The splitter have the Etymotic logo on both sides. So I used a permanent marker and darkened one of the logos. So whenever I put these on, I orient the splitter and the wires and then I should have chosen the correct L R side.
If you like the ER4S then get the ER4SR. If you find the ER4S a little lacking in bass get the ER4XR. To me the difference between the XR and my old ER4S is about 3dB in Bass which not a lot but discernable. To me It does not affect other frequencies that much. Certainly not a bass heavy earphone and much better than the ER4PT. It is much better than EQing the ER4S which I do find masking some frequencies.
I had these ER4XR for about two weeks and I am really enjoying them a lot. I had the ER4S (PT with the 75ohms adapter) for many years and I found the bass a little lacking. So I always EQ'd a little to bring up the low end during low level listening. What they did to the ER4XR sound is perfect for me. It sound very close to the ER4S with that extra bass boost.
The cable is much better and less cumbersome. It is soft and you can wear it behind your ears. Still I had to...
One modification I made on these adapters. I drilled two holes on the PC board so that the cable comes out parallel to the drivers. This makes going around the ears much easier and flush. See pictures below
I made my own cable using 100ohms SMT 1% tolerance resistors. They are cheap enough so I ordered about 10 of them and measure the resistance to make sure they match. Here is my old post about how I did it. I really enjoy the cable: less clutter and I think sounds better than the stock cable because there is a wider channel separation.
Adding to the cable discussion. I made my cables just for comfort and elimination of microphonics. However I do notice that I get better channel separation and wider soundstage. It probably has to do with crosstalk difference between the two cables.
I can't say I understand it but I think it has to do with the signal from one side of the output amp bleeding into the other side's output amp path to ground through the ground wire. So in theory if we have separate...
You would have to put them in series on the signal side which is the thin post and the ground is the thicker post. Use 25 Ohms for a ER4PT sound or a 100 Ohms for the ER4S sound. The tip of the jack is the left channel, middle is the right channel and the outside is ground. Look at my post on http://www.head-fi.org/t/538615/if-you-still-love-etymotic-er4-this-is-the-thread-for-you/5610#post_11411686 about where I got the resistors and what cable I used. I really love...