Summary

The Etymotic 4S is a fantastic bargain in an earphone - some say better than the Sennheiser 650. Certainly clearer sounding with better inner detail. Much of their appeal is that they fit into the ears and isolate you from ambient noise - reducing background noise by about 24 DB. Ancillary equipment is most important as always. I use a Lehmann Black Cube Linear headphone amp to use with my iRiver IMP 400 portable CD player and the Etymotic 4S earphones, in a car. I also use the Etymotic 4S earphones and Lehmann amp it with my home CD player (a Nad 240). This is a very good CD player - best for the money, though the newer 242 offers better capacitors with some slight sound improvement. With this combo of Etymotic/Lehmann/NAD I heard inner detail, lightening fast transients, clearness of tones, and a natural timbre that was magical on a well recorded CD. The Lehman is the best headphone amp for under $1000 and competes favorably with any headphone amp regardles of price. The car set up requires the use of an inverter that puts out 1 amp or more of 110 Voltage on a continuous basis - I paid $20 for mine. The Etymotic 4S earphones reduce ambient noise by about 24 DB and thus are perfect for cars. They are small and can't be readily seen from outside the car in case it is illegal to use them. Using earphones is no more danger relative to listening to a good car system turned up to a satisfying sound level - you drive by sight and not sound in either case. The car system is really great - the best sound possible in a car. The homw system is even better though the sound quality of the iRiver is not far behind that of the NAD. The Lehmann is the heart of the system and is a truly remarkable discrete zero global feedback Class A output amp that serves also as a single input pre-amp. You could use the sytem above without the Lehmann amp if you use the Etymotic 4P instead of 4S earphones, since the 4Ps are more efficient and the external amp is less necessary. The sound will be fine though not as good as with the Lehmann.

Strength

As described.

Weakness

None significant.