What robert said makes sense and I'd like to second it. Only thing is, alot of people are going to want to use the 4S with small portable amps and whatnot and when you've got a jumbo plug plus and adaptor to change to a 1/8" you've just given yourself a big ol lever to unroot and destroy your output jack on your portable by prying it all to hell every time it's tampered with and bounces around in your pocket, etc. This is just what happens. So I mean come on guys. Really how much of a degradation in sound is it to use an adaptor for plugging them into big daddy? I really am ignorant on subject. I'm a total rookie, newbie, knows nothing snotnose, but don't they have goldplated, silver guts adaptors for that kind of thing that would keep everything shipshape?
As a matter of practicality, you know. If Don's listening, I'd like to see my idea come through, the straight plug short cord ER-4P (or the proposed 50 ohm ER-4X) for plugging into a remote would be sweet! But just being practical, I don't think that's something that Etymotics is going to consider. I'm putting all my enery into lobbying to get rid of the cord noise. PERIOD.
OH and of course. IDEALLY, modularly changing cables (duh) would just plain make EVERYTHING better. Wouldn't it? But Don has said that there are some serious problems doing that with trusting people to change their own cords, maintaining good connections, and with drivers casings becoming permanantly lodged inside peoples' ears if when they tug, the cord pops off (just kidding). But to work on that along with some ingeniously designed cord lenth/plug options plus NO microphonics would be an end all. (but a lot of work) It would be totally worth it to ety because no one would have ANY reason not to buy ER-4s other than money of course. And looking in from the outside..I'm no audiophile...That has never stopped any one of you!
edit: yeah and what BenG says is cool---a switch in the cord, but the the amount of extra work and stuff that goes into it, Ety would be better rewarded by working on modular cables (plus it'd allow for different lengths/plug options) because they'e get more out of it. If on the other hand everyone just had to go out and buy ONE set of headphones with the switch to change resistance and the option of changing to a 4B in the cord, then they'd either have to raise the price tremendously or none of that extra hard work and research and alteration in the manufacturing process would be rewarded. On the other hand I think the modular idea may be a little more rewarding for Ety and worth the effort.