mr56k, are you using ER-6, or ER-6i? You've said ER-6 a couple of times but ER-6i in the thread title and your sig, and the foamies you linked to were sized for ER-6i but not ER-6.
I'm just asking that for general purposes to set the record straight. It doesn't affect my answer to your question one way or the other.
If you like the Etymotic sound, then the next step up in my opinion is ER-4S plus an amp (a good amp, which I'll get to in a minute). Truly wonderful sound. Now, there are three pathways to ER4S-ness:
- ER-4P plus converter cable
- ER-4P plus Xin amp with internal converter
- an actual ER-4S
I started with a 4P, later bought a converter cable, later a Xin amp, and later had one of my 4Ps recabled as a 4S. Since buying the converter I have never again listened in 4P mode except for testing/comparison purposes; as I said above, it just sounds out of balance to me.
So if it were me buying at this point, I'd simply go for the 4S. But I think buying a 4P and a converter or a Xin amp is a perfectly good way to hedge your bets. However if you're willing to commit to a less efficient earphone, you can save a few bucks by starting out with the 4S. Since I always listen in 4S mode, for me the P->S converter is just one more thing to carry.
A couple more considerations in deciding between the 4P and 4S:
- the 4P ships with
new all-black cabling, while the 4S currently ships with the colored bits shown on
Ety's ER-4 page.
- from watching the for-sale forum, I get the feeling that a 4P is easier to resell than a 4S.
[episiarch pauses to put on his flame-retardant suit before continuing]
Now as for amps: now that I have the ER-6i, I have been forced to reconsider my amp collection. Some of my ER4-plus-amp combinations simply turned out - to my horror - not to sound as good to me as an unamped ER-6i. Your mileage may, of course, vary, but this is what I found, and it definitely was not in line with my agenda of feeling good about my portable amp purchases.
I mention this not to hijack this thread and turn it into an amp discussion, but because if you move up from ER-6i to an ER-4S plus an amp, you want to be sure you really are getting a sonic upgrade and to my ears, not all amps accomplish this.
From my collection, the amp+ER4 combinations that exceed the unamped ER-6i:
- Gilmore Lite. My reference sound. Incredible transparency.
- Corda HeadFive. Not as transparent and nuanced as the GLite, but very good.
- Pimeta with OPA627, running on either 24VDC Elpac or 18V from two batteries. Good.
Those that don't:
- RSA SR-71. It shocked me to find I liked an unamped ER-6i better than ER-4S plus SR-71, but I did. The SR-71 is a great little amp for most headphones, but paired with the highly resolving ER-4S, its treble rolloff becomes apparent and robs the Etys of some of the fidelity of which they're capable.
- Pimeta portable with 8620 and 9V. It's a little bright and unnatural with the Etys. I used to really like this combination for its great clarity, but now I just find it a little too tinkly sounding.
What about Xin amps? It is hard to say, because Xin changes them soooo fast. The one I own is a 2004 SuperDual, which was great for its size but a good notch or two below my 8620 Pimeta. The last one I heard was a SuperMacro of Spring 2005 vintage with OPA627 opamps which I thought was almost exactly on par with the 8620 Pimeta (yes, surprisingly). By now his amps have gone through additional generations which have presumably improved them. So they might very well be a good choice but I can't personally vouch for their being a sonic upgrade from the unamped ER-6i.