ety er4 questions: custom cables, custom earmolds

1. It really does it--I'm assuming that you are referring to the adapter cable (not the replacement cable, which also does it, but requires sending the phones to etymotic).

2. Send PM to fixup or visit his website (or search archives). There have been multiple discussions on reducing microphonics.

3. General consensus is that--if you get them made correctly--they are totally worth it. Try www.etymotic.com for a dealer who makes the molds.

4. The CHA47 sounds good with them. The Meta 42 also sounds very good with them (better actually), and better still is the Corda HA-1. Amp tastes are very variable, but these amps tend to come up again and again as the best with the etymotic (and I like all 3).

The adapter cable (http://www.headphone.com/layout.php?...tID=0050100000) is plugged in between the Ety's and the source. The replacement cable (http://www.fixup.net/tips/ety/ety.htm) replaces the physical cord, turns the 4P -> 4S, and reduces cord microphonics. The disadvantage (I've read) is that the replacement cable is not easily installed/changed. The adapter is easier if you want to change between 4S and 4P modes frequently.

The other thing you might think about, if you're considering getting a new amp, is that you can have the adapter built into an amp. This is probably what I'm going to do (I have 4Ps). The advantages of this are that a. there's no physical adaptor and b. they are automatically 4Ss whenever you use an amp, and 4Ps when you don't.

The cable should make the 4Ps the same as the 4Ss. I think that Etymotic claims better bass from the 4Ps because if the 4Ss are used without an amp, they may lack bass. In other words, without an amp the 4Ps will have fuller bass than the 4Ss. With an amp, obvoiusly, the 4Ss should sound better.

If you are very concerned about sound quality, you may want to check out this thread (http://www.head-fi.org/forums/showth...threadid=16970) that I started a while ago. In it, I asked about building the adaptor into a META42 amp. One member replied that this would actually improve sound quality versus having a seperate adaptor cord.

Please remember that I haven't ever used the adaptor cable, the replacement cable, or had the adaptor built in. What I'm presenting is just information that I have gathered from reading a lot of threads.

The fix-up gold-plug ER-4S replacement cable does better than the stock ER-4S cable in pure sound quality imo - the sound is 'faster, more revealing....', fix-up was right on the money in that description. (the fact the resistors are in the plug, as opposed to the mid-cable 'pod' of the stock cable, may largely contribute to the increase in sound quality - I don't know for sure) The cord is also less microphonic but NOT perfect in this regard, despite what the fix-up site may imply "....No more microphonic or wind noise. Period...."

The cord its self is less thick & therefore potentially less durable than the stiffer cord of the stock ER-4S cable. But the thinner cord does allow for easier cord movement. The cord its self is also shorter by 1ft 5in - not an issue for me but possibly a plus or minus for others. The plug (RS gold 1/8") is longer, easier to grip & potentially more durable than the stock plastic right-angle plug. You can also choose to have a 50ohm cable made, in addition to 20ohm or 100ohm.

I use a 50 ohm Fixup replacement cable. For me that's a good compromize in terms of balance, and it provides any possibility to increase the total impedance by use of further serial resistors. The Fixup replacement cable is not that hard to mount yourself, just note that the connection isn't designed to change cables constantly. The microphonics are substantially reduced in comparison to the stock cable, and I also think that the sound has improved with it, although it's hard to judge due to the slight over-all balance shift from the «S» to the «X».

Of course any serial resistor (increase) causes a loss of efficiency; so the «S» needs more power than the «P». But the impedance variation is indeed the only difference between «P» and «S» and the reason for the sonic differences. The larger serial resistors reduce the lower mids and the bass, without reducing extension, in favor of the upper frequency range, particularly the upper end.

I've done some mods with my ER-4. Instead of throwing a pair of used filters into the waste bin, I replaced the filter membrane by some foam and later by lambswool, and that really smoothed the highs in a convincing manner without losing details. And it gave me the possibility to fine-tune the frequency response. I definitely prefere it to the stock filters.

But the main sound difference is made by the foamies I use. They're actually pierced noise protection plugs. I put them over the transducer stem so that the filter tip is flush with the inner surface of the plug; the protruding flange prevents it from slipping completely into the foam, which tends to expand. I soon experienced that this way the filter soon gets clogged. So I put some nylon gauze over the stem before inserting it into the foam plug. That did help a lot – the nylon gauze is easily replaceable when it's dirty. To increase the low bass, I coated the whole foam plug with contact adhesive (probably rubber-based). Thus low frequency sound waves are trapped inside the ear canal and can't run through the air permeable foam anymore.

Anyway, it is to say that the stock silicon tips gave me a better isolation, but the sound is way better now. Especially the silicon tips virtually elongate the narrow canal inside the transducer stem. That's (obviously and logically) harmful to the sound, which naturally has the ear canal width at the disposal. And their slick surface causes much more reflective interaction inside the ear canal than the more absorbing foam. Thus with foam pads the sound is more accurate and «dry». But it's still shiny enough that way!

JaZZ