against Van Eck radiation phreaking. Remember Wim van Eck, that Dutch computer researcher who in 1985 published the on how electronic emissions from a computer can be eavesdropped? Well, a friend of mine from the US State Department gave me – as in for free - 30 sets of IEC AC cords that formerly used in their computers that are capable of Van Eck Radiation filtering back in 1998 after their office computer workstations were issued “improved” models. Those 30 sets of 1992 Van Eck Radiation-compliant IEC AC cords also improves sound quality of my equipment that takes IEC AC cords. About as good sound quality wise as models priced between 500 to 1,500 US dollars from Electra Glide, Yamamura and even Cardas.

That Crappy Freebie Analog Interconnect Syndrome

2010-06-10T19:03:00.000-07:00

To the casual and first-time buyer it usually came with the Styrofoam that comes free with your CD player, but are those crappy freebie interconnects unduly ruining real hi-fi’s reputation?

By: Ringo Bones

Its only saving grace is that the plastic RCA plugs – or phono plugs as they are referred to in merry old England - are already gaudily color coded to whether it goes to the left or right channel RCA jack. But are these cheap freebie interconnects that comes with your CD player’s / cassette tape deck’s / turntable’s / tuner’s packing Styrofoam really have bad sound quality?

Flatteringly, they can make your real hi-fi CD player – or any other hi-fi front-end previously mentioned – sound just like a run-off-the-mill mini system boombox. Or in short, these freebie cables’ inherent crappiness can ruin the inherently excellent sound quality – in comparison to a run-of-the-mill mini boombox - of your “proper hi-fi” or “real hi-fi” CD player or any other “proper hi-fi” or “real hi-fi” front end. This phenomenon is probably the reason why some anti-hi-fi and anti-tweaking fanatics swear by to that all equipment sounds the same mantra.

During the latter half of the 1990s, I was fortunate enough to have the opportunity to employ a few of our local music fans as hi-fi “guinea pigs. Given that their only experience to high quality sound is the weekend recital of a pop music academy in our local mall and most – if not all - of their CD listening is via run-of-the-mill boomboxes could make them about the most unbiased hi-fi auditioning test subjects that anyone could find.

Using Veruca Salt’s Eight Arms to Hold You CD – which was newly released at the time – as an ad hoc “audiophile demonstration disc” all of them commented: “Yeah, it truly sounds that there are two girls singing just like in the Volcano Girls music video”. And “Those cables make the interplay between the Gibson Les Paul and Marshall Amplifier stacks and the drums sound as if it is happening real life.” Maybe the young lady meant “live”, but the most surprising thing to me is that they thought that CD could never sound this good. Comparing “proper hi-fi” interconnect cables – even entry-level price range ones with those crappy freebie interconnects that come free with the packing Styrofoam can be a “Road to Damascus”-like experience.

Despite of their excellent sound quality in comparison to crappy freebie interconnects, entry-level hi-fi interconnects are not exactly cheap. Ranging in price from 25 US dollars to 100 US dollars – they are easily more expensive that those ultra cheap Chinese Mainland made DVD players. You know ones that had been raved for their surprisingly good sound quality as a “30-dollar Wadia CD transport” and a “30-dollar Krell CD transport” (more on this in the future). Fortunately, me and my seasoned audio-buddies had found away to make “interim” hi-fi interconnects that are still way better sounding than those crappy freebie interconnects.

If you are handy with a soldering iron, you can easily make your own ad hoc audiophile interconnects by using 1 or 2-meter sections of RG-58 or RG-59 cables and soldering them to reasonably-priced RCA plugs – or phono plugs for those living in the UK. If you know the right people, you can even get used RG-58 and RG-59 cables at 5-meter sections for free, while entry-level gold-plated RCA plugs – reliable ones - hover around 1.50 US dollars each. With a capacitance rating hovering around 28 to 32 picofarads (or pF) per foot, they can even be experimented as an ad hoc digital interconnects which I’ll discuss in a latter topic.

Sound quality wise, RG-58 and RG-59-based DIY analog interconnects have a more natural portrayal of the Gibson Les Paul and Marshall Amplifier sound as played in the opening of that Veruca Salt song titled Loneliness is Worse when compared to those crappy freebie analog interconnects. I have an audio-buddy who is “very careful with money” is still using the RG-58-based DIY analog interconnect cables I made for him back in 1998.

But why do reputable hi-fi CD / front-end equipment manufacturers still provide crappy freebie analog interconnects? God only knows, but this syndrome is not just confined to the entry-level price strata (the very competitive100 to 500 US dollar price range) of CD players. One of my audio-buddy fortunate enough to afford Sony’s 3,000 US dollar CDP-XA7ES CD player back in 1995 was somewhat astonished to find out that this 3,000 US dollar CD player too was afflicted with the crappy freebie analog interconnect syndrome.

Though his prized possession still runs till this day although he was a bit peeved when the rest of his audio-buddies has stumbled upon the phenomena of the 30-dollar Wadia CD transport / 30-dollar Krell CD transport last year – i.e. 2009. More so when it made our trusty-but-rusty 500-dollar Audio Alchemy DAC circa 1995 sound “superficially” way better than his 3,000-dollar Sony CD player bought in 1995.

Motional Feedback: The Future of Loudspeaker Design?

2010-06-10T18:50:00.000-07:00

Best known as the working principle behind Velodyne’s patented High-Gain Servo System-equipped subwoofers, is motional feedback truly the future when it comes to hi-fi dynamic loudspeaker design?

By: Ringo Bones

Seasoned audiophiles, more often than not, had their first hand encounters with motional feedback technology via adverts – and hopefully purchases – of Velodyne’s world-famous servo-controlled subwoofers. These famed subwoofers are famed for their very low levels of harmonic distortion and coloration – when compared to their competitors’ offerings – that doesn’t use Velodyne-style High-Gain Servo System technology. But before we proceed any further, here’s a primer on what is motional feedback.

Motional feedback uses a second voice coil on the drive unit – typically a large woofer in stand-alone subwoofer systems – that provides a signal in which a tiny millionths of a second later is fed back into the amplifier, correcting distortion. The result – if correctly implemented – is amazingly powerful articulate bass / low frequencies devoid of coloration and distortion.

In those famous Velodyne subwoofer adverts of the 1990s, the company points to their use of a low mass – 2.5-gram accelerometer – that form the brains of their High-Gain Servo System. Velodyne mounts this amazing device directly on the voice coils of their subwoofer drivers, and measures the actual movement of the driver. The information is then sent back to a circuit, which makes corrections for any deviations from the pure output signal 3,500 times a second. Resulting in a virtually distortion-free bass even when the subwoofer is set at its highest frequency setting of 120-Hz.

My encounter with Velodyne’s FSR-18 subwoofer – one of the very best subs that we (me and my audio-buddies) can still afford when we still have Clinton administration era prosperity money during the 1990s. It can easily be described as a technological tour-de-force, imagine very loud and very clear bass subtle enough to portray the acoustic structure of the venue where the music being reproduced was originally recorded. Although early samples of the Velodyne FSR-18 subs were notorious for having loose wiring that came loose and slapped against the moving cone producing a tapping sound – evident when What’s Left by Lunachicks – from their Pretty Ugly album - was played during that particular listening session. Thus resulting in another flight to Hong Kong to our very friendly hi-fi dealer that gladly replaced our faulty subs.

In reality, motional feedback-type loudspeakers are a pain to design and make to work properly – tweaking one should only be a job for very gifted electrical / electronic / mechanical engineers – i.e. probably those skilled enough to make a humanoid robot that can run a hundred-meter dash in less than 10 seconds. It is not just Velodyne who had faced such problems developing and perfecting their very own motional feedback-equipped loudspeakers. Celestion and once-upon-a-time-loudspeaker-manufacturer Philips also experienced first-hand challenges one will likely encounter when flirting with motional feedback technology.

Graham Bank of Celestion once stated in a hi-fi magazine interview that a lack of positional reference in their prototype motional feedback loudspeaker design resulted in an enormous crack from the cone as it attempted to leave the chassis on musical peaks. Each time it did this, the connecting braids carrying the signal from frame to the voice coil broke, even though they were long enough to cope with the movement. Both Graham Bank at Celestion and Paul Mills at Tannoy have worked on motional feedback-type hi-fi loudspeakers during much of the 1970s and were somewhat convinced that that there were some deep seated difficulties in its application.

Even a notable demonstration of motional feedback technology by Philips – back when they were still making hi-fi loudspeakers – at their headquarters in Eindhoven, Holland, that motional feedback gave the sort of fast, tight and even bass most hi-fi enthusiasts dream about. Fantastic bass quality - provided that the user kept the volume down, otherwise, the driver instantly destroyed itself. The technicians at Philips also noted in their motional feedback loudspeaker experiments conducted during the 1970s is that much of the correction by the accelerometer and the servo system was being applied to signals above 100-Hz.

So is motional feedback the future of high-end hi-fi loudspeaker design? Well, remember how Velodyne’s FSR-18 subwoofer compares the deviation from the pure output signals and the one sensed by its low-mass accelerometer at 3,500 times per second? This is just with an audio bandwidth that rolls-off at 120-Hz – although it works beautifully, imagine this concept applied to the full Redbook spec CD audio bandwidth of 20,000-Hz. Corrections would be applied at 600,000 times a second – that’s just with a 20,000-Hz bandwidth. Imagine the difficulty with DVD-audio or Super Audio CD / SACD that reaches out to 100,000-Hz – a motional feedback hi-fi loudspeaker with a 100-KHz bandwidth would be doing servo corrections at 30-million times per second. Full audio bandwidth motional feedback hi-fi loudspeakers may be the future if its quirks are ironed out, but for now – and for simplicity’s sake – they’re only practical for subwoofers that only play notes as high as 120-Hz.

It Came From Outer Space?

2010-05-30T18:28:00.000-07:00

Believe it or not, the Dolby noise-reduction system in the lowly cassette tape had their origins in radio astronomy work, where no hi-fi has gone before?

By: Ringo Bones

Most knowledgeable audiophiles – and probably even most radio astronomers – don’t know that Ray Dolby, of audio tape noise-reduction fame, did his early work in radio astronomy. This little noted and remembered factoid served as the basis for his inspiration in developing the Dolby-B type noise-reduction system. The very system that lifted the lowly cassette tape – developed by Philips as a lowly dictation recording medium – into the realm of convenient high fidelity audio home recording medium, thus earning Ray Dolby enormous wealth.

Ray Dolby’s early work in radio astronomy made him develop his electronic skills in developing ways to extract very weak cosmic signals from background radiation noise – and the increasingly “loud” Earth-based radio broadcast chatter. By the end of the Cold War, many radio astronomy communities had asked Dolby Labs – as a philanthropic gesture – to honor its founder’s origins and further Ray Dolby’s earlier work by applying some of their know-how toward reducing RF noise here on Earth. Particularly at frequencies of interest to radio astronomers.

By the end of 2009, something strange happened. Frank Drake – father of the Drake Equation often used to compute for the probability of intelligent life elsewhere in the Universe other than our own – had surmised that given the current trend to fiber-optic bound Internet telecommunications, our planet will soon be invisible to radio telescopes elsewhere in the Universe. Looks like those old Star Trek original series broadcast will soon be the last RF signals that we’ll be “accidentally” sending to space once Internet TV comes on line and gains worldwide acceptance. Looks like Ray Dolby’s noise-reduction system and analog TV signals streaming out into interstellar space will inevitably be consigned to the dustbin of history.

Surround Sound From Just Two Speakers?

2010-03-30T07:10:00.000-07:00

The concept gained popularity during the 1990s as three-dimensional stereo or surround sound from two loudspeakers, but is it possible to have surround sound with just your front left and right speakers?

By: Ringo Bones

Older audiophiles would probably credit the 1957 EMI release called the SDDI stereo demonstration LP with its traffic noises, trains and an orchestra as the first two-channel surround sound capable recording. Yes, it has only left and right channels, but this EMI test LP record can project a soundfield behind you without the aid of rear speakers. By the late 1960s, probably by creative accident, Jimi Hendrix made his guitar fly around and behind the listeners head – something two-channel stereo supposedly can’t do – via creative flanging in the song Bold as Love from the album Axis Bold as Love. Unfortunately, no audio engineer during this time has reliably able to do the same with natural / field recordings – i.e. the sound of a bee buzzing in front then behind your head as it sounds in real life – using standard two-channel stereo.

Hence the hi-fi and record industry in the very tail end of the 1960s decided that since the multitudes already have stereo, maybe we’d introduce them to surround sound. And when 1970 came, everyone witnessed the birth of quadraphonic sound – it was called as such because educated people knew Latin in those days. Unfortunately, a format war resulted with many manufacturers introducing their own version of quadraphonic sound / four-channel surround-sound that the buying public became confused – and bought none. A surround-sound system based on a quad system patented by Peter Scheiber – i.e. Dolby Pro-Logic – which is very compatible to existing standard two-channel stereo was introduced too late, thus quadraphonic sound expired with barely a whimper in 1975.

Even though Dolby Pro-Logic eventually became the standard surround-sound format for home theatres of the 1980s, the prospect of getting surround-sound from just two front speakers is just too tempting a concept to ignore. A researcher from the Oxford Institute of Mathematics by the name of Michael Gerzon had been toying the idea at about the time when quadraphonic sound was on the wan that you don’t need four or more loudspeakers arranged around the listener for surround sound. Gerzon had uncovered during his research that it is possible to fool the brain into thinking that a sound lies behind you with just two front-placed speakers. That’s a lot of money and unnecessary boxes saved, thus various companies influenced by the data gathered in Michael Gerson’s research had released their version of two-channel surround-sound that are - fortunately for us audiophiles - compatible with each other. Thus came Thorn EMI Sensaura, OM 3D system and Roland’s RSS system – all three dimensional stereo surround-sound systems that works with just two channels at the beginning of the 1990s.

At around near the end of 1993, the Thorn EMI Sensaura two-channel compatible surround-sound system was announced to the unsuspecting audio world as a surround-sound system that uses your existing standard two-channel stereo. Developed by EMI in their Central Research labs by Dr. Alastair Sibbald and team, Sensaura is an ingenious and complex recording trick that relies on a comprehensive understanding of psychoacoustics to work properly. It processes acoustic positional cues into a recording, in order for the ear / brain system to hear sounds from all around the room. And the end result can work whether recorded on CD, LP or cassette tape – and Sensaura’s effects can only get better the better the recording format sounds. And it even enhances high-resolution digital audio formats like 24-bit 192-Khz sampled DVD-Audio.

Another system with an almost similar principle that had been first made commercially available to the public since 1991 is Perfect Pitch Music’s OM 3D system. Used in their Francinstein Stereo Enhancement System Plus, the OM 3D system uses psychoacoustic cues to position individual sonic images within a 360 degree arc anywhere about the listening position. The OM 3Dsystem has been successfully used on CDs, cassette tapes, and radio broadcasts, it has even been used by musicians and recording engineers to enhance musical styles as diverse as experimental jazz and children’s educational tapes.

Like Sensaura and Roland’s RSS system, OM 3D uses left-right channel time delays to make low frequency sounds appear to come from beyond the boundary of the loudspeakers. In fact low-frequency stereo 3D stereo is relatively easy to create. It is at high frequencies that the 3D system / two-channel surround-sound systems previously mentioned has to be really clever. Because our ear / brain system determines acoustic directions at high frequencies by analyzing the tonal spectrum of a sound as it enters the auditory canal.

Unfortunately, as all of these three-dimensional stereo systems became popular, competing discrete digital surround sound systems – like Dolby digital AC3 and DTS – were introduced during the mid 1990s. Though an overwhelming application of the two competing discrete digital-based surround-sound systems were for movie soundtracks, a majority of audio-store “cowboys” had the brilliant idea of demo-ing The Eagles’ Hell Freezes Over DTS surround encoded DVD to death. Thus making your 1990s era home theatre customer inextricably linking DTS surround-sound with The Eagles’ Hell Freezes Over DVDs.

Since 1990, the audiophile label Chesky had been featuring three-dimensional stereo demo tracks in their test CDs. Though it doesn’t say on the CD liner notes, but many “mainstream” CD recordings that had came my way since 1991 had demonstrated surround-sound capability in my standard two-channel stereo set-up. Like the studio version of Dead Skin Mask by Slayer from their Seasons in the Abyss album when the hapless victim of Ed Gein had been calling him from behind my back even though my stereo only has two front speakers. There are now probably a large number of CDs out there that has already been three-dimensionally encoded that only became apparent if your main front speakers are properly toed in.

The Diorama Effect in Stereo Imaging and Soundstaging

2010-03-30T07:02:00.000-07:00

First observed as a visual artifact in 3-D cinematography, does the “diorama effect” also occurs in the world of audio?

By: Ringo Bones

Everyone might have very well underestimated the influence of James Cameron’s Avatar. Not only does it help sell a new generation of wide and flat 3-D capable video displays for the home, but also made everyone yet again notice what’s good and what needed improving about 3-D cinematography. Many 3-D cinematography enthusiasts point the blame at the “diorama effect” even though this visual artifact also occurs in prism-equipped binoculars, but does it have an audio equivalent that could give every hi-fi enthusiast a renewed bout with “audiophilia nervosa”?

Having been fortunate enough to acquire the funds to fully indulge myself in the experimenting and upgrading side of purist two-channel – i.e. stereo – audio during the past twenty-one years, a eureka moment finally dawned on me as I watched the 3-D version of Avatar. Especially the scenes of “near contemporary” military hardware and lush tropical fauna where every visual artifact that is incongruent with how our eyes see real life sticks out like a proverbial sore thumb. Which had me realize that two-channel stereo – like 3-D cinematography – has its very own version of the diorama effect that’s seldom discussed in the wider world of audiophile journalism.

Compared to how we hear an unamplified musical performance in nature, many purist two-channel stereo systems that I’ve encountered – especially those with transistor-based amplification – tend to produce a somewhat artificially structured soundstage. A soundstage that has a narrow listening area with imaging that locates recorded musical instruments and voices with a precision that never occurs in a natural unamplified musical performance. In short, an overwhelming number of two-channel stereo systems have the propensity to create an artificially detailed soundstage that sounds too good to pass muster as natural. The audio equivalent of the diorama effect?

Probably due to the way lithe budget integrated transistor amplifiers that became popular during the late 1980s tend to project acoustic images in a somewhat cubist manner, mainly due to the brightness their added switching distortion creates. Good sounding as these units are, audio enthusiasts who can afford experimented with tube based amplification – especially single-ended triode types – to minimize the cardboard cut-out like imaging producing the acoustic equivalent of the diorama effect of their audio system’s imaging and soundstaging capabilities.

Low power can be an issue, especially if you find the 300B single-ended triodes too dull and the even lower powered 2A3 has difficulty driving the speakers you currently have. But these designs are as good at individual precision images as any high-caliber transistor effort, though without that sharp-edge cut-out effect – i.e. the audio equivalent of that 3-D cinematography imaging artifact called the diorama effect. With good single-ended triode designs, you can as if walk around those individual sonic images. An audio refinement to make your stereo system’s imaging and soundstaging capabilities more akin to real life.

The Listener: The Often Ignored Hi-Fi Component?

2010-02-25T03:54:00.000-08:00

With a myriad number of tweaks already in under evaluation – and still growing, isn’t it strange that the most often ignored component in the hi-fi experiential chain is the listener?

By: Ringo Bones

Surely, this is yet another topic that won’t become a perennial bone of contention in the annual meeting of the Audio Engineering Society anytime soon. But do we – in the enthusiast’s side of the hi-fi community – find it just a bit strange that we, the listener, is the only major component in the hi-fi experiential listening chain that is not subjected to extensive tweaking. After all, our audio / stereo systems will not be listening to themselves anytime soon, right?

During the past few weeks, I’m beginning to wonder whether those “out-there” kind of tweaks – also referred to as advanced tweaks - are really nothing more than health and wellness tweaks, though not all of them, aimed specifically at us – the hi-fi listener / system owner. These “exotic” health and wellness tips are often referred to as alternative medicine by the Madison Avenue marketing men and they too are often dismissed by staunch objectivists as too “New Age”. Like those advanced tweaks that inextricably works to some degree in improving the sound quality of one’s audio gear. But what are they?

Drinking Polarized Water – a hi-fi tweak often attributed to Peter W. Belt. Polarized water in hi-fi tweak parlance is a drinkable water produced by placing a bottle or glass of water contained in a non-magnetic container to the north pole of a moderately-strong magnet - like loudspeaker and guitar pickup magnets - for 2 to 5 minutes. The listener drinks it in order to notice a marked improvement in sound quality of one’s audio gear. I think it works by relieving the stress of the listener. Allowing him or her to be musically more perceptive. As preliminary research by Professor Eshel Ben Jacob, a physicist from Tel Aviv University, have shown that stressfully purified water can make anyone who drinks it stressful. Maybe I’ll try drinking water purified by gamma radiation via cobalt-60, which is probably the most stressful water purification method that I know of – and has access to - in order to find out if this has a detrimental effect to the sound quality of my audio gear.

The Dreaded Pattern 5 Acupuncture Treatment – this is probably the most extensive and painful of all acupuncture treatments that’s offered to us – i.e. those of us without any lineage to mainland China’s great emperors whatsoever. But this particular acupuncture treatment has the greatest potential to restore the body’s energy and balance, although each one of the 47 or so needles that the acupuncturist had stuck into me felt like a 440-volt electric shock. The treatment did made me feel tired and sore, but after several minutes relaxing while listening to my audio rig, I’ve noticed that I’m hearing details that I never knew my systems lowly price tag had any right to produce.

A Vigorous Workout – it does work so well, especially after sever minutes when your body has assimilated all those endorphins produced during the exercise regimen. This not only makes you feel good, but it makes you feel as if you are listening to a much more expensive audio gear as you relax while listening to your favorite tunes. Better consult your doctor or GP first to find out if your body is up to it though.

A Several Days Fast From Your Audio Gear – this one is a perfect cure to those obsessive-compulsive tweakers. Try “vacationing” or “fasting” away from your audio gear for three days or more by hiking or fishing or doing any outdoor activity on your favorite spot as far from your audio gear as possible. You’ll be surprised how this one improves the sound of your audio gear and reduces your tendency to be an overly compulsive hi-fi tweak.

Of all these hi-fi / health and wellness tweaks that I tried, probably the most transcendent is the Pattern 5 Acupuncture treatment. It is transcendent in a way that it kind of makes you feel more contented of your possessions and the people around you. I wonder if the members of Grateful Dead have tried the Pattern 5 Acupuncture treatment? Anyway, all of them will not only improve the sound quality of your audio gear to some degree, but it also gives you – the listener – a much needed tweak to be better at all the other things that you do.

What Audiophiles Don’t Know About Polarized Water

2009-12-12T05:11:00.000-08:00

Even though the mechanism behind how it improves the sound quality of audio gear is still open to debate, is the audiophile world at large ignoring at their on peril by ignoring polarized water as an audio tweak?

By: Ringo Bones

As a really “out there” audio tweak often attributed to Peter W. Belt, the viability of polarized water as a viable way to improve the sound quality of your audio gear did manage to generate a significant cult following in the audiophile community. Even though serious discussion of the “science” behind how it works won’t be a perennial topic in the annual meetings of the Audio Engineering Society anytime soon. But are audiophiles – even the scientific community – ignoring at their own peril on what we can learn about the phenomena behind now polarized water works as a hi-fi tweak?

The polarized water referred to by hi-fi enthusiasts is a north-polarized water that is produced as a result of exposing a bottle or glass of water – usually around 250 to 500 ml – to the north magnetic pole of a magnet (the one marked “N”) for around 2 to 5 minutes. The stronger the magnet, the better. Most recommend drinking the water to make your audio gear sound better. But if we do it this way, does it mean that polarized water is a tweak for the listener, as opposed to the audio component being listened to?

The science behind how polarized water works – and it does work to some degree – has yet to be determined. But there have been recent studies conducted on water that woefully revealed that there is still a ton of stuff that the layman and the scientific community doesn’t know about water – let alone polarized water. Professor Eshel Ben Jacob, a physicist from Tel Aviv University, whose research on water memory after it is exposed to electromagnetic radiation when he noted that the bacteria in the water manifested the memory properties of water that is being exposed to such electromagnetic radiation.

Prof. Jacob recently uncovered during the course of his research that water is capable of carrying complex information despite of its “apparently” simple molecular structure. The preliminary findings of the professor’s research suggest not only a scientifically verifiable explanation behind the phenomena of homeopathy, but also on a new paradigm of water purification.

Something that is less stressful after Prof. Jacob had found out that stressful water purification can cause unnecessary stress in humans and other organic systems. Does this suggest that Prof. Eshel Ben Jacob’s findings suggest that water is capable of carrying information / properties that humans – maybe some who are perceptive enough – can perceive even though our most sophisticated mass spectrometers cannot?

Back in 1994, I was fortunate enough to hike into a remote watershed in my neck of the woods – a 12-hour “ordeal” from the nearest roadside – and managed to witness something that water supposedly can’t do. Bamboo harvesters accidentally left some bamboo in the pool that formed at the base of a pristine spring often used by them as a convenient “watering hole”. Bamboo cuttings aren’t supposed to sprout into a new plant right? But here, an obviously machete-cut section of bamboo managed to sprout roots and stems after being immersed for more than a week in the pristine pool of a remote mountainside spring – another thing water doesn’t supposed to do. Though I kept away from that place because where I came from, if there’s a near-inexhaustible supply of really clean and free drinking water, there are bound to be well-armed insurgents. But I still remember the inextricably invigorating properties of the water from that particular spring.

Another proof that the human senses are more sensitive than the most advanced mass spectrometer was shown in an episode of Mythbusters. On this particular episode, the Mythbusters team tries to prove that through using charcoal filters used to purify water a cheap low-end vodka can be used to taste like top shelf or high-end vodka. The charcoal filter made the cheap vodka taste much closer to top shelf vodka via charcoal filtration. Inextricably though, the mass spectrometer – which was used during the episode to analyze the various grades of vodka - can’t tell the difference between the cheap vodka, the charcoal-filtered cheap vodka and the high-end / top shelf vodka. The mass spectrometer only show water-diluted ethyl alcohol while a professional vodka tester and even novice bar hoppers can tell – make that taste and smell - the difference between cheap vodka and high-end vodka. So the lesson here is trust your senses, they are better than a 20,000 US dollar Fast Fourier Transform signal analyzer or a 50,000 US dollar nanogram-level mass spectrometer.

As Professor Eshel Ben Jacob pointed out the science behind a newly-discovered mechanism still under investigation that stressful purification of water does make most humans who consume them stressed out. Maybe exposing stressfully purified water to the North Pole of the magnet for 2 to 5 minutes de-stresses it. Making one drinking the water more musically receptive thus enabling polarized water to work as a hi-fi tweak in improving the sound of your audio system.

Much Ado About Slew Rate

2009-11-24T02:29:00.000-08:00

Given that most audio equipment manufacturers seldom – if ever – publish the slew rate ratings of their audio amplifiers, how important does an amplifier’s slew rate rating affect its performance?

By: Ringo Bones

After having the good fortune of visiting a good number of hi-fi shows in the past, I do find it odd that an overwhelming number of audio amplifier manufacturers seldom – if ever – publish the slew rate ratings of their preamplifiers and power amplifiers that they are trying to sell. Of probably thousands of brands and manufacturers out there, I only discovered six audio amplifier products so far that published their slew rate ratings. They are: 1.) Creek 4330R Integrated Amplifier at >40 volts per microsecond, 2.) Audio Research VTM200 Monoblock Power Amplifier (vacuum tube-based) at 40 volts per microsecond, 3.) Audio Research VT200 Power Amplifier (also vacuum tube-based) at 25 volts per microsecond, 4.) Simaudio Moon Rock Monoblock Power Amplifier (solid-state) at 160 volts per microsecond, 5.) Headroom Reference Amplifier Module – a power amplifier for headphones – at 1,300 volts per microsecond, and the 6.) Cinepro 3k6SE Six-Channel Amp with a slew rate rating of 65 volts per microsecond. Given that an amplifier’s slew rate rating is probably the last thing on a typical hi-fi audio amplifier buyers’ mind, what is slew rate anyway and how much of a factor does it play in a typical audio amplifier’s performance?

Slew rate is defined as the rate of change of the output voltage of an amplification circuit. Typically it is expressed as the maximum rate at which the output voltage of an amplification circuit can change in volts per microseconds. If an amplifier, for example, has a slew rate of 1 volt per microsecond it would take 10 microseconds for the output voltage to change from 0 to 10 volts, regardless of the rate at which the input voltage changes. Slew rate ratings also define the bandwidth capability of a typical amplifier design. An amplifier can only amplify a sine wave without distorting it up to a certain frequency as dictated by its slew rate rating. If a sine wave is of too high in frequency for an amplifier to process without distorting it given the amplifiers’ slew rate rating, that amplifier would output a triangular wave signal of higher amplitude instead of a sine wave. Triangular waves contain mostly odd-ordered harmonics by the way.

Audio engineers who would rather “listen” to their amplifier with 10,000-U.S. dollar Fast Fourier Transform analyzers instead of their very own ears tend to disdain in measuring the slew rate of vacuum tube-based amplifiers – especially single-ended triode amplifiers with vanishingly low to zero negative feedback. Because the squashing transfer function typical in these amplifier designs can decrease the odd-order harmonics in the signal they are trying to amplify. A triangular wave being fed into a tube amp’s input may end up looking like a sine wave with a higher magnitude at the output. A good thing about this typical idiosyncrasy of vacuum tube-based amplifiers is that it is not frequency dependent, unlike an audio filter with fixed frequency response. This is probably the primary reason why tube amps – especially ones that don’t use any negative feedback – sound musical and might – with the emphasis on might – give a misleadingly high slew rate rating in comparison to solid-state designs. Despite of all this, how does slew rate play a factor when it comes to the everyday use of our audio pre and power amplifiers?

If you’re fortunate enough to have peeked into a typical high slew rate hi-fi power amplifier, you might have noticed that the “apparent” complexity of its circuit layout and design just to achieve a high slew rate rating may seem a touch of glorious excess, but it is eminently practical. Today’s audio formats – if you’ve already managed to outgrow the typically compressed dynamic range of on-line digital music downloads – demands instantaneous power in order to amplify them realistically as Mother Nature or God in Her infinite wisdom intended.

Since the mid-1990s, the SMPTE movie-soundtrack specifications now permit special effects to peak 20 decibels above the average dialogue level, thus requiring 100 times more amplification power than is needed for dialogue. Using the watt-meter setting of my multi-meter, the average dialogue levels of the DVD of the movie Independence Day in my listening room with my audio system required only 1 to 3 watts of power. But during one of the loudest part of the movie – when the alien saucer blew up the White House – my main amplifiers generated a peak of 250 watts for probably half a second.

This performance – paradoxically - was produced by my 70-watt rated power amplifier equipped with a 300-watt power supply sporting high-speed Schottky Diode / Schottky Barrier Diode rectifiers with Rubicon Black Gate capacitors. This is at a sound pressure level in my listening room that doesn’t preclude casual conversation given that my main speakers has a sensitivity of 93 watts at 1 watt (2.87 volts) at 1 meter. What I’ve learned so far is that not only do you need clean power, you also need it fast in order to produce current music or other audio formats realistically. Though in my case, I tend to gravitate towards the sensitive loudspeaker route. Nonetheless, slew rate ratings is a very important factor indeed when it comes to the realistic sounding playback of recorded music - and movies - in a domestic setting.

Memory Distortion: The Bane of Solid-State Amplifiers?

2009-10-28T05:39:00.000-07:00

Some audio purist still claim that solid-state amplification is not truly hi-fi in comparison to it’s thermionic / vacuum tube counterpart, is there a reason behind this?

By: Ringo Bones

During the start of the 1970s, the solid-state transistor-based audio power amplifier started to make the price of high-powered hi-fi amplifiers – i.e. over 50-watts – much more affordable. But many hardcore audiophiles complained that transistor-based audio power amplifier didn’t sound as musical as their thermionic / vacuum tube-based counterparts. Even newer MOSFET devices – whose characteristic curves resembles that of a pentode tube – still didn’t sound quite as musical in comparison to their thermionic brethren during their rollout near the end of the 1970s. But is there a reason – hopefully a scientifically verifiable one – that explains why solid-state amplification (transistors and MOSFETS) don’t sound as good as their vacuum tube counterparts?

Back in the summer of 1997, a French amplifier manufacturer – Lavardin Technologies – announced that they have discovered why solid-state amplification didn’t sound as musical as their vacuum tube-based competition. They called the phenomena “Memory Distortion” which Laverdin Technologies describes it during 1997 as “the greatest discovery in analogue audio design in the previous twenty years”. Memory distortion, Lavardin Technologies says, is responsible for the shrillness and mechanical-sounding artifacts identified in solid-state amplifiers. Unfortunately in the intervening years, my “richer” audio-buddies can only listen to Lavardin Technologies’ amplifiers in hi-fi shows because they are so prohibitively expensive when compared to vacuum tube-based amplifiers of similar power output and features. But they swear that Lavardin Technologies' low-powered integrated amps do sound like they use vacuum tubes as power output devices.

Fast-forward in 2009 when one of my audio-buddies managed to purchase one used – although still very costly – one of those Lavardin Technologies integrated amplifier. It is the 30-watt Lavardin IS Reference which sells for almost 4,000 US dollars when brand new. He got one for a shade under 2,000 US dollars, and say’s its all worth it because the single-pair of transistors used in this integrated amp will last for thousands of years when properly used. And they do sound like vacuum tube amps – vacuum tube amps that could drive speakers with tricky impedance curves. Albeit only within their “meager” 30-watt rating. But despite of the obvious overpricing in electronics engineering terms, why do these amps sound so good?

Given our sample no longer has the company’s warranty and my audio-buddy was generous enough – albeit up to a point – to allow our local hi-fi association a peak inside the innards of Lavardin’s famed integrated amps. A look inside might make every “mainstream” electronic engineers accuse of Lavardin Technologies of recto-cranial inversion. Those mainstream folks usually accuse everyone of encasing the circuits of their designs in some kind of black goop in the name of copyright protection, as suffering from recto-cranial inversion. But these has been proven – probably since the 1980s – that it could improve the sound quality by controlling spurious vibrations from affecting the sensitive circuit layout.

Lavardin did divulge the reason why tubes sound better than transistors, which they used to their advantage in making their solid-state amplifiers sound as good as tubes. It was probably the consensus view of quantum physicists who looked into the differences in operation of vacuum tubes and solid-state devices during the 1990s. According to their findings – though it has been noted in every post World War II vacuum tube-based electronic textbook in existence – which start at the basic fundamental differences between vacuum tubes and solid-state devices.

In a vacuum tube any particular electron – i.e. strictly speaking the electron’s wave function – travels through free space, influenced only by the electric fields caused by the various electrodes in the electron’s wave function’s path within the confines of the tube. The control grid’s field hold’s back a proportional number of electrons from the total number of electrons emitted by the cathode, in which a change in grid voltage change’s it’s field and thereby varies the total number of electrons reaching the anode and hence the resulting anode current.

The velocity of an electron by the time it reaches the anode after being accelerated by the anode’s field is truly mind-boggling. As an example, a tube with a typical anode voltage of 450-volts, the electrons will hit the anode at approximately 28 million miles per hour or about 4% the speed of light – which is around 670 million miles per hour in vacuum. Thus the reason for the vacuum tube’s somewhat high-temperature operation. The electrons which make it past grid are the same ones which – a tiny fraction of a second later – appear at the anode and becomes the signal that drives the load.

In a solid-state device – transistors, MOSFETS, and specially including wire – the electrons have a very hard time traversing the entire length of their intended path. In the solid-state domain, electrons have to fight their way through millions of random fields caused by the atoms in the substrate material – usually at 0.001 meters per second. In which calling it a snail’s pace would be an understatement in comparison to an electron’s speed traveled though a typical vacuum tube. Furthermore, it is not the actual electrons which carry the signal, but the influence one electron on it’s neighbors. The message or signal gets carried akin to a “Chinese Whisper” albeit only with less degradation of the signal – hopefully.

This quantum-mechanical explanation of the radical difference between vacuum tubes and solid-state devices is the claim used by Lavardin in explaining how they minimized memory distortion in their solid-state amplifier designs. According to them, memory distortion has to do with the way musical signals have to slog their way through silicon – akin to being stuck in the mud. Transistors hold previous signals in memory – as in the electron’s wave function. And these “residual memories” or remnants of an electron’s previous state - maybe a few tiny fractions of a second before distort the new incoming signals. The musical signals can’t flee the silicon fast enough. But is this explanation sufficient from a scientific standpoint? After all, if “memory distortion” is about timing errors – assuming that the phenomenon is real in the first place – then why is it that there are several, albeit almost unrelated, ways of eliminating the symptoms caused by memory distortion.

James Henriot of Whest Audio also managed to do the same feat of making solid-state amplifiers more musical by eliminating “analog-domain jitter” via his Whest dap.10 processor. Which most users testify that the Whest dap.10 processor improves their already well-sorted CD playback system’s sound quality by making it sound like a big analog open-reel tape, the one often used in better recording studios. I’ve heard this only in hi-fi shows, but my impression of this product seems like it makes your typical solid-state integrated amp sound like a good vacuum tube amp.

While a Frenchman named Yves-Bernard André of YBA also manages to do the same with his solid-state integrated designs by using various techniques holistically to eliminate the symptoms that make solid-state amplifiers sound “inferior” to their vacuum tube counterparts. From using synthetic diamond powder to damp the circuit boards to the resonance control of every component used. Not to mention minimizing to the absolute minimum the inherent hystersis distortion caused by a transistor’s ferromagnetic enclosure. Even though YBA products – as with most French integrated amps - are typically priced way above a typical hi-fi enthusiast is willing to pay, Yves-Bernard André’s holistic approach to designing his solid-state based audio components seems to have removed the symptoms of what we know of as memory distortion.

LFD Mistral MOSFET-based integrated amplifiers also managed to eliminate the symptoms of memory distortion through attention in circuit layout. By orienting the resistors of their LFD Mistral integrated amps in phase on the master board. The resistors on both channels are identically oriented which they believe – and some owners of LFD Mistral integrated amps – is important to stereo imaging. So does the orientation of the wiring and the fuses. Unfortunately, this attention to detail in parts layout doesn’t lend itself well to mass production machinery used in making mobile / cellular phones and i-Pods. But the resulting product is nonetheless spectacular. LFD Mistral integrated amplifiers are often compared to single-ended triode amplifiers in terms of sound quality.

So what does this all mean? Well, it seems like the holistic tweaking techniques utilized by Yves-Bernard André and the LFD Mistral does seem to improve the sound quality of your typical solid-state audio gear – even ones using integrated circuit IC amplifiers. While the Lavardin Technologies may be on to something in explaining the phenomenon of memory distortion, James Henriot’s forays into analog-domain jitter will probably need the collaboration of other scientist with access to the very state of the art testing gear to explore further the phenomena of analog-domain jitter. Who knows that it might result in better and cheaper laptops and mobile phones ten years from now? Maybe memory distortion is just a symptom of bad circuit layout in the production of solid-state gear. Often easily solved via enclosing critical parts in a faraday cage - or by the use of exotic and boutique capacitors like Rubycon Black Gates or Philips-sourced French Blue capacitors.

Is the BBE Sonic Maximizer Hi-Fi?

2009-09-22T17:45:00.000-07:00

Manufactured during the mid 1980s supposedly as a means to “transcend” the limitations of hi-fi speakers at that time, does the BBE Sonic Maximizer qualifies back then – and now – as hi-fi?

By: Ringo Bones

Now (as in 2009) derided by hardcore audiophiles and “soulful” electric guitar players, I did remember during my high-school days – i.e. the mid 1980s – that a black box with the letters BBE was both revered and coveted in domestic hi-fi circles in my neck of the woods. To the uninitiated – and those who have already forgotten – here’s a refresher of that used to be wonderful black-box known as the BBE Sonic Maximizer.

The letters BBE stands for Barcus-Berry Entertainment Incorporated – later called BBE Sound Inc. when they’re “iconic” black-box / audio processor that became widely used and endorsed by Heavy Metal musicians during the “Hair Metal” era of the late 1980s and early 1990s. The company is located at Huntington Beach, California. Around the middle of the 1980s, BBE Sonic Maximizers began to be widely used for audio recording, motion picture sound tracks, TV and radio broadcasting, and motion picture theatre sound systems. According to the audio processor’s creators, BBE Sonic Maximizers were primarily designed to improve the sonic clarity of virtually any reproduced sound by correcting / compensating for phase and amplitude distortions produced as your typical power amplifier drives a typical loudspeaker system.

My first hand experience of this device was back in 1987 when a rich high-school classmate with similar musical tastes as me got one from his dad while working in the US. It was the Barcus-Berry BBE Model 2002 signal processor, which sold around 500 US dollars at the time. The BBE signal processor was meant to be installed between the signal source(s) – we only had a cassette tape deck and a Technics Quartz Synth tuner at the time – and the power amplifier.

Though my memories of that particular BBE Sonic Maximizer was now somewhat hazy, I can still vividly remember that we often played a track called Digital Bitch by W.A.S.P. (We Are Sexual Perverts?) at the time - Unforgettable because Chris Holmes, Blackie Lawless and the rest of the band probably foresaw the rise of Paris Hilton and her famous antics on the Internet. And as one of the few Heavy Metal bands who gained a strong following in the Punk community – my high-school classmate was actually into Punk / New Wave at the time – W.A.S.P. gained fame (or is it notoriety?) in both camps. Rumor has it that W.A.S.P. were “discovered” by Ed McMahon during the first season of Star Search.

From my present perspective – being my present hi-fi set-up is composed mainly of Electro-Harmonix vacuum tube-equipped and high-speed wide-band solid state exotica. All I can say is that the BBE Sonic Maximizer is nothing more than a “lazy-EQ”. I mean it is just an adjustable Loudness controller on steroids – though I am not denying that it is not useful. Given that at the time, we can rarely crank up our hi-fi sets to “unamplified / no PA system” garage band sound levels. Those rare occations when we can play as loud as possible during my high-school days is usually reserved for band practice.

When you can only play your hi-fi below the actual sound pressure level the music was originally recorded, Loudness and other EQ / tone controls to compensate the Fletcher-Munson Equal Loudness Contour Curves inherent to how our ears perceive airborne sound. To my ears – back then as it is now (2009) – BBE Sonic Maximizers boosts the bass and treble frequencies of the audio signal, depending on how much it’s “process” knob is being cranked.

First impressions on using the BBE Sonic Maximizer usually results in “clarity” – i.e. the boosting of the high-frequency signals usually around 2-KHz to 3-KHz upwards. And this is why many novice hi-fi enthusiasts during the early 1990s who can only afford mass market mini component boom boxes to listen to their copies of Smells Like Teen Spirit by Nirvana became concerned over “tweeter failure”. Especially when the tweeters of their BBE-equipped boom boxes (which became commonly widespread around 1992) heats up when playing the iconic “Seattle Grunge” album that features very distorted electric guitar sound with boosted high-frequencies.

Due to its endorsement and use by top musicians, like Megadeth and Skid Row – guitarists Dave “The Snake” Sabo and Scotti Hill were known to use one - during the early 1990s. The folks at BBE Sound Inc. created a BBE Sonic Maximizer plug-in for PC-based recording, which started to gain popularity during the late 1990s. For domestic hi-fi use, the BBE Sonic Maximizer works very well with budget cassette tape decks that don’t carry the Nakamichi badge to make them sound more “natural”. BBE Sonic Maximizers also works very well to "improve" (...or is that to flatter?) the “sound quality” of FM stations that are seriously addicted to those OPTIMOD compressors. And data reduced digital music downloads like MP3s. But if it is up to me, I would rather use the vacuum tube-based Pultec Model EQP-1R studio equalizer. This vintage studio equalizer - probably dating back to The Beatles era Abbey Road Studios - has 12RX7 and 12RU7 preamplifier vacuum tubes that can put to shame the BBE in sound quality terms.

Unfortunately, BBE Sonic Maximizers are an anathema to vacuum tube hi-fi aficionados and “soulful” electric guitar players because they tend to make their gear sound like cheap solid state. Like a brand new 10,000-watt audio power amplifier with a manufacturer’s suggested retail price of 200 US dollars. Surprisingly, BBE Sonic Maximizers can often be found in pawnshops or other establishments that sell pre-owned music gear somewhere between 50 to 100 US dollars. So it is somewhat a cost-effective way for the curious and uninitiated to experiment – or experience first-hand - what this BBE audio processing brouhaha is all about.

An Op-Amp IC For Your Hi-Fi Needs?

2009-09-14T18:15:00.000-07:00

Given that they’ve been used successfully in a number of excellent sounding hi-fi applications, is there really a right op-amp for your audiophile needs out there?

By: Ringo Bones

Yes it’s true, there really is such a thing as an audiophile grade integrated circuit operational amplifier or IC op-amp. And most of them are not necessary manufactured by Analog Devices like the AD845 and AD843. Or those by Burr-Brown which their dual op-amps that are specified to be fast enough to handle the RF energy present in Red Book CD digital to analog conversion are often used in bridge configuration in left / right analog outputs.

The quest for finding the best off the shelf IC op-amp probably started during the early 1990s. When major CD player manufacturers discovered – either by theoretical introspection or trial and error – that those high-speed op-amps made their 500 US dollar or so CD players sound closer to entry-level audiophile grade vinyl LP replay.

From the electronic engineer’s design standpoint, high-speed op-amps are a necessity in Red Book specification CD players. Sufficient slew rate ratings are a necessity to handle the quite large amounts of ultrasonic requantization noise - which is an unfortunate by-product of converting your 16-bit 44.1-KHz digital data into a reasonably smooth analog waveform that could sufficiently past muster as music. In my experience with the most widely used up-market “hi-fi” op-amps – namely the LM318 and the LF356 – which have very different personalities when used in an audiophile context. Although I used audiophile grade ceramic IC sockets with silver connectors to allow me to easily replace both op-amps for comparison.

Over the years, my countless experiences with the high-slew rate (50 volts per microsecond) LM318 suggests that this IC op-amp is well suited to audiophiles who like to listen to Classical Music - Or wants to reproduce the recorded hall acoustic of an opera recording accurately played back in his or her listening room. It even enhances – or exaggerates – the Classical Music-like hall acoustics of some tracks of The Gathering’s “How To Measure A Planet?” album.

One drawback of the LM318 op-amp though is that it doesn’t like very much the “relatively” high-capacitance interconnects often used in entry-level solid-state audio gear. Like Monster Cable’s mellow sounding M850i interconnect often used to tame the harshness of cheap solid-state audio systems. Resulted in a high-pitched squealing sound on rare occasions (guaranteed more than once) during turn on. Although easily remedied by turning off and turning on again your entry-level solid-state amp.

Even though from a technical standpoint, the LF356 has a much lower slew rate rating (12 volts per microsecond) in comparison to the LM318, it does audiophile-oriented things that the LM318 can only aspire to. The very high input impedance – about 1 trillion ohms - of the JFET input stage of the LF356 allows it to have a bass response that Rock Music aficionados since the time of Elvis strive for. The LF356 is also capable of driving large capacitive loads – up to 10,000 picofarad or 0.01 microfarad – with ease. Which makes it more suitable for driving high-capacitance mellow sounding interconnects used in entry-level solid state gear.

Sound quality wise, it is as if the designer of the LF356 op-amp want it to sound like what recording engineer Andy Johns wants the first four album of Led Zeppelin to sound like – i.e. the “John Bonham snare sound”. The LF356 also sound as if it is the first op-amp with a very musically ideal loudness control. It defeats the Fletcher-Munson contour curve characteristic of the human ear that makes us less sensitive to the bass and treble frequencies when listening at reduced sound volume levels. With the LF356, you’ll get the full works whether you’re playing at 65dB or 95dB sound pressure levels - not unlike the sound of Electro-Harmonix versions of 12AX7 preamplifier tubes.

Surprisingly, the LF356 does room sound too - Although not like the Classical Music concert hall portrayed by the LM318. The room sound produced by the LF356 is the “normal” unadorned type – typical recording studio or just a spacious venue. The LF356 also has better low-level sound retrieval in comparison to the LM318 because the LM318 tends to exaggerate the dynamic range of CDs that are recorded without Tom Lord-Alge levels of compression. Like Lunachick’s Binge and Purge album which the LF356 still manages to retrieve low-level details that are played back even softer by its higher slew rate counterpart.

Both can still benefit from a well-regulated plus and minus 15 volt split supplies though, given the inherent RF corruption of our contemporary power lines. Despite both IC op-amps often rated with a power supply rejection ratio of over 100dB at 50 to 60-Hz AC. Boutique capacitors like Rubicon Black Gate capacitors or Philips sourced French Blue capacitors also help improve sound quality to no end.

So there you have it, two op-amps that I have extensive experience with that could past muster as being audiophile certifiable. Although it is somewhat over simplistic to conclude that one prefers Rock, while the other op-amp prefers Classical. The sound quality of one is sufficiently different from the other that it is worth noting. Although the LF356 also has a gorgeous presentation with Orchestral Classical Music recorded during the Golden Age of Stereo.

Are Integrated Circuit Operational Amplifiers Hi-fi?

2009-09-07T18:04:00.000-07:00

In the current fashion “revival” of vacuum tube and discrete transistor usage in the hi-fi scene, are audio designs that use integrated circuit op-amps still considered hi-fi?

By: Ringo Bones

Integrated circuit – or IC – op-amps have a myriad of advantages over their discrete component-based counterparts other than space. Like extremely high input impedance, high common mode rejection ratio and high power supply noise rejection ratio just to name a few all in a very compact package. But in terms of ultimate sound quality, many top designers in the hi-fi world find the sound quality of most IC op-amps wanting.

Richard Fryer, founder and owner of Spectral Audio – one of the top manufacturers of cutting edge solid-state audio gear, who as recently as 1998 still insist on using discrete circuitry. As opposed to integrated circuit chips much of the time. Fryer and his design team at Spectral Audio had found out over the years that for critical signal applications, integrated circuits – or IC chips to you and me – simply don’t meet their quality standards. Although he and his design team had been constantly evaluating new integrated circuits and, to everyone’s credit, the IC chips are getting better and better through the years. Still in the rigorous evaluations that the design team at Spectral Audio does these “improved” IC chips simply can’t pass the microphone feed accurately. There’s so much musical information and life that is lost – according to Fryer. Even with the most premium integrated-circuit amplifiers, these integrated circuit packages are just not up to Spectral Audio’s needs in critical signal applications.

Even though most audio designers in the hi-fi world still insist on using discrete components, there are those who are adventurous enough to use IC op-amps in their cutting edge audio designs. Ron Sutherland is one of those high-end audio gear designers who isn’t afraid to use IC op-amps in his almost 7,000 US dollar Sutherland PH-1 phono preamplifier. Maybe it is because Sutherland has a degree in both electrical engineering and physics that made him courageous enough to use a number of Analog Devices instrumentation integrated circuit op-amps on his somewhat “pricey” but very good sounding phono preamplifier.

Another upmarket high-end audio gear that uses IC op-amps is Reflection Audio Design’s 4,700 US dollar (550 US dollar extra for a phono stage) OM1 preamplifier. The OM1 preamplifier is a high-speed, super wide-bandwidth design based on very high slew rate IC op-amps rated at 2,000 volts per microsecond slew rate. It is purported to be flat to 2 megahertz and able to maintain an absolute phase of plus and minus 0.5 degrees across the audio bandwidth (20 Hz to 20,000 Hz). The OM1 preamp by Reflection Audio Design is a very pretty two-chassis affair – if you include the matching 1,550 US dollar battery unit – with a high level of attention to detail. Like the use of curved circuit traces to avoid high-frequency signal reflection.

There are also budget high-end audio designs that used IC op-amps. Like the Super Pas 4 i preamp kit which famed Dynaco tube amp tweaker Frank Van Alstine sold in the early 1990s. Though this preamplifier is somewhat unique because it is a tube and op-amp IC hybrid. Comprising of two 12AX7 tubes and two AD845 (AD843) FET input op-amps in the output stage. And it is surprisingly affordable – in high-end audio terms – at 595 US dollars back in 1993.

In my personal experience, op-amp IC chips – when used properly – can achieve excellent results sound quality wise. Sometimes I wonder why all brand-name boom boxes being flogged in the “high-street” can’t achieve excellent sound quality that matches even cheap DIY hi-fi that uses op-amp chips. Even DIY-ers had achieved excellent results with these lowly audio devices. Most of these serving as a gateway to the wild blue yonder of high-end audio. Next time, I’ll be discussing my experiences with the most touted op-amps for audio use, the LF356 and the high slew rate LM318 in a DIY hi-fi context – replete with unapologetic tweaks.

Does Cranking the Bias Current Make a Better Tube Amp?

2009-08-09T18:40:00.000-07:00

Many swear that it improves high frequency performance, but does cranking up the bias current a sensible way to improve high frequency performance of your tube / valve amplifier?

By: Ringo Bones

This thorny issue started in my neck of the woods during the tube / valve amp revival of the mid-1990s. Where everyone with a still-working 6L6-equipped 1965 Fender twin of a EL34-equipped Marshall amplifier found out that these rock guitar workhorses can be made into very righteous hi-fi amps by jacking up the output tubes’ bias currents and connecting them to domestic hi-fi loudspeakers. And after the news arrived that a fresh batch of tubes / valves are only a plane ride away in neighboring Hong Kong, thus turning every tube-based guitar amp toting guitar hero wannabe curious about hi-fi into ad hoc tube / valve electronic experts almost overnight. The frenzy of everyone in my place born way after astronauts Armstrong and Aldrin first walked on the surface of the Moon scrambling in a Manhattan Project-like zeal to make their tube-based guitar amps do double duty as audiophile quality hi-fi amp-on-the-cheap. Is probably the most surreal manifestation of anachronism I will ever see in my entire life, but does the price of their blissful ignorance worth more than they bargained for?

11 years ago (in 1998), I was in the process of fulfilling my personal tour-de-force of constructing a Black Face Fender Champ on steroids. It was a single-ended guitar amp based on the Russian GM70 transmitter tube / valve that I found for sale rather cheaply – 2 for 15 US dollars – in a garage sale. This rather “gigantic tube” has an anode dissipation of 250 watts and requires a power supply of 1,500 volts DC. The only “substantially expensive” parts of my Black Face Fender Champ on steroids was an output transformer by Audio Note that can handle the GM70’s 1,500 volt DC power supply brought used from an “disenfranchised” hobbyist for about 50 US dollars. And a Japanese-sourced OEM Leslie-type organ speaker cab from the 1970s being heavily discounted by our local flea market because no one ever bought it since it went on display back in 1979. The flea market’s storekeeper very gladly sold it to me for about 20 US dollars. Luckily the other components required for my project amp had been lying around in my spare equipment trunk. It wasn’t long before someone in my neighborhood haggled me to part with it for about 1,000 US dollars.

At the time this was a very good deal because I’ve only probably spent about 250 to 300 US dollars creating my ultimate guitar amp, plus I desperately needed the money to bribe into a lucrative government job to pad my résumé. Sadly the new owner began cranking up the output tube’s bias current to accentuate the Black Face Fender Champ on steroids’ very beautiful high-frequency timbre. Allowing the big tube to fail 7 months later. Coming to his senses, he backed up the bias to normal and the “spare” GM70 tube still played to this day (2009).

By their very nature, tube-based electric guitar amplifiers don’t work particularly well as uncompromising audiophile-grade domestic hi-fi amplifiers. Especially if the musically-inclined user discovers the “virtues” of reducing the negative feedback levels of his or her electric guitar tube amp as a hi-fi amp set-up. Though zero-feedback tube / valve amplifiers are well known for retrieving the subtle nuances of the acoustic environment of recorded music, redesigning your guitar amp’s negative feedback to zero could destroy the tweeters of your domestic hi-fi loudspeakers. Especially since an overwhelming majority of guitar amplifiers output transformers are not purposefully wound to work in a zero negative feedback tube-based amplification circuitry. Let alone designed using a Fast Fourier Transform.

EL34 equipped Marshall amps are the most often tweaked by this method to adopt them for domestic hi-fi use. Most of these types have an H.T. of about 440 volts DC when measured between the plate (pin 3) and the cathode (pin 8) of the EL84 tube / valve. Most EL34 push-pull power amplifiers are fitted with access pins / ports where you can insert the + and – test terminals of your voltmeter / multi-tester / multi-meter to allow you to adjust the bias current of each tube. Usually this is composed of a high-wattage 10-ohm resistor – usually designated as Rs and is connected from the pin 8 of a particular EL34 to the circuit ground. When you attach your voltmeter at this test point, it is effectively in parallel to an internal 10-ohm resistor or the Rs resistor.

Setting your voltmeter / multi-tester to the 1-volt range, if the voltage reading across this point is 500-millivolts or ½ volt, you can use ohms law to compute for the bias current of the particular tube you are measuring – i.e. current = voltage / resistance. Which at 500-millivolts / 10-ohms = 50mA or 50-milliamperes of standing current or bias current. Using this data, you can now compute the EL34 tube’s power dissipation in the amp you are testing. Using Ohm’s law formula to obtain power P=IV or P = 50mA multiplied by 440 volts = 23 watts, which will be the power dissipation of the EL34 tube as used in the particular amplifier design you are measuring. Though the voltage of the H.T. and the resistance value of the Rs resistor could deviate by as much as 10% during normal use.

From a design standpoint, the EL34 tube / valve and its derivatives – like the 6L6, KT77, KT88, 5881, 6550, 6CA7 tubes – were rated by their original manufacturers during the “Golden Age of Stereo” for a maximum anode dissipation of 25 watts and exceeding this rating will drastically shorten tube / valve life. This is so because the excess heat generated by exceeding the tube’s anode dissipation will cause the anode to release what is known as occluded gas, which damages the delicate cathode coating reducing electron emission. Some types of EL34 tubes / valves – especially ones manufactured in Eastern Block countries and China during the 1980s – may also have a low emission to start with and cranking up the quiescent bias current / standing current could cause the tube / valve to saturate on peaks / high-level signals, causing distortion.

Many veteran tube / valve amplifier designers suggest that if you are after extended output tube life, you shouldn’t run EL34-type tubes at over 20 watts of total anode dissipation to lessen the heat generated inside the tube / valve. Unfortunately, cranking up the bias current on these types of tubes usually results in an “improvement” of their high frequency response – i.e. a subjectively much louder high-frequency sound output. Which can be addictive when it comes to tube amps because of their really sweet and grain-free presentation of high-frequency audio information. Some are even known to crank up the quiescent bias currents of the tubes of their EL34s up to 85mA, making the tubes less likely to last more than eight months when use at an average of eight hours a week.

If you want to make the high-frequency response of your tube-based electric guitar amp “seem” louder, do what Queensrÿche does during the late 1980s. Replace the 12-inch Celestion speakers of your Marshall cabs with JBLs. Or if you can afford them 15-inch Leslie-derived organ speakers equipped with a whizzer cone similar to the one used by Jimi Hendrix when he recorded Little Wing in the studio back in 1967.

For those with a more thorough knowledge in tube / valve-based electronics, another method of increasing the high-frequency output of your tube-based electric guitar amplifier is to modify the preamplifier section. The majority of tube-based guitar amps being sold today still use the “conventional” 12AX7-based double-triode phase splitters in their preamplifier sections. The problem with the conventional double-triode phase-splitter is it’s high input capacitance caused by the Miller Effect. This causes high-frequency loading on the input (12AX7-based?) tube and reduces bandwidth, making it very difficult to use appreciable amounts of negative feedback - especially with 6L6 Beam Power Tetrode and EL34 Pentode output tube designs – without instability due to the phase shifts incurred. By the way, negative feedback is a necessity when extracting the maximum output power obtainable of relatively “modern” output power tubes like the 6L6 and the EL34.

Low noise R.F. pentode preamplifier tubes can be used as a better phase splitter in the preamplifier section of tube-based electric guitar amps because a pentode has a very low input capacitance and high gain due to the shielding effect of the screen grid. This means that the capacitance loading on the input tube (12AX7) is greatly reduced, increasing bandwidth and decreasing troublesome phase shifts.

Or if you want the ability to experiment lowering the negative feedback of your electric guitar amp or operating the output power section in triode mode without your amplifier breaking into spurious oscillation. Which could destroy tweeters when you used your tube-based guitar amp as an ad hoc hi-fi tube amp, then use beefier preamplifier tubes like the 5687 tube. The 5687 tube can dissipate 4 watts, it’s dead linear, needs less drive current, and has a low output impedance. Making it able to be used as a driver stage of an inter-stage transformer (Does this remind you of the AN214 driving the inter-stage transformer of an MJ2955-based transformer-coupled booster amp?). If you go with this redesign route, the output tubes of your guitar amp could be configured in self-biased or auto bias mode due to the secondary winding of the driver / inter-stage transformer as opposed to their de rigueur fixed bias configuration.

Auto bias has the advantage of providing automatic compensation of tube variability characteristics, so tube matching and individual bias adjustment will no longer be necessary. Though matched pairs of tubes are still desirable. Auto bias gives that sweet, easy sound tubes possess. Fixed bias gives more power, but a harder sound. In my experience, output tubes of auto-bias configured tube amplifiers tend to last forever. My neighbor’s 300B-based auto-bias amp still uses tubes that he purchased back in 1996 without any degradation in sound quality.

Another way of retaining the de rigueur double-triode preamplifier – i.e. 12AX7 tube-based preamplifier – of your guitar amp is by selecting an output tube designed with a higher mu or a high mu version. I have tried this in the past and it does work but it needs power supply / H.T. circuit modification of your guitar amp. The advantage of this route is that high-mu version of your typical output power tube – like the EL34 and 6L6 – are easier to drive, thus retaining the 12AX7 pre-amp tubes. The caveats include complete redesign of the power supply since high-mu tubes require higher supply voltages than the 450 volts DC needed by your typical output power tube / valve. Some of them needs the power supply / H.T. voltage to be raised to 1,500 volts DC in order to enjoy the maximum benefits of high-mu power tubes. Which can be a problem since power supply capacitors capable of handling 1,500 volts DC are somewhat rare, plus the output transformer needs to be changed to a type that can handle such voltage or your loudspeaker will be turned into a dazzling pyrotechnics display.

Though if you change the choke / inductor filtering the 12AX7 pre-amp tubes to one with a higher inductance – therefore higher DC resistance to lower the incoming voltage supplying the pre-amp tubes, the 12AX7 tubes will be fed with a highly-filtered H.T. DC voltage whose hum is now vanishingly low. Another caveat of this design route is that the output impedance of your guitar amp will now be higher than before – i.e. reduced damping factor – which your amplifiers tonality will be readily be affected by a loudspeaker with a widely-varying impedance curve across the audio band. Although guitar amplifiers that uses minimal amounts of negative feedback and high output impedance are known for their excellent musical performance, so you could probably design an electric guitar amplifier that could double as an excellent sounding domestic hi-fi audio amplifier using this route.

The Flat Earth Ideology

2009-07-21T17:41:00.000-07:00

Superseded during the 1990s owing to the increasing popularity of vintage low-powered tube amps and very sensitive loudspeakers, is the Flat Earth ideology a vital part of audiophile history?

By: Ringo Bones

Back in the middle of the 1980s, a prominent audiophile sect staunchly believes that the only boxes – i.e. loudspeakers – to have at the end of a righteous audio system should have the word "Linn" written at the back. This somewhat “extremist” hi-fi ideology was aided by enthusiastic hi-fi dealers of the period who are also audiophiles. Not to mention a certain since-defunct periodical / hi-fi magazine called The Flat Response. Thus allowing the hi-fi maker Linn to harbor the ideology that the first priority of a loudspeaker should be the way it played rhythms and the current long-standing global audiophile community’s perception of what is the British Sound was born. Though a Thomas Dolby song from the period titled “Flat Earth” is often played through these systems, reinforcing the need of spot-on rhythm and timing when playing eighties-era synthesizer-based music, but countless others probably use theirs to unravel the rhythmic complexity of Iron Maiden’s The Number of the Beast album.

The most uncompromising embodiment of this hi-fi ideology was the Kan, a tiny box manufactured by Linn. Equipped with treble and mid drivers similar to that used in Linn’s flagship brand the behemoth-sized Isobarik loudspeakers. Back around the middle of the 1980s, the Linn Kans was capable very captivating performance. These loudspeakers sounded extremely fast and extremely tight, with an “uncanny” ability to disappear into their own soundstage. Linn’s bigger – and more efficient – loudspeaker models never convincingly displayed the ability of the smaller Kan’s hi-fi slight-of-hand.

The Kan also has a profoundly fussy approach to matching ancillary components, ironically the little speaker’s “soul-mate” is an equally fussy solid-state power amplifier made by Naim called the NAIT that produced only 30 watts into an eight-ohm load. But during that era in the 1980s, the little Kan – if you wanted more than a squeak from these relatively inefficient speakers - was often paired up to a large muscular solid-state full complementary direct coupled amplifier with a power output of around 80 to 100 watts into an eight-ohm load. The hi-fi community’s renewed obsession with flea-powered tube / valve amps and Maytag washing machine-sized horn loudspeakers were still a decade away.

On the front-end side of things, Flat Earth systems didn’t like inferior source components. CD players circa 1983 was excruciatingly painful-sounding when played through the Kans, plus the early CD’s still suboptimally designed output filters produced so much rhythmic and timing anomalies that it negates the idea of having a Flat Earth system in the first place. Meaning in those days, it was Linn’s pre-braced plinth Valhalla LP12 with LVX+ and Basik cartridge, a Roksan Xerxes, or nothing.

The “dark side” of the Flat Earth ideology is that it made every audiophile – especially in merry old England – harbor the belief that tube / valve amps (especially low-powered ones) from the Golden Age of Stereo were deemed obsolete during the go-go eighties. The Flat Response hi-fi magazine didn’t helped matters either because reviewers of the Flat Earth disposition showed scant knowledge and interest when it comes to the science – and art – of loudspeaker matching. Using quintessentially 1980s era hard to drive loudspeakers with which most tube amplifiers played through them had to struggle. Maybe it was the sound of Leak Stereo 20s wheezing and groaning under the load of a pair of Linn Saras that many Flat Earth-leaning audiophiles conclude that tube amplifiers are now – in the mid 1980s – obsolete. Thus benefiting hordes of East Asian vintage audio enthusiasts.