Outstanding sound for commuters!

I've first heard the amazing Etymotic ER-4S canalphones at Headroom's World of Headphones tour. Never before had such high quality sound come from any pair of earphones that small! I was so impressed with their sound that I ordered a pair of them from Headroom.

When I received them a few days later, I proceeded to break-in the earphones. Then I tried putting them on, with the default supplied silicone rubber white tips. No problem. In fact, I was getting such a good seal with the white tips that the alternative foam tips (also supplied with the earphones) are rendered unneccesary. And with my ears building up earwax, I would have had to change the green filters (two of which had been pre-installed, with four spare ones supplied) more often had I used the foam tips rather than the white tips. The white tips themselves are quite comfortable for me to wear; I'm not complaining at all about ear pain unless I have them on for more than several hours at a time.

Trying the ER-4S's directly on my portable CD players (a now-broken Panasonic SL-CT470 and my current workhorse Sony D-EJ1000), the ER-4S's sounded okay, but a bit thin - and very revealing of the flaws of typical headphone jacks on portable CD players. While lesser-sounding headphones tend to mask the clipping distortion in the treble, the ER-4S's bring that distortion upfront (as I've now discovered from the previously-"distortion-free" Panasonic portable CD player). All that changed a week after I received the earphones with the arrival of a Headroom Total Airhead amplifier (which now uses three AAA batteries; the older version used two AA batteries).

Speaking of sound quality: Time and time again two words comes to mind whenever I listened to my ER-4S's. Accurate and detailed. You'll hear the bass, all the way to the lowest deep-bass notes - but you won't necessarily feel that bass. (I'd rather have audible bass than felt bass in a great-sounding pair of headphones, since felt bass often equates to overboosted and bloated bass in headphone listening.) The midrange is exquisitely detailed and neutral, as well: If a recording has crappy midrange to begin with, the middle tones from that recording will also sound crappy on the ER-4S's - but if the midrange on another recording is warm, the ER-4S's will retain that warmth. And the treble is well-extended and detailed, with a slight roll-off at the highest frequencies. This makes for non-fatiguing listening.

The ER-4S's provide the highest degree of isolation of ANY headphones (or earphones) that I've ever listened to. In fact, they block out so much external noises that they are useful on a noisy bus, train or airplane; you won't have to pump up the volume control as high as you would with other headphones in order to hear details in the headphone sound. But that isolation is like a double-edged sword: You must use considerable caution when you walk or jog outside with the ER-4S's on, and the microphonic cord noise will transmit through to your ears unless you can find some way of securing the cord to your clothing. And you can forget about riding a bike, skateboarding or rollerblading with the ER-4S's on; you must be able to hear external traffic sounds in such activities.

NOTE: In addition to the ER-4S, Etymotic Research also makes the ER-4P, which has a slightly boosted bass response, lower impedance and a higher sensitivity rating to make it more friendly for unamped portable use. And also available is the ER-4B, which has a flat diffuse-field treble response curve that makes it suitable for special "binaural" recordings - but that flat treble curve can actually make most commercial recordings sound a bit too bright.