Performance

Judging the performance of an earphone processor and amp like the EAP03 is a challenging task in many ways. Because there is not a real competitor there is no benchmark for what is a good one. I have decided to test it against my main earphone amplifier which is a Ray Samuels Audio Tomahawk because they are both optimized for earphones. What you need to consider is the abundance of features that the EAP03 incorporates compared to a normal earphone amp. The earphones I used for testing are: Klipsch Image X10, Sleek-Audio SA6, LiveWires T1 Customs, Head-Direct RE2. They are all quite efficient with the RE2s being the hardest to power.

Strictly speaking, the EAP03 is not an all out portable amplifier it is not designed to drive demanding earphones with high impedance or a really low one for that matter. Its gain is adjustable much like a normal portable amp, but the circuitry behind is not designed to cope with high loads like a normal amp’s is. The EAP03 is designed to give you more options in terms of calibrating the sound to your liking. It has a complex cross feed system that can improve the imaging and a three band parametric equalizer. In some ways you can use the EAP03 to make up for the features you miss in your DAP or PMP. The hiss level of the Tension Labs processor and amp is low enough not to be noticed with normal earphones. You can barely hear it on low gain with a pair of LiveWires T1 Customs, but again its impedance is much lower and the efficiency is higher than what the EAP03 is designed for. In comparison to the RSA Tomahawk the EAP03 does not offer the same expansion of the sound stage even with the 3DX feature turned on. It is clear that in terms of sound quality some of the better portable amps will pull ahead of the EAP03, but they do of course lack a lot of the features that the EAP03 has.

I spent a long time playing with the parametric equalizer and it works really well. It does not degrade the sound quality noticeably in most cases. Although it is not as good as the equalizer in my Cowon players, it is certainly no slouch either. I tested the core performance of the amp by using it just like I would do with my normal amps and the sound quality was not as good as the Tomahawk. There were slight improvements, but nothing spectacular. The signal is pretty clean although not quite able to compete with the black background of my Tomahawk - it certainly comes close. What is great about the EAP03 is that the gain can be controlled in very small increments whereas on most amps you only get a choice of two to three different gain settings. The gain is however fixed after you dial it in on the EAP03 so there is no volume control on the unit which is a shame because you have to rely on the volume control in your DAP or PMP, and that means that you cannot use it with a true line-out.

The microphone system works quite good. The sound quality is alright and you can control the volume of it which is a definitive plus. It does a great job with mixing in the sounds from the world around you, but it is not quite omni directional so you mostly hear what is going on in front of you.

Durability

The durability of the Tension Labs EAP03 is far from as good as that of some of the better portable amps on the market today. But then again they do not offer all those advanced features that the Tension Labs device does. The EAP03 is made from plastic and the cabinet seems to be quite sturdy. The only things that are prone to breaking are the display and the scroll button on the side. If durability is a priority of yours you should probably look elsewhere.