It is possible to reduce the bass of the EP6s by a good bit if you enable Active Noise Cancellation, but there are also downsides to doing this. During the first week of writing this review, I felt the ANC mode hacked off a lot of the mid-range, leaving a thin tonal balance and fatiguing sound profile. However, as I spent more time with the EP6s, I found ANC does indeed improve overall tonal balance in some scenarios. The sound improvement of the ANC was experienced more often in BT mode rather than with a wired connection. The ANC also caused a shift in the spatial impression with more reverb during high frequencies, compared to the bass focused reverb with ANC off.
You will find that other EP6 reviewers believe ANC improves midrange clarity and response. I experienced this improvement at times, but it is far from always being true; as ANC impacts the sound profile from multiple avenues. Active Noise Cancellation (ANC) works by recording/monitoring the external noise in your environment using a microphone. Then the captured signal is inverted and fed back into the signal path, the result should be a cancellation of the external noises. The ANC on the EP6 requires you to be playing back something for it to function. I’m not sure exactly why, as many other ANC headphones don’t require music to work.
The quality of all ANC systems is highly time dependent, they must record, alter the recording and then insert it back into the signal, all very quickly. If the timing delay created by this chain is of any discernible amount, instead of canceling out external noise, you’ll just be inserting an additional source of noise into your signal! The ANC process usually adds in a slight delay in the sound when compared to the BT only mode, it’s most likely under 150mS. This delay is inherent to digital design, as each piece of logic hardware has an associated timing delay. If you focus on reverb and echo, you can hear the change in timing when switching between ANC and ANC off.
There are times where the ANC does in fact improve on the mid-range clarity of the EP6’s, but not always. Anything that is purely stereo tends to come out thin in the ANC mode for my ears. In contrast, most of the 5.1 content I tested seems to increase dynamic range in ANC mode. Speech playback quality in ANC depends on the scenario if the quality is better or worse with the ANC. The main thing is to remember the option is there, but it does cause a change in the sound-stage. Surprisingly, without ANC is usually the smaller of the two. This is due to the fact that a lower bass level can help create a better sense of openness (except in the worst case ANC usage scenarios), giving a lighter feel to the sound profile.
EP6’s ANC Delivery: 7/10
EP6’s ANC Quality of Sound: 8/10
Besides the issues in ANC mode with distortion and cutting the signal, the rest of the construction is adequately durable for $69.99 headphones. I believe it’s possible if the mics had been mounted or configured differently, the ANC mode wouldn’t cut the signal due to tapping. For anyone who intends to run or jog with these headphones on, this could be of real concern. I say this because the constant bumping from the up and down movements of your feet hitting the ground may cause the same thing to happen, repeatedly.
The overall design leaves us with at least one question, why are the volume controls in opposite positions from the standard locations? Battery performance appears to be near the stock rated 30 hrs, but this is highly dependent on your usage. The plastic finished used on the EP6 is prone to fingerprints as you can see in a few of the photos.