Amazing sound isolation and fidelity

I purchased my ER4's last year more for use on aircraft or subways than specifically for their fidelity. They'd come highly recommended by a co-worker, and here I was definitely steered in the right direction.

Sound isolation with these is simply amazing. They are dramatically quieter than the ANC headphones I'd used previously (including the vaunted Bose QC2) without the ever present hiss associated with the noise cancellation.

Audio reproduction is impressive through the high and mid ranges, with only modest performance in the bass range. I've picked up details in some pieces with these phones that I'd never heard before. They're great for my usual music choices, but would probably deliver a bit too little bass for some pieces. Your mileage may vary.

The mixed blessing is the In-the-Ear design. They come with both flanged silicone and medium foam earpieces.

Down side is that getting the right fit can be a little tricky, and they can get uncomfortable over a long time wearing them. Ety has smaller and larger foam pieces available and you might get a better fit, depending on the shape of your ear canal.

Up side here is that the seal shuts out external noise (screaming child in the seat behind you drops out completely once the music comes on) and you can run your volume at incredibly low levels - I run at 1 or 2 on my Rio Karma, or at minimum volume if I plug into an airliner's audio system.

I got mine on-line for under $200 - much less than Ety's recommended $300+ price.