Etymotic Research ER4SR Studio Reference Precision Matched In-Ear Earphones (Balanced Armature Drivers, Noise Isolating, High Fidelity, World Leader Response Accuracy)

I'm not really an audiophile, but I am professional video editor so I'm familiar with the requirements accuracy when I'm mixing audio for TV or other delivery systems. That being said, these are quite simply the most delicately accurate and enjoyable way to enjoy my favorite music that I've discovered yet in my 57 years on this planet. They isolate exterior noise so well, so that that you don't have to play them at full blast, and can enjoy the nuance and flavor of a recording as it was intended in the studio. To be honest that's enough for me. I play them out of an old fashioned iPod (The black one with the front dial), which is wonderful in itself, and then if I really want to bathe in luxury I'll add a good headphone amplifier, occasionally adding a little bass boost if I'm listening to music that seems to require it. But without the amp they are still wonderful. Buy them, you will not regret it you appreciate accuracy. If you need thumping bass added to your music like too much sugar, you're going to need a good amp or a different version of these. (I should add they take a little getting used to in the first week, as they go a long way into the ear canal, and you're unused to having anything in there.)

Very pleased with my purchase of the ER4SR.  The performance with my favorite music - classical, new age, jazz (no rock) has been excellent.  No complaints or disappointments. Really debated about getting the ER4XR v ER4SR.  Wish I could have listened to the ER4XR to make my choice.  Will never know the audio difference. No regrets but just wonder what heightened bass on ER4XR actually sounds like.