Honest Audio Reviews

Glossary: Headphone Types

2011-04-13T02:46:00.001+01:00

Headphones are generally the most important piece of equipment in your portable audio setup although most people usually use the cheapest set possible and spend big on their playback device. There are various types of headphones coming in at a huge range of prices, all have their distinct advantages and disadvantages, and in this post we’ll be looking at each type.

There are 2 main groups of headphones these days, the large style ‘cans’ and the smaller ‘earphones’, we’ll start off looking at the larger of the 2.

Headphones

While large in sound they usually offer the most long term comfort, durability and are usually the best in terms of price : sound quality. You have 3 common types which are open, closed and semi-open, this simply refers to the cups. Open headphones have a grill in the back and let sound both in and out of the cups, they offer a natural airy sound and are usually easier to use for a long time without getting listener fatigue however they aren’t really suitable for use in noisy environments or around other people due to the isolation (or lack thereof). Closed headphones are the opposite of open, they usually have well insulated padding on the cups, and a solid back construction to stop sound leaking in or out, while they don’t sound as natural as open and usually muffle outside noises (which can lead to minor fatigue after long periods) they are perfectly suited to noisy environments and are commonly used by DJs, commuters and studios. Semi-open are the happy medium with the ‘open sound’ but with less leak, they do however still leak a significant amount and anyone in the surrounding area will be able to hear your music.

Earphones

Earphones are small and usually used for portable audio where space is a premium; they are generally more prone to damage and cost more for the equivalent sound quality in comparison to headphones. Earphones are split again into 2 categories, standard earphones and IEMs. Standard earphones are the type which sit just inside the ear but don’t reach into the canal; these types are being superseded by the more common IEMs which slot into the ear canal. IEMs have powerful bass, significantly better isolation and usually stay in the ears better than the older earphones, however they are also regarded as less comfortable although with modern IEMs and a good pair of sleeves IEMs can be more comfortable than the majority of earphones.

Zero 09 Version DAC/Amp

2011-04-08T13:41:00.004+01:00

Review: Zero 09 Version

Item: Amplifier (Headphone)

Price: £120

The Zero is a headphone amp made in Hong Kong, there really isn’t much info on manufacturer or anything else for that matter. The amps come with a couple of different options for op amps and inputs. On the op amp front the choices are OPA2604, the cheaper model, and OPA627 the more expensive of the two. For inputs on top of digital coaxial and digital optical it’s possible to have a USB DAC added, great for old computer systems and laptops.

Having heard some good things about these amps and seeing as it has an inbuilt DAC, for the price I was naturally curious and took the plunge. I’ve opted for the OPA627 model with USB in order to use with my netbook.


Zero 09 Version

Appearance, Accessories and Build.

I’m not going to lie, being an import from the far east I had my concerns about how cheap quality the components would be. The outside appearance is fantastic and really looks more professional than toylike, the volume knob feels sturdy as do the 3 smaller buttons. It’s not without fault though and I’ve found that almost every time I try and turn the amp on the power button doesn’t lock in and the amp turns off again, likewise the digital coaxial input on the back is wonky, I don’t think this would cause any issue though.

Accessory wise the box contained manuals in both Chinese and (badly) translated English; I could fathom the instructions after a few reads but to be honest I didn’t read them at first and had no issues, it’s mostly common sense. Also included is a mains cable - for Europe not for Britain - a 1m USB B type connection and a 1m optical S/PDIF connector.

Internally the construction is as good as most major amps I’ve seen the inside of (surprisingly a lot, I used to repair them), one of the things I especially like is that the op amps aren’t directly soldered to the board but instead have used a DIL (an IC holder, so to speak) which will allow easy swapping of op amps should you want to.


Zero's internals

Sound Quality.

Not a great deal of specs for this amp are available, what I have managed to find is that it supports 24bit audio at 192khz over optical or coaxial and 16bit audio at 48khz over USB. The signal to noise ratio is rated at 105db, bear in mind that anything over about 93db is marketing hype realistically as CDs are rated at 93db. Frequency response is rated at 20-30,000hz so will cover the average human hearing range. Now that’s covered I’ll just mention most of these values don’t really count for much as most amps are rated around the same or inflated to give a higher value (and thus more marketing potential), the hearing test is what’s most important.

There is a misconception around what the role of an amp is, most people assume it’s simply to amplify the volume however a good quality amp should be bringing out details in the audio and improving the general sound quality you hear, an example is a pair of headphones which have distorted bass, using an amp should pick the bass up and give it detail rather than just being a muddy mess, of course the headphones have to be capable of that just as much as the amp has to be capable of driving the headphones, it’s all a balancing act but one which can really pay off.

Normally being both a DAC and amp I’d review both parts separately, however the Zero only accepts digital inputs so this isn’t possible. The comparisons I’ll be using due to this are with a Xonar DG sound card which has a built in headphone amp and my Harman/Kardon AVR which has a headphone amplifier built in, albeit not as powerful as a dedicated headphone amp.

From what I can tell the USB and S/PDIF DACs are separate circuits therefore I’ll be reviewing each one separately, starting with the S/PDIF (AKA digital optical).

Turning on the amp, plugging in my DT770s and listening to Natalie Walker’s Urban Angel 2 things were immediately apparent to me; the lack of hiss and how smooth the sound is. Now when I say lack of hiss most people probably think it’s extremely quiet and you can’t hear it with music playing, what I actually mean is there is no audible hiss what so ever at the volumes I would listen to music, it becomes audible with no music playing at around the 1/2 volume mark but the ringing in your ears at this volume would be more apparent I’m sure. For the smooth sound all I can say is I can’t hear any distortion at all common with cheaper DACs, no spiking at certain frequencies and the audio is warm yet accurate, acoustics sound beautiful while bass is deep and clean.

Over time I’ve noticed the sound change subtly, high frequencies are becoming more apparent, not to the point of being harsh or over powering but I can hear more detail than initially. Soundstage which was initially not much larger or accurate than my H/K have over time expanded becoming more accurate and significantly more pleasing, admittedly on a number of occasions when I’ve not been paying attention I’ve forgotten I’m wearing headphones and thought my speakers are in fact playing (which is ridiculous considering they aren’t even connected to anything right now)! Just to clarify the amp doesn’t have Dolby Headphone or Binaural DSPs to create a wide sound stage or to emulate speakers and headphones still sound like headphones, but every so often...

Testing the Zero with my Beyers alone would be unfair so I decided to pit it against my Goldring DR150s which are renowned for being great headphones unamped but don’t really get much improvement from an amp, the improvement is there but subtle and in most cases won’t justify the extra cost. My Xonar DG gave minor improvements to the DR150s however my H/K 2550 didn’t do much to improve it at all, the Zero however had some success, again it’s subtle compared to the Beyers however it’s definitely there, the mids became more detailed and acoustics again had that lovely feeling, the bass and trebles improved slightly but was almost imperceptible, the soundstage also increased in size to a small degree. Sound was significantly cleaner than with the DG however I base this entirely on the DAC as the sound was cleaner with the H/K DAC too.

How does the USB fair I hear you ask? I went specifically for this model for use with my netbook which has poor onboard audio and no S/PDIF outputs. I should note that my netbook (Samsung NC10) has both XP and Ubuntu 10.10, but I basically only use Ubuntu. I was relieved to find that the USB DAC worked flawlessly in Ubuntu without having to do anything, it was all plug-n-play.

The USB DAC sounds very similar to the S/PDIF DAC with the exception of lesser bass response, this like with the rest of the amp might improve as it’s used however as of writing this review I’ve only used it for about an hour.

On the volume front I’d be surprised if anyone can have their Zero at full volume, with my relatively quiet DT770s I can only go as far as 1/4 volume, pushing to 3/8 begins to get to ear hurting levels and half is beyond me. With my DR150s I barely have to have the volume on at all.

There is one aspect of the Zero which I haven’t tested yet and that would be the preamp circuit, unfortunately I have way of testing this at the moment as I had to remove my speaker amp in order to use the Zero, in a few weeks when I’ve made space for my new speakers and my amp I’ll test the preamp capabilities and update.

Conclusion.

If you haven’t already guessed I’m absolutely stunned at how good the Zero is for the price, the DAC in my opinion is better than anything else I’ve heard and the amp brings out details I never knew existed and it just keeps getting better. However as with everything it does have its downsides, the ones which really stick out to me are the lack of analogue in which will be a deal breaker if you’re the type who uses old equipment and wanted to pair it up with a cheap headphone amp, or if you plan on using it with a portable device, it’s also not a neutral amp with the emphasis on the mids, bass and treble can seem a little recessed in comparison. The expanded soundstage might turn some people away too as one of the attractions of headphones is the immediacy they produce over speakers, while nothing like using Dolby Headphone the soundstage is larger than without and some of that immediacy is lost. If you know your headphones are renowned for improving with an amp you really should look into buying the Zero as for the price it really is a stunning piece of equipment.

Glossary: Burn In

2011-03-31T02:04:00.008+01:00

New headphones, speakers, amps and so on require use for around 100 hours in order to get the best sound quality, during this time sound characteristics can change, frequency range can increase, audio may become clearer.

To understand why burn in is required for headphones and speakers you need a basic understanding of how speakers work. All noise is vibration of the air around us and speakers use a cone to push the air to create this audio, the cone itself is attached to a large electromagnet which moves depending on the voltage put into it. Over time the electromagnet starts to move more freely and thus the audio changes, the easiest way to notice the change is in the high frequencies where there will be more detail, this is because the magnet can now move faster and more accurately.

Amps and anything with a circuit board inside will also benefit from burn in as over time capacitors change characteristics. I had some wonderful explanation here as to why this happened, however it requires knowledge of electronics, reactance and so on and I'm sure if you're really interested in the reasons there are better explanations out there than my own. Some people will also recommend opamps and other chips be burned in, I'm sceptical about this as I can't fathom what would change over time so I'll simply say your mileage may vary here.

Beyerdynamic DT770 Pro 250 Ohm

2011-03-24T00:04:00.008+00:00

Review: Beyerdynamic DT770 Pro 250 Ohm

Item: Headphones (Closed)

Price: £140 (click to buy from Amazon)

Beyerdynamic are a German audio equipment manufacturer whose headphones are regularly used in recording studios. Unlike a lot of cheaper headphone manufacturers Beyer sell replacement parts such as new cables, headbands and so on for their headphones. Coming in at £140 they are more expensive than your average headphones but how do they weigh up for their price?

Beyerdynamic DT770s in all their glory.

Appearance, Accessories, Build and Comfort.

As you can see very professional looking headphones, nothing about them looks cheap, and while not exactly a fashion accessory they hardly look ugly either.

The only thing to note inside the box other than the headphones themselves is a 3.5mm to 6.3mm jack, the jack itself is gold plated and feels of good quality and rather than plugging on the end of the headphone cable, the adapter is screwed into place. When attached it’s not possible to tell a 3.5mm jack lies beneath and gives that studio look to the headphones yet again, only a minor detail but it all makes an impression.

I mentioned before all parts are replaceable which had me worried that it would mean the components are of low quality and would need replacing regularly, well I can honestly say this isn’t the case! My initial reaction to holding these was how solid they feel, the headband is sturdy, ear cups are hinged onto a metal bracket and the back of the cups feel like they could take a few knocks. The cable is thick and strong so should prove nearly impossible to break, and being coiled gives you 3m of cable in a 1.5m package to make it perfectly suited to both portable devices and hi-fi.

Beauty is in the eye of the beholder and being study is all well and good but the thing that really matters with headphones is the sound quality, and coming in a close second, in my opinion anyway, is comfort. So before I go into how these sound I’ll talk a little about how these headphones feel when being worn.

Initially: With a padded headband and velour ear cups initially the headphones feel really comfortable; there is padding everywhere it matters. Over clamping, which seems to be more and more common, isn’t apparent here but they aren’t loose on my head either. Weight wise they aren’t the heaviest headphones on the market and do feel a bit weighted in-hand, when being worn seated or walking they don’t feel too out of place though. I’m not sure how long they’ll remain comfortable for though...

1 hour use: Currently no issue, all very comfortable and I’ve frequently forgot I’m wearing them.

5 hour use: Absolutely no fatigue normally associated with awkward headphones. For those who like to listen to music for extended periods this will be, excuse the pun, music to your ears...

Sound Quality.

So how do they sound? Well after plopping these on my head and putting on some Natalie Walker (as is my tradition when trying some new audio equipment) I had a stupid grin on my face which never really left. The first thing I noticed was how amazingly clear the audio was, it’s only when hearing something this clear that you realise how muffled other equipment is! It’s hard to explain but briefly the instruments sound more individual, more separate, there are details you’ve never heard before such as you can hear the strings being plucked, can hear instruments in the backing orchestra you’ve never noticed before and it all sounds much more open and realistic. The soundstage is pretty good too, I can clearly tell where most instruments are in my mind and nothing is coming from within in my head.

The frequency range is rated at 5 - 35,000hz, it should be noted that the average human hearing range is around 20-20,000hz making anything outside of this range largely useless. The bass is extremely rich and deep, the cans make use of an elliptical dish of sorts to reach those incredibly low frequencies, but the thing that sticks out most to me is how clean and clear the bass is, you can hear every detail in the low frequencies and will easily begin to notice sounds you’ve never heard before; extra rhythms in the low frequencies that don’t appear on other equipment. The mid range is detailed, vocals are clear and unobtrusive while the highs are concise and, you guessed it, clear. To my ears these are pretty neutral sounding headphones, the bass can be boomy the highs too bright sometimes and together they can occasionally overwhelm the mids however for me with the wide sound stage everything stands out and everything sounds even, I have no issues hearing quiet vocals in bass heavy music for example. One issue to note though is due to the treble sometimes audio can sound harsh and tracks which previously sounded fine now show recording artefacts both of which are attributed to recording quality or low bitrate audio.

Running the DT770s with an amp only increases the joy that these cans bring, the sound stage is wider again and more accurate still, the bass is still deep and rich but seems more distant and less overwhelming, the trebles less harsh and more descriptive, and, dare I say it, the sound clearer over all. Each instrument becomes a totally separate entity and nothing seems to be left out or left behind. As mentioned above the mids were never a problem and didn’t appear recessed to my ears, however amping gives the mids more precedence than before.

From both my Sansa Clip+ and iPhone 2G the volume is rather low even at the max end, something typical of more expensive headphones, it’s not by any means too low to hear but for anyone who likes a little oomph a portable amplifier such as the FiiO E5 or CMoy might be an idea. The headphones are still incredibly detailed considering what is driving them and I have absolutely no qualms in using them with my Clip+ around the house.

A neutral sound isn’t for everyone though; some people will prefer a more coloured sound signature and no doubt some will find the bass too powerful or the trebles to sharp, it’s something to bare in mind.

Isolation is fantastic in both respects, when worn I hear no ‘daily life’ droning noise what so ever and outside noises such as TV, conversation and so on are a distant muffle. With music on even at a low volume I’m deaf to the outside world. In respect of sound leakage as expected for closed cans very little sound can be heard when worn, at my average volume no sound can be heard and I have to pump the volume up to ear-hurting levels to hear much at all.

Conclusion.

For £140 these headphones seem a bargain and really do fit in both the studio and the home, they look and feel like a professional set of cans and the sound quality is exceptional. If you’ve £140 burning a hole in your pocket and just happen to be looking for some closed back headphones for extended use then honestly look no further! If you’re looking for something more portable or something coloured then there are better choices out there for the price range, but if clean and crisp sound is the most important and you want to hear music as it was intended to be heard without breaking the bank then you’d be hard pressed to find a better use for your cash.