Excerpt: I purchased a set of these for my home studio after using them in a variety of settings in the studio where I work. As others have mentioned, the bass response can be a bit deceiving. But I wouldn't recommend mixing with headphones alone anyhow. For composing/writing in the middle of the night or tracking live instruments, these headphones are perfect. (And much cheaper here, I might add).
Excerpt: Mine are still made in Austria, too bad the new ones are made in China. But nonetheless... These are excellent tracking headphones. Not very useful for casual listening, though they sound great, but not nearly as comfortable for any lengthy listening like an open back can would be.
Pros: Easy To Use, Excellent Sound, Low Distortion, Powerful
Excerpt: I use the K271 headphones for mixing my audio projects. The sound is great! They are pretty comfortable, though I have to take them off periodically to give my ears a break. Over long periods of time they start to be of slight discomfort, but that can be said about any headphones. The sound quality is great. The low end may be a little lean, as others have stated. But the response is pretty flat and the sound is awesome.
Pros: Clear Sound, Easy To Use, Lightweight, Versatile
Summary: Comfortable and accurate. I've tracked all day with these, and been the better off for it. I have yet to find anything I don't like about these headphones. My other pair of older K240M's seldom get used anymore, though due to the semi-open back of those, they are still more useful for general listening purposes. There's less sound leakage with these, and the build in switch that turns them off is very helpful.
Summary: When visiting recording studios in Europe or looking at the sales ranking of Germany's largest online store for musicians, the AKG 271 appears as the most popular studio headphone, well ahead of any competition. That isn't head-fi's major target group, but one should reconsider why and what for we use headphones. We want to listen to music in compromised environments, i.e.
Pros: neutral, comfortable, closed, cheaply replaceable cables and earpads