Loud!Pack.Zip

Wiz Khalifa - Rolling Papers

2011-03-24T10:38:00.006-04:00

One of the most anticipated albums of 2011 hits the net, features from Curren$y, Too Short & Chevy. Download & tracklist after the jump.

Loud!

Tracklist

1. When I’m Gone
2. On My Level (feat. Too $hort)
3. Black And Yellow
4. Roll Up
5. Hopes & Dreams
6. Wake Up
7. The Race
8. Star Of The Show (feat. Chevy Woods)
9. No Sleep
10. Get Your Shit
11. Top Floor
12. Fly Solo
13. Rooftops (feat. Curren$y)
14. Cameras

Hulkshare Download [New Link]
Megaupload
Zshare
Hotfile
Depositfiles

Angry Birds Rio is Now Available for Download

2011-03-21T23:55:00.002-04:00

Loud!

Angry Birds Rio is now available on the App Store for download

What happens when everybody’s favourite fierce fowl get caged and shipped to Rio? They get very angry!

In Angry Birds Rio, the original Angry Birds are kidnapped and taken to the magical city of Rio de Janeiro, where they eventually escape their captors and set out to to save their friends, Blu and Jewel – two rare macaws and the stars of the upcoming Fox motion picture, Rio. Angry Birds Rio will pair the physics-based gameplay of the original game with unique twists based on the film.

Angry Birds Rio features:
- Two fantastic episodes with 60 exciting levels!
- Completely new achievements!
- Special Hidden fruits - discover them all!
- Put your Angry Birds skills to the ultimate test in a spectacular boss fight!

You can purchase Angry Birds Rio HD for iPad from the App Store for $2.99 and Angry Birds Rio for iPhone for $0.99.

WTF?! -This Gold iPad 2 Will Cost You £5,000,000

2011-03-21T23:49:00.002-04:00

Loud!

Stuart Hughes has announced the 'iPad 2 Gold History Edition' which features 12.5 cts of flawless diamonds and a £5,000,000 price tag.

Undoubtedly the world’s most unique gadget is the iPad 2 Gold History Edition. Encrusted with 12.5 cts of ‘I'F' Flawless diamonds, a magnificent total of 53 individually set sparkling gems dwell beautifully in solid 24ct Apple logo with rear section formed again in 24ct gold weighing an immense 2,000 grams. The unrivaled imagination towards the craftsmanship of the iPad is down to its main front frame which is made from the oldest rock the world has to offer in the form of Ammolite, sourced from Canada this stone is over 75 million years old. However to make this masterpiece even more individual, sections of a 65 million year old T-REX Dinosaur’s thigh bone was splintered and then shaved into the Ammolite , then finished off with ultimate jewel, as single cut 8.5ct flawless diamond inlaid in its own platinum surround with 12 outer flawless diamonds. A magnificent combination of top of the industry technology and unique thought were involved in creating this piece of History!

Material spec
16.5 ct diamonds & 8.5ct single diamond, 57 grams of T-REX bone, 750 grams of Ammolite stone and 2000 grams of solid 24ct Gold. This item is of a limited edition of only 2 units to be made.

Air Jordan Retro 3 - Pearlized Sample

2011-03-15T22:54:00.003-04:00

Loud!

With a quite a few popular styles of the Air Jordan III set to make a return in 2011, here's one colorway that surprisingly never made it passed the sample stage. At first glance many would think they are a variation of the silver anniversary Retro 3, or maybe even a custom. However upon closer inspection, they are quite different from the aforementioned.

A nice tumbled leather is seen working the entire upper, covered in a pearlized finish that shines from even a mile away. An off-white shade is also apart of the look, working the classic elephant print and backtabs. With not much color or life to them, could this be an early sign of things to come with the Air Jordan Retro 3 Premio?

Not much is known about this latest sample, be sure to keep it locked to Sole Collector for the latest scoop and a closer look.

Air Jordan II Max - White/Black-Varsity Red - New Detailed Images

2011-03-15T22:19:00.002-04:00

Loud!

For the second time today, we have new images of the upcoming Air Jordan II Max. After the Jordan Brand employed 360 Max Air cushioning for the first time last year with the Take Flight, they follow up in a big way, using it to aid the ride of the Air Jordan II. This pair combines the looks of the original Jordan II colorways, but is better equipped for modern performance. In addition to the 360-Air unit, the shoe features an open-hole mesh tongue and updated traction pattern on the outsole.

Considering that there's an actual performance aspect to this update, would you like to see other Jordan Models receive a "Max" makeover? Whether we like it or not, it's safe to assume this won't be the last one we see.

Color: White/Black-Varsity Red
Style: 455616-100

Sneaker Watch: Kobe & The Lakers Ready For A Run

2011-03-15T22:06:00.002-04:00

Loud!

Despite all the off-court antics and entertainment that is synonymous with the Los Angeles Lakers during this time of year, this year is shaping up to be just like the last for the “Lake Show.” After the usual bickering, questioning, and poor performance, Kobe and the Lakers moved to 10-1 since the All-Star break with a victory of the Orlando Magic. Playing through a sprained ankle, Kobe was more animated than usual on Tuesday. He put in 16 points but his presence on the floor showed his leadership and was apparently motivating to the rest of the team as Gasol, Bynum, Fisher and Odom all scored in double figures.

The only other team in the league that has been as hot as the Lakers since the All-Star break is the Chicago Bulls. With Derrick Rose leading the way, Chicago is tied for the best record in the East after the Celtics lost to the Nets on Tuesday.

With both teams playing at a level the rest of the league can’t seem to maintain, a rematch of the 1991 NBA Finals seems like a pretty good possibility. Back then it was MJ and the Bulls taking the torch from older, Magic Johnson led, Lakers team. Could 2011, 20 years later prove to be the “changing of the guard” for Chicago and Derrick Rose?

It would make a nice story, and a nice anniversary gift for Bulls fans.

Apple News | iPhone Used to Hack Times Square Video Billboards? [Video]

2011-03-15T21:46:00.001-04:00

Loud!

A new YouTube video demonstrates a hack which purportedly takes over the video display of Times Square's massive screens using an iPhone. CBS posted the story saying, "First off I'm going to state that I do not know if this is in fact real or fake. My gut is telling me it has to be fake... but if it's real, I'm so going to buy one!"

Here's how the poster describes the hack...

the way it works is pretty simple: plug in my transmitter into the iphone 4 and play back any video clip. you can play it through the ipod feature or through the camera roll. the transmitter instantly sends the video signal to the video repeater and the video repeater overrides any video screen that it's being held next to. it doesn't matter what shape or size the hacked screen is because the hack video will simply keep its correct dimensions and the rest of the hacked space will stay black.

i chose times square for my demo because it has lots of video screens to try it on. it is also one of the most monitored and secured areas in new york city and that made it that much more fun :). you can see in my video that the repeater is pretty powerful but the signal is not very stable yet. i'm working on that. i will post a new video later this week explaining how i made this prototype.

Even if the hack is fake, the video is pretty impressive.

Warning: Jailbreakers and Unlockers Should Wait Before Updating to iOS 4.3

2011-03-09T21:44:00.002-05:00

Loud!

As usual those looking to jailbreak or unlock their devices should wait before updating to iOS 4.3.

This warning is especially important for those looking to unlock 01.59 on iOS 4.3 because the unlock for newer basebands is taking longer than expected.

Ultrasn0w unlockers should know the drill! Don't let iTunes trick you into installing today's 4.3 iOS. Just say no!

Sorry, there's no news on the i4 unlock for those who lost 01.59 (or never had it). It's taking longer than we wanted :(

MuscleNerd also notes that there are many possible sources for a untethered iOS 4.3 jailbreak. i0n1c, Comex, Charlie Miller, and possibly others.

BigBoss has also warned against performing an "unofficial" jailbreak due to issues with Apple’s implementation of address space layout randomization that messes up MobileSubstrate.

We'll keep you up to date with news on the jailbreak and unlock front as it becomes available.

1962 Impala

2011-03-09T17:17:00.004-05:00

Loud!

Nike Dunk High AC Vintage QS Available

2011-03-09T17:13:00.002-05:00

Loud!

My Shoes, My Story : The Original "Steel Grey" Air Jordan X

2011-03-09T17:01:00.003-05:00

Loud!

Originally published October 15, 2008

I wrote this a few years back. Here I picked a shoe that has a special meaning to me. So without further ado, here is my story....

Ah yes, the original Air Jordan X. Originally released in 1994. Has it really been that long? Seems like only yesterday that I put these on my feet for the first time. These indeed were my first pair of Air Jordans, every kid's dream. The story behind them is one I surely will never forget.

It began in the summer of 1997. For the past few summers a few of my friends and I would goto a local park during the week where they had organized activities for kids where they'd play sports like dodgeball, kickball and such. Not to mention, games like arts & crafts, board games, etc. It was basically a place where parents could dump off their kids for a few hours and let them play with other kids under adult supervision while they were at work.

I had just finished seventh grade, and as the summer began so did the trips to the park. I had become friends with a kid named Mike who lived in Florida but came up to visit his grandparents every summer. We became good friends and for a few years would hang out religiously all summer long. Mike came from a more fortunate family then me so needless to say I always envied him. We both played basketball but aside from our height difference (I was only 5'4 at the time), there were other things that set us apart on the court.

The most noticable difference was footwear. He I remember was wearing the original Jumpman Team I in the white/black colorway. I on the other hand was still wearing the Fila Grant Hill III's in the white/black colorway. I always wanted a pair of Jordans but my parents could never afford to get me a pair no matter how hard I tried to pursuade them. Now the Grant Hill's weren't cheap, and I think they were around $80. Back then, $80 for a pair of sneakers that would be worn to the ground was a lot of money to my family.

One day after playing some ball at Mike's grandparent's house as the summer was winding down, Mike asked me what size shoe I wore. I was a size 6 (at least for a few more months), even though my height was slowly increasing my feet had not quite caught up (they would in the future as I now wear a sz. 12 and am only 5'9ish). He was I believe a size 10 at the time, not that it mattered. He then told me to wait outside for a second as he had to go talk to his grandma. I waited, and then he came back out and said come inside.

I followed where he took me into the basement. His grandma was already down there, and as I made it to the last step I saw them. I will never forget it, she was holding a pair of brand new original Air Jordan X's in the white/black/light steel grey colorway. Mike said that his grandparents bought him them when they came out and held them for him until he came up that following summer. Problem was that when he got there they didn't fit, so he never wore them and they had remained untouched in his basement since then, unfortunately without a box.

The next words out his mouth I will never forget, as he asked, "Do you want them?" Inside I was overwhelmed with excitement and without hesitation, I said, "I would love to have them!" Next thing I knew I had gotten my first pair of Air Jordans ever! I couldn't wait to tell my parents, and I later left Mike's and went home while keeping this all a secret (no matter how hard that was) until I got home. As soon as I got in the door I raced up the stairs and told my mother the exciting news. She was as happy for me as I was, and so was my father.

I put them on and wore them around the house calling a few people to continue to spread the excitement for one of the greatest moments in my life. Growing up I always wanted a pair of Air Jordans and could never get a pair, until now. Friends had them, others had them and now you could add me to the list. I was finally able to put all the naysayers to rest. All my life people always told me I would never have a pair of Jordans, saying I was too poor, etc, etc. So you know I couldn't wait to rub it in everyone's faces!

A few days later my best friend came back from visiting his family in Puerto Rico and I went to his house wearing MY Air Jordans. Another friend of ours lived a street over, and he was one of the kids that always said I would never get a pair. So we walked to his house, I rang the doorbell, which he answered, and I said, "You said I'd never have a pair of Jordans huh? Well look at my feet!" He stood there speechless. My work was done for now, and I couldn't wait til school began to wear them and show off to all the others who doubted me.

As school began and soon after basketball season started, I wore them for a few games until my feet began to hurt and I went with my mother to get a new pair. Little did I know the reason they were hurting was because my foot was now a size 10 and I was trying to cram my foot into a size 6 everyday - ouch! So it was time to retire my J's and go back to my normal routine of wearing Grant Hill's shoes. This thankfully was my last time I ever had to wear a pair of Filas, and when I entered high school I was back to wearing Jordans and that trend obviously never stopped.

I kept these Jordans as I said to my little brother than when he was a size 6 he could wear them and they would be his first pair of Air Jordans as well. After a few years this came true and it's truly a great memory to have knowing that both myself and my younger brother wore the same pair of Air Jordan X's and they were our first pair of J's as well. After he was done with them I got them back and to this day still have them and will never get rid of them.

Yes they are completely worn, some of the elastic straps are gone and only a few of the accomplishments remain on the sole and the laces are also missing. But that doesn't mean they lost any of their history and the memories I had in them. They forever will be my first pair of Air Jordans and Mike, wherever you are, thank you for giving them to me.

Eastbay Photo of the Week: The Air Jordan 2011 Family

2011-03-09T16:58:00.002-05:00

Loud!

Most of us got into sneakers somewhere along the line of Jordan shoes that is now over 25 years in age. Like the shoes, some have made additions to their families over those years and blessed the world with the next generation of sneakerheads. The Air Jordan 2011 is this subject of this week’s Eastbay Photo of the Week and it captures the age range of sneakers both young, and young-at-heart, in a way that really needs no words.

Video Taken With the iPad 2 Back Camera

2011-03-09T16:48:00.004-05:00

Loud!

Check out these video clips taken with the iPad 2's back camera. Apple says this camera takes HD (720p) video at up to 30 frames per second with audio.

Macity notes that the quality of the footage below isn't perfect because it was sent by email and uploaded to YouTube.

As mentioned in the first movie the quality of the shot is not 'exceptional because there we are sent by mail and the final resolution is more than halved and some artifacts are introduced next with uploading to YouTube.

64GB iPhone 4 'Engineering Prototype' Hands On [Video]

2011-03-09T16:41:00.008-05:00

Loud!

M.I.C. Gadget has posted hands on video with a 64GB iPhone 4 'engineering prototype' obtained from the grey market in Hong Kong.

The next iPhone? We are not sure, but we’ve just got our hands on an engineered prototype of iPhone 4, with 64 GB storage capacity. We tested it, and it is the real thing, no jokes here. On the back of the device, it has “XXGB” marking, representing the unit as potential Apple prototypes. However, we found out that the device is very similar to the lost iPhone 4 prototype bought by Gizmodo. We have a video and some photos for you to take a clearer look at it.

Apple Releases iOS 4.3 for iPhone, iPad, iPod Touch, AppleTV

2011-03-09T16:34:00.002-05:00

Loud!

Apple has released iOS 4.3, its latest operating system update for the iPhone, iPad, and iPod touch.

This update contains new features and improvements, including the following:
● Personal Hotspot
- Share iPhone 4 cellular data connection with up to 5 devices (comination of up to 3 Wi-Fi, 3 Bluetooth, and 1 USB)
● iTunes Home Sharing
- Play music, movies and TV shows from a shared iTunes library on a Mac or PC (requires iTunes 10.2)
● New AirPlay Features
- Play videos from the Photos app including the Camera Roll album, iTunes previews, enabled third-party apps, and websites on Apple TV.
● Faster Safari Performance with Apple Nitro JavaScript engine
● HD Video Out using the Apple Digital AV Adapter
- View 720p HD videos from the Videos app, iPod app, Photos, YouTube, Safari, Keynote, and enabled third-party apps on an HDMI display
● Ping Features
- Push notifications for comments and follow requests
- Posts and Like songs directly from the Now Playing screen
- Parental contols
● New Settings
- Messages setting for number of times to repeat an alert
- iPad side switch settings to lock screen rotation or mute audio notifications and sound effects
● Single tap conference call dialing with a pause to send a passcode
● Bug Fixes

Products compatible with the software update:
● iPhone 4 (GSM model)
● iPhone 3GS
● iPad
● iPod touch (4th generation)
● iPod touch (3rd generation)

You can learn more about iOS 4.3 here.

You can find download links here:
● iPhone
● iPad
● iPod touch
● AppleTV

Apple to Release iOS 4.3 Today? [Update]

2011-03-09T16:30:00.003-05:00

Loud!

A new report from BGR predicts that Apple will release iOS 4.3 at 10:00 AM PST / 1:00 PM EST today.

There has been a lot of talk surrounding Apple’s personal hotspot feature, specifically it’s capability of only supporting 3 wireless connections (as opposed to 5 like many other devices). Well, we have been told it’s all left to the carrier to decide. If a carrier requests it, five devices will be supported, but by default, it’s three.

Oh, and we’ve also been told iOS 4.3 will be available for download publicly at 10AM PT today. Fire up iTunes and get your update trigger-finger ready!

Apple publicly announced that it will release iOS 4.3 on March 11th in a press release. "iOS 4.3 will be available to iPad, iPhone and iPod touch users as a free software update on Friday, March 11." However, BGR has correctly predicted release times in the past.

Update:
The Loop is reporting that the update may actually come tomorrow instead.

The speculation of iOS coming early seems to be solid, it’s just the day that’s off. If I were sitting waiting for iOS 4.3 to hit, I’d be ready tomorrow.

Apple to Begin White iPhone Production This Month, Start Shipping Next Month?

2011-03-09T16:13:00.003-05:00

Loud!

Manufacturers will initiate production of the GSM-based iPhone 4 version in white enclosures and begin dispatching them to Apple ahead of general availability planned for next month, Concord Securities Analyst Ming-Chi Kuo told AppleInsider. Apple has made changes the "film material to solve the full-lamination problem that [was] the reason why white iPhones [were] delayed," he added. The handset was first scheduled to debut last June. Kuo did not provide a timeframe for a white CDMA-based iPhone.

With the introduction of the CDMA iPhone, iOS 4.3 set to become available this week and an anticipated launch of the white iPhone 4, Kuo sees Apple selling a record 18 million iPhones in the first quarter of calendar 2010. That would easily best the 16.2 million phones Apple sold in the holiday sales period to end 2010.

More evidence that Apple has solved its white paint mixture woes came last week with the unveiling of the iPad 2. The new touchscreen tablet will come in both black and white, and Apple Chief Executive Steve Jobs said both models will ship on the March 11 launch date -- a statement that drew laughter from the audience at the Yerba Buena Center for the Arts in San Francisco.

AppleInsider reported in January that Apple had made strides in developing a new material that would allow it to successfully manufacture a white iPhone 4 that meets the company's high level of standards. Using earlier painting methods, Apple's attempts to manufacture the white iPhone 4 apparently resulted in a "huge" number of defective handsets.

Unable to produce the white iPhone 4 in 2010, Apple allegedly partnered with a Japanese company that crafted a new paint material. The new material apparently allows for greater control and precision in setting the thickness of the paint layer.

Tity Boi - Gasolean

2011-03-02T08:34:00.002-05:00

Loud!

Nike SB Dunk High QS - "Statue of Liberty"

2011-02-19T12:38:00.003-05:00

Loud!

Images of the already-popular "Statue of Liberty" SB Dunk High continue to surface. The shoe sports a seagrass green leather upper with a lighter mint green used for the tongue and laces. Providing a little vintage appeal is sail, which is used for the inner liner and sole. However, it's what lies beneath the surface that really makes this a special release.

When the top layer is scratched, a bronze colored under layer is revealed, symbolic of the oxidized defects of the actual Statue of Liberty. Other details include a Lady Liberty tongue badge and graphic work on the insoles. Look for these to hit your local skate shops in March.

Color: Seagrass/Seagrass
Style: 313171-302

Rick Ross "NBA All-Star Los Angeles" 2011 Blog 1! Rozay Cops Weed From A Medical Marijuana Dispensary, Parties With Kevin Durant, Andre Johnson, Wale

2011-02-18T22:53:00.001-05:00

Loud!

Funny: Eddie Griffin Wanting To Smash Michelle Obama, NBA All Star Weekend & More! (Lopez Tonight)

2011-02-18T14:18:00.002-05:00

Loud!

Air Jordan 2011 & Retro 3 Headphone Packs

2011-02-18T14:01:00.002-05:00

Loud!

Last summer, the Jordan Brand teamed up with audio equipment manufacturer and customizer Skullcandy on two "For the Love of the Game" Pack releases. The two sides find themselves paired up again this year, with custom "Aviator" headphone sets being released this weekend for the All-Star festivities and the official launch of the Air Jordan 2011.

The first Aviator set being released is for the brand new Jordan 2011. The headphones feature one blue ear and one red ear, which is inspired by the interchangeable "Quick" and "Explosive" midsoles that come equipped with the shoes. The headphones will be packaged with a pair of the new MJ signature shoe.

Also being released is the Air Jordan Retro 3 Aviators, which salute the recently released "Cement" Jordan 3. As you'd expect, the headphone feature the elephant print that you'll find on the toe and heel rands of the aforementioned Air Jordan.

Priced at $500, these sets will be exclusively at the Westfield Culver City Mall Footaction location this Saturday. Doors open at 10:00 a.m. PST.

Air Jordan Retro 5 - Light Graphite/White-Wolf Grey - New Images

2011-02-18T13:47:00.003-05:00

Loud!

Like just about any grey-based Air Jordan sneaker, this Retro 5 was initially assigned a "Cool Grey" nickname, but actually makes use of a darker light graphite nubuck upper. Wolf grey and white compliment the look at various points, including the tongue and a contrast stitch throughout. The midsole is also done in light graphite and is accented by a speckled wolf grey "teeth" design." Adding the finishing touch is a translucent rubber outsole below.

This pair is expected to release on May 14th at select Jordan retailers. Stick with Sole Collector for any updates.

Color: Light Graphite/White-Wolf Grey
Style: 136027-005

Subwoofer Enclosures - Box Basics Part 2

2011-02-18T11:52:00.002-05:00

Loud!

Have you ever wondered what it takes to be a big time competitor in the SPL arena, posting the big numbers—you know, the ear-shattering 170-plus decibels? If you know something about physics, you may think you have it figured out. You would know that rapidly compressing and rarifying the air can change the pressure within an airtight environment, in this case the cab of the vehicle. And if you were so inclined, you would likely apply this knowledge in SPL competitions by searching for the "golden subwoofer" with high power handling potential and the longest excursion (so that as much air as possible could be moved). Once you found the "golden subwoofer" you would measure the vehicle to see just how many of these puppies you could stuff into the interior. And, since you want to compress and rarify the air, it would make sense to have a sealed chamber, where the front and rear wave of the speaker could not interact. All the while you would want to minimize the volume of the chamber (cab of the vehicle) so there would be less air to move. In the end, you wind up with a sealed enclosure.

Stepping into the SPL lanes will cause most physicists to become confused. Immediately, they'll ask, "Where are all of the sealed enclosures?" You see, the majority of warped and extreme competitors taking top honors in SPL competitions today use ported enclosures, not sealed. Why? I think it is safe to say that many of these competitors don't actually know themselves, they just learn from trial and error. Cut and try.

So where does the answer to high SPL lie? The physicist is actually correct in theory to recommend a sealed enclosure. However, there is one small problem: subwoofers. Current subwoofer designs cannot move enough air due to excursion limitations. On the other hand, ported enclosures are slightly less dependent on excursion. So how are they producing such high output? There are a couple of reasons for this. The first is the design of the enclosure. Ported enclosures can be tailored to have a large gain in response over a small bandwidth by simple alterations of the enclosure volume and port dimensions. These simple alterations can produce a peak from 10 to 15dB, raising the sensitivity of a normal speaker within the small bandwidth over the 100dB mark. The second reason for such high output is the alignment of the front and rear sound waves based on a specific vehicle. This is the portion of the design that eludes most competitors.

SPL Waveform
In Box Basics Part 1, I covered the differences amongst a variety of today's popular enclosure styles. One particular enclosure, the ported, is the basis for the SPL waveform theory I am about to go over. But, before I get into thick of things, I would like to recap the design principles of a ported enclosure.

Ported enclosures are distinguished by a vent or duct in the structure. This vent allows the rear sound wave of the woofer to interact with the front sound wave. The coupling of a vent to the air inside the enclosure reinforces the low-frequency response of the subwoofer system and can greatly increase the efficiency. By changing either the length or surface area of the port, the resistance to motion of the column of air within the port changes its resonant characteristics, thus causing the tuning frequency of the enclosure to change.

These traits are very important to the design of an SPL enclosure. However, the key element of this design is the rear sound wave interaction, better yet, the coupling with the front wave of the speaker. These two waveforms are naturally out of phase with each other (figure 1) and can cancel one another out in a free-air setting. The idea is to get the rear sound wave in phase with the front sound wave. This can be accomplished by the design of the enclosure and will yield a significant increase in output that is ideal for the SPL lanes (figure 2).

Unlike a normal ported enclosure that is built for a broad range of frequencies, an SPL enclosure is designed to be more "frequency specific". In other words, sound quality is not a priority in the design of these earth-shaking mutants. Rather, the concentration will be to produce a one-hit (frequency) wonder. This will likely require a substantially sized enclosure and the port or vent to be commonly larger than the Sd (cone area) of the subwoofer.

The Design Process
The first step in designing an SPL enclosure is finding the frequency that will work best in your vehicle. But how do you know what is the correct frequency to use? This is not as complicated as it may seem.

A single frequency sound wave will take the form of a sine wave. This sound wave can be measured or equated by using a simple formula. Sound waves are normally measured in feet, but since we are working in the small confinements of an automobile, it will be more practical to show this in inches. This means that you must first start by converting the speed of sound, 1130 feet/second, into inches. This can be accomplished by simply multiplying 1130 x 12 for a result of 13560 inches/second (figure 3).

Now let's start the design of the enclosure within the vehicle. Using the rules for dB Drag Racing (Super Street and Extreme competition), we have the following: "All loudspeaker enclosures, and/or baffle boards, with the exception of those mounted in the kick panels or doors, shall be located behind an imaginary plane that stretches from the trailing edge of the driver's door to the trailing edge of the passenger door". With this in mind, placement of the enclosure will likely be positioned slightly behind the door jam, as shown in figure 2.

In figure 2, there are four lines marked A, B, C, and D. Since line A is technically in-phase, we will start with this. Line A relates to the measurement from the speaker cone to the point of reference at the dash where the microphone is placed during competition. Let's use a nice round number for this length, say 50". Knowing this we can now calculate the frequency, employing the equation in figure 4a. At 50", the equation tells us that the full waveform at the dash will be 271Hz. Unfortunately, this will not fly in dB Drag Racing where the rules state that the frequency used in the competition must be 80Hz or below. So how do we get the frequency from 271Hz below the 80Hz mark? If we break down a sound wave into four sections, 90/180/270/360 degrees, it is possible to lower our peak frequency. In this case using a 1/4 of the waveform, 90 degrees, our peak frequency will lower to a very usable 68Hz (see figure 4b). Perfect!

Now that we know that 68Hz is going to be our peak frequency, it is time to hit the computer for our enclosure volume and port dimensions. There are several enclosure programs available that can perform this task. LEAP by LinearX is far superior to most because it takes into consideration the behavior of a loudspeaker at high power levels (see p. 72). But others such as Termpro and BassBox Pro do an excellent job as well. The goal of designing the enclosure is to create the loudest peak possible near the 1/4 wave frequency (see figure 5). Be prepared, the design of the enclosure may take some time; this is basically trial and error to find the correct volume, and an estimated port area and length.

Once the enclosure volume and port are decided, the actual design must take place, the most integral part of the process; so we are certainly not out of the woods yet. Figure 6 displays both the front and rear wave and how they should form in the vehicle. Reverting back to figure 1 for a second, the front of speaker is noted as 0 degrees and the rear is 180 degrees. This is the same as in Figure 6 (noted by the yellow and green lines). The idea is to align the rear wave with the front wave. This means that the front wave starts at 0 degrees and reaches the reference point at the dash at 90 degrees. On the flipside, the rear wave of the speaker starts at 180 degrees and reaches the dash in-phase with the front wave at 90 degrees. This means that the rear wave of the speaker must be exactly three times the length of the front. In equation form: 3A = B + C + D (refer to figure 2).

There is a good chance that you may be using more than one subwoofer in your competition vehicle, so there is one other issue you need to consider. By now you understand how to control the sound waves produced by the subwoofer. When multiple subs are used, each needs to be on the same wavelength, so to speak (playing the same frequency). This means that each sub needs to be the same distance from the microphone as the next. This also means that the rear sound wave has to be the same distance. Keep in mind that the enclosure volume and port must stay the same per subwoofer, but the dimensions of the enclosure may change so that the rear wave remains in-phase with the front. Now you are set to start building the enclosure -- but be sure to leave yourself room for adjustments, mainly with the port length. Computer programs will give you a good base to work off of, but it's not always exact.

There are several other aspects to the design of an SPL competition vehicle, such as altering the interior volume and strengthening the enclosure. The interior volume should generally be more than or equal to that of the enclosure; otherwise the peak frequency may change and alter the output of your design. The strength of the enclosure matters greatly to reduce harmful resonance. Any structural support should be done on the outside of the enclosure to assure that there are no additional reflective surfaces in the enclosure that may add cancellation.

Hopefully I have provided you with an understanding of what is happening in some of these competing enclosures on wheels. Controlling the waveform inside a vehicle can have substantial benefits in terms of SPL, and coupling the rear wave of the speaker with that of the front wave substantially increases volume, which is advantageous when you are reaching for high scores.

Temperature vs. Sound
The speed of sound can vary depending on the temperature of the air. As an example, at 60 degrees (F), the quarter wave of a 50Hz sound wave will form a complete wave in 67 inches, whereas the same frequency (50Hz) needs 69.13 inches at 90 degrees (F). A drastic change in temperature may vary the peak frequency in your vehicle by 1-3Hz. —Casey Thorson

Subwoofer Enclosures - Box Basics Part 1

2011-02-18T11:30:00.003-05:00

Loud!

Today's market is inundated with woofers that offer respectable performance and great cosmetics at affordable prices. The variety is terrific for consumers, but the sheer quantity makes it difficult to pick a speaker. Things are then further complicated by the issue of enclosure style. This is one of the more controversial topics in car audio. Everyone has an opinion as to which kind of enclosure is best, but some people like to think that there is only one truly superior box design. In fact, there are several styles to choose from and each one has its upside. In the end, the issue boils down to what you want to do and the kind of music you listen to. The focus of the following tutorial is to elucidate the popular enclosure designs, exploring the various pros and cons and explaining the trade-offs involved in a given enclosure design. In addition, we'll provide a brief history of "making boxes for speakers" (a simple way to describe soemthing that has become somewhat complex).

Everyone wants a clear-cut response to the following question: "What speaker enclosure produces the best sub-bass performance?" I'm asked that a lot; and to this day I have not arrived at any kind of absolute answer. While I have developed my own opinions on the various styles of enclosures, I would have to say that for the most part the good and bad aspects of the different styles tend to cancel each other out in the end.

Like I said, this is perhaps the most controversial area of car audio. Of course, that's because you have competing methods or technologies at work and no single enclosure design that provides users with all the advantages the various boxes offer with none of the disadvantages. Many enthusiasts will swear that sealed enclosures producce the best performance, while others are equally adamant about the benefits of ported and bandpass designs. Most of these people are well-intentioned in recommending enclosures that they have had success with, but anyone who says that a given enclosure type is superior in every way is always wrong.

Infinite Baffle

Infinite baffles (IB), often termed "free air", are possibly the simplest enclosures to build (and a great way to conserve space). This design is defined as an enclosure that contains a greater volume of air than the Vas (the volume of air having the same compliance as the driver's suspension) of the speaker. Applying an infinite baffle system in an automobile is relatively easy. The concept of an IB is to isolate the sound wave produced by the front of the speaker from the back wave. This normally involves mounting the speaker(s) on a board that seals off just behind the rear seat while using the trunk of the vehicle as the enclosure. When all is said and done, an IB enclosure is truly quite large.

There are many trade-offs when working with IB enclosures. Sure, using IB saves space, especially in trunks of smaller cars. However, there are some lossed to be noted. The most prominent of these is efficiency. Without a solid structure built around the woofer, it is difficult to reinforce the sound. Trunk interiors are filled with flimsy panels, thin sheet metal and usually a measly spare tire—none too pleasing for sound reproduction. This same issue holds value with the speaker's power handling. As much as 50% of the nominal power handling of a woofer can be lost when placed in an IB. Another anomaly that plagues IB enclosures is the tendecny to lose control of cone movement when played below the Fs (resonance frequency of the driver), much like ported systems when played below the tuning frequency. For this reason, it may be desirable to utilize a subsonic filter below the Fs of the speaker.

When purchasing IB speakers, keep in mind the following parameters to assure that the speaker is right for the application. The first is the Qts (the total resistance of the driver at its resonance). Speakers with a Qts greater than 0.6 typically work well in an IB environment. The second is the Vas, which should be smaller than the total volume of the environment the speaker(s) are being placed in.

Infinite Baffle:
Good: minimal space consumption; generally easy to build.
Bad: poor efficiency; sometimes difficult to isolate front and back wave; limited cone control below speaker Fs.

Sealed Enclosure

Sealed enclosures have stood the test of time and have grown in popularity through the years. This design was first patented by Harry Olson in 1949 and then exploited by Acoustic Research in the early 1950s. Today, sealed enclosures (aka: acoustic suspension) are the most commonly used by car audio enthusiasts around the world.

Industry aficionados often associate sealed enclosures with “sound quality”. It is generally accepted that the transient response exhibited by these enclosures is superior to other box designs when they are built to the optimum size required by a particular speaker. Much of this can be contributed to the “acoustic-spring” that adds to the restoring force of the speaker. The acoustic-spring is a reaction from the air trapped within the enclosure that compresses or rarefies as the cone moves back and forth. This is greatly affected by the distance that the cone of the subwoofer moves. The longer the stroke of the woofer, the greater the force exerted by the acoustic-spring in the opposite direction.

Power handling of a sealed system is a trait directly related to the acoustic-spring. It is the increasing load on the cone of the woofer that maintains control as the excursion increases, thus allowing for more power to be applied to the speaker. But power handling can be greatly affected by the size, or tuning if you will, of the enclosure. Larger enclosures have less of a limiting factor on the speaker cone, allowing the woofer to play lower with a more gradual role off while compromising power handling and some efficiency. On the other hand, decreasing the size of the enclosure, the acoustic-spring exerts more control over the cone motion with a trade-off in low frequency response. While this may increase power handling, the system will not play as low and often produce a rise, or bump, in the frequency response.

The size of the enclosure also determines the shape of the response. This is stated as the “Qtc.” To be specific, Qtc is the value of damping provided of a speaker system. To give an example, a sealed system of optimum performance has a Qtc of .707. What this means is that the frequency response of the subwoofer will roll off at a -10.5dB/octave slope in the lower frequencies. Figures 1 and 2 give examples of different Qtc values and the shape of their response.

Altering the Qtc is not only dependent on the size of the speaker enclosure. Another way to change this is by adding "enclosure fill." Using fill can be an invaluable tool to alter box response in order to achieve certain parameters and Qtc value that may be difficult to achieve due to size constraints within the vehicle. Dacron, polyfill, fiberglass and acoustic foam are among the most commonly used enclosure fills. Adding these materials within an enclosure can effectively reduce the Qtc, reduce standing waves, and lower the resonance of the system. As well, proper selection of the amount, type of material, and the location of the material within the enclosure can also increase efficiency by up to 15%.

Although not every woofer works well in a sealed box, there are many competent speakers designed for this type of application. Most will operate in a variety of enclosure volumes that can produce good high-fidelity sound, and most consist of a simple design and easy construction. Perfect for the do-it-yourselfer.

Sealed Enclosure:
Good: easy to build; small enclosures; high power handling; excellent damping and transient response.
Bad: sub-par efficiency.

Ported Enclosures

The reputation of ported enclosures has not been one of quality sound Rather, they are often perceived as being sloppy and generally not very accurate. This common misconception is likely a product of a poorly designed or an improperly ported enclosure. It is not uncommon for ported (vented) enclosures to have better transient response than underdamped sealed enclosures with a high Qtc.

As odd as it may sound, ported enclosures have been around longer than the simpler sealed box. The patent on this design was first issued to A.C. Thuras of Bell Labs back in 1932. His work contributed to basic theory of the design, describing in detail the interaction between the driver and vent. It was not until 1961 that A.N. Thiele published a landmark paper that was later(1973) refined by R.H. Small who defined the behavior of a speaker, thus allowing for ported enclosures to be perfected. Their contribution is well known as Theile-Small parameters and most commonly related to ported speaker systems.

Ported enclosures are often referred to by many names such as bass reflex, tuned, or more commonly, vented. What distinguishes a ported enclosure from that of a sealed is the port or duct that allows the back wave to interact with the front wave. The coupling of a port to the air inside the enclosure reinforces the low-frequency response the subwoofer system. By changing either the length or surface area of the port, the resistance to motion of the column of air within the port changes its resonant characteristics, thus causing the tuning frequency of the enclosure to change.

In a ported enclosure, there are three main factors that have to be considered: the parameters of the speaker being used, the volume of air in the enclosure and the size (diameter and length) of the port Proper integration of these three factors will have a positive effect on the output of a ported system. The primary goal of integrating these three factors is to delay the rear output wave of the speaker so that as it comes out of the port it is relatively in phase with the wave produced by the front of the speaker. The result is a gain in efficiency of about 3dB compared to a sealed system using the same woofer. It is this low-frequency reinforcement that is one of the big advantages of a well-designed ported system. Another big advantage is that near the tuning frequency, almost all output is from the vent so come movement is controlled to the point of almost no movement. That results in lower distortion at higher volume levels in the frequency range controlled by the port. But not everything is perfect with ported enclosures. They suffer from one main drawback: the response of the speaker below the tuning frequency. The speaker no longer has the restoring force of the air in the enclosure, and therefore the cone acts as though it were not enclosed at all. This can lead to serious damage to the speaker itself and leave you stranded without sound.

The laws managing the performance and proper design of ported speaker systems are considerably more complex than those for sealed enclosures. It is very easy to screw up a ported system, so make it a good practice to follow the manufacturer’ advice, or the advice of an experienced system designer. Guessing at the port dimensions will likely create a bad sounding enclosure and may also damage your expensive speaker.

Ported Enclosure:
Good: good overall efficiency; enhanced low frequency output; relatively low distortion (above tuning frequency).
Bad: loss of woofer control below tuning frequency; large enclosure sizes.

Bandpass Enclosures

By now, most car audio enthusiasts are probably familiar with bandpass enclosures. Starting in the early '90s they became the rage of the car audio world. But bandpass enclosures are far from being a new design concept. Even for the '90s. It may surprise some people to know that these designs have been around since the 1930s. The original patent for a single reflex bandpass was filed in '34 by Andre d'Alton. Just over five decades later, Bose was granted a patent on dual reflex bandpass enclosures. A few years after that, Jean Margerand republished the methodology of two French designers, Augris and Santens. It was their hand-calculator design system for single reflex bandpass speakers that is likely responsible for the eruption of popularity amongst manufacturers as well as consumers. In the last ten years, considerable progress has been made in defining the behavior of these speaker systems in both home and car audio.

So where did the term "bandpass" derive from? The terms refers to the fact that the enclosure will only allow a certain frequency range (band) to play (pass) into the listening environment without the aid of a crossover. In order for this to happen, the frequency response of the speaker must be acoustically limited by the enclosure.

In a bandpass enclosure, the woofer resides between two separate chambers. Instead of playing directly into the listening area, the entire output of the speaker system is formed through a port(s). These ports act as an acoustic filter and limit the frequency response of the speaker to a specific bandwidth. Adjusting the size of the enclosure and/or the dimensions of the ports and the frequency response (bandwidth) can be greatly altered.

But why would anyone want to use a bandpass enclosure over a sealed or ported? Well, besides the natural filter acting as a crossover, a bandpass enclosure can deliver considerable performance benefits in terms of efficiency and low frequency extension that would likely not be possible in conventional designs of similar size. This of course is a tradeoff with regards to the parameters of the enclosure. When enclosure parameters are attuned for a narrower bandwidth, gains of up to 8-10 dB in efficiency are not uncommon within the bandwidth of the subwoofer system. Adjust the box parameters for wider bandwidths and low frequency extenion can be greatly improved, but at the expense of efficiency and good transient response. Using an intermediate bandwidth can create a compromise between these characteristics.

Bandpass enclosures come in two flavors: single and dual reflex. The more popular of these is the single reflex bandpass, otherwise referred to as a sealed rear chamber bandpass. In a single reflex bandpass, the rear of the speaker resides in a sealed chamber while the front fires into a chamber that is tuned by a port. This front chamber acts as a low-pass filter, which acoustically limits the high frequency response of the speaker. The roll off of this type of bandpass is typically 12dB per octave, much like that of the common sealed enclosure with better overall transient response.

Single Reflex Bandpass:
Good: can be very efficient within the bandwidth; controlled cone excursion at low frequencies; increased power handling within the band.
Bad: distortion hard to hear so it's very easy to damage woofers; relatively large enclosures; difficult to design and build; sensitive to design and construction errors; stressful on speaker joints and suspension.

Dual reflex enclosures are very similar in design to single reflex. The difference comes with the placement of port(s) in the rear chamber of the enclosure. This addition makes use of both the front and back wave of the speaker to improve efficiency over that of a single reflex. The additional port(s) also allows for extended low frequency response. In a dual reflex, the cone motion of the speaker is generally very well controlled within the bandwidth. But, as with everything there is a downside. This is apparent in the low frequency roll off that can be sharp, often in the range of 18-24dB per octave. This steep roll-off in the low frequency implies that a dual-reflex usually has to be larger in size to produce the same low-frequency extension as a single-reflex design. The low frequencies are a direct effect of the roll-off of the enclosure design; and as the enclosure is made larger to compensate, the transient response can degrade considerably.

Dual Reflex Bandpass
Good: can be even more efficient than a single reflex bandpass; excellent damping at resonance; broad bandwidth with extensions at low frequencies.
Bad: extremely difficult to design and construct; not very forgiving of construction errors; like a ported enclosure it loses woofer control below f3; steep low frequency roll-off (18-24 dB); very large enclosures; stressful on speaker joints and suspension.

In comparison to more conservative box designs, bandpass enclosures are can be very complex to design and construct. Their complexity leaves little or no room for error without suffering consequences. The slightest miscalculation in volume size or port length can create drastic changes in the response of the system. It is highly recommended that the design and construction of these boxes should be left to shops or people with extensive enclosure experience.

When it comes time to build an enclosure, it is important to keep in mind that there is no such thing as a "magic box." Every enclosure has its benefits that make it that better than the next design. No one box will yield the highest SPL, best transient response, smoothest frequency response, as well as power handling. So when it comes time to build the enclosure, be sure that you use the recommendations provided by the manufacturer to assure that the speaker performs the best that it possibly can. —Casey Thorson