I have always enjoyed listening to music.  Even before my college days, when I spent four years as a radio DJ, I have enjoyed an infatuation with good music, particularly rhythmic and acoustic guitar.  I love slipping on my Ultimate Ears headphones and losing myself in the song.  Coupled with my Sandisk Sansa View, I am able to create an exceptional listening environment.  Perfect…or almost so.  The problem is, even this deluxe setting does not really allow me to fine tune my settings.  Well, now there is a solution for even the most discerning listener, the Tension Labs Earphone Audio Processor (EAP) 03.  Essentially, the EAP03 is an amplifier for your headphones, which will allow you to unleash the full audio potential of your high quality in-ear headphones.  To hear them tell it:

The EAP03 is the first portable digital earphone amplifier. Designed from the ground up to provide the power and customization needed to drive modern earphones. With a precision multi-band tone control and an audio expander function, the EAP03 is the only way to listen to your earphones. The EAP03 is fully compatible with all portable audio players and all in-ear earphones. Powered by a lithium-polymer battery and as small as a credit card, the EAP03 is as portable as your music.

The EAP03 uses the latest multi-channel audio processor with dual high-performance sigma-delta codecs to provide seamless control and customization for your audio. With audio level monitoring and a sound-level meter function, the EAP03 will allow you to actually know what your hearing.

So, let’s take a closer look at this EAP03.  Tension Labs advertises that it is about the size of a credit card.  And it is, though it is a bit thicker.  I would have called it about the size of the average portable media player.  Most of the controls are on the face. 

Here, you will find the monochromatic screen, which is used to display relevant information and menus.  Beneath that are two buttons.  The blue one controls the audio output, the red one controls the microphone.  Of course, the microphone is immediately beneath that button.  Finally, there is a small red LED light, which is the charging indicator.  If you plug in the device and that light turns on, then it is charging.

On the side of the device is a scroll wheel which can be used to navigate through the various options and menus.  Although I typically like scroll wheels, I found the operation of the wheel on the EAP03 to be counterintuitive.  Typically, with a scroll wheel, scrolling will take you to the next item on the menu, and pushing it in will select the current item.  With this one, pressing the scroll wheel will toggle you between the main screen and the menu.  Clicking the wheel up and down will take you through the menu items, however, to select an item, push the blue button on the face of the EAP03.  Pushing the blue button repeatedly will take you through the options of that particular menu item.  This really made very little sense to me.  These controls should all have been contained in the scroll wheel.

The bottom contains your connections.  Two 3.5 inch headphone jacks,and a mini USB port.

To connect the EAP03 to your portable media player, simply plug the included audio cable into the headphone jack on your media player.  Attach the other end to the EAP03′s Audio In port.  Then, plug your headphones into the earphone jack on the EAP03.  That is all there is to it.  Now, your music will be filtered through the EAP03 before reaching your ears. 

Also included in the box is a retractable mini USB cable which allows you to recharge the battery, and Velcro dots which will allow you to affix the EAP03 to your media player for easier transport. 

You are just about ready to use the EAP03 right out of the box.  All you have to do is charge the battery and set the sensitivity.  Different headphones will handle audio signals differently, and the sensitivity settings ensure that the EAP03 will be optimized for your specific headphones.  Settings for most popular headphones are included in the manual.  Others can be found at www.tensionlabs.com.  I am using the Ultimate Ears headphones which means they should be set at a sensitivity of 134. This is an extremely important step, because the wrong sensitivity level can cause significant damage to your hearing.

Your main interface with the EAP03 will be through the small monochromatic screen on the face of the device.  This is where all of your menus and options will be displayed. The main screen shows your battery level (it lasted about 8 hours in my testing) and the audio level.  When your music is playing, the audio level will be indicated by a number, as well as a dashed line on the bottom of the screen. 

To control your music, just tap the blue button to go into Audio Input mode. From here, you can:

• adjust the settings of the three-band parametric equalizer.  This is a fantastic setting for the true music enthusiast, which really represents a feature which is missing from many portable media players.  You can control the low frequency (bass), mid frequency, and high frequency (treble), as well as the low, mid, and high gain.
• change the earphone sensitivity
• activate 3DX Soundfield, which attempts to use your headphones to recreate the experience of listening to music on stereo speakers.
• change the amplifier voltage gain
• change the display setting can also serve as a hearing safety monitor by measuring how long you can safely use headphones at a particular level.  Setting this to time will cause the main screen to countdown the number of hours you can safely listen to music within a 24 hour period.

Pushing the red button on the face of the EAP03 will take you to Sound Level Meter Mode.  According to Tension Labs, this allows you to monitor the sound levels in your environment.  Which is a fancy way of saying that it will pick up environmental noises and transmit them to your headphones.  This allows you to listen to music and carry on a conversation without removing your headphones.  Of course, for most of us, headphones serve an important purpose of isolating us from our environment, so I rarely found a need to use this feature.

One frustration I did have with this device was the battery.  Because this device is so reliant upon an external media player, I would have expected it to be able to charge through the player.  This was not the case.  As such, if I had my media player plugged into the wall and hooked into the EAP03, the media player would be charging, but not the EAP03.  Instead, you must carry a separate cable and have two wall sockets available.  I found this to be extremely frustrating, as it meant that the EAP03′s battery was constantly running low.  At a minimum, Tension Labs should have included some type of splitter cable so that both devices could be plugged into the same outlet.

I used this device for a considerable period of time, and I found that when I used it, I could enjoy a cleaner, crisper sound from my media player.  In fact, if this cost $30, I would probably tell every man, woman, and child using in-ear headphones with their media players to run, not walk, to Tension Labs’ website and buy one of these today.  But therein lies the rub.  The EAP03 is going to set you back $180.  Ouch!!  This is as much, or more, than many media players.  So, after spending $150 or so on a media player, and then probably $200 on the type of higher end headphones this is really designed for, now you will be spending $180 on the EAP03.  While I felt that it did a great job of cleaning up my music; I simply do not think I could justify the casual listener spending that kind of money on a device like this.  However, if you are an audiophile like me.  If you have a preamp on your amp and can remember purchasing every piece of audio equipment in your home…well then, $180 probably seems like a small price to pay for this kind of sound quality and control from your portable media player. 

Vital Stats:

Name: Earphone Audio Processor (EAP) 03

Manufacturer: Tension Labs

Price: $179.95

Where to Buy: http://www.tensionlabs.com/index.htm