I'm surprised to see that the Q701s are an improvement to the K701s in EVERY way... even when a company tweaks the driver, there are always some small flaws that's brought in. A bit unrealistic if you ask me. I had the chance to audition the Q701s not too long ago, along with many other headphones. Here is my somewhat negative impression of the Q701s. However, I do acknowledge the possibility of having listened to a "bad" Q701 since the production of these headphones are apparently not consistent (like LCD-2). Nevertheless, I don't think the differences are to the point where one person will label the Q701 as good and another as bad.
First of all, there are a lot of people posting about the similarity between the Q701 and the HD-598. I can see the reasons behind the comparison (price, soundstage, bass neutral/lean) , but to me they are very different; the former sounds extremely unnatural while the latter is one of the most natural headphones I've heard.
The reason why I can't stand the Q701 is its soundstage. Funny because that's the characteristic that distinguishes it from all its other competitors. The soundstage is VERY wide, the widest I've heard. However,it has very little depth, and poorly pinpoints the location of every instrument. This isn't obvious for most pop music, but if you focus on certain types of music, the issue becomes obvious. Instrumental separation is - any many claims - good. But then again, I don't expect anything less from a $200+ headphone. The HD-598 by far has the superior soundstage. In fact, the best soundstage of any headphones I've tried (though I've yet to try the HD-800). It is not only wide and tall, but DEEP and is very realistic in its imaging. Vocals never sound distant due to its full and forwardish- midrange. I would actually take the Senn HD 6xx series - despite their far smaller soundstage - because it has more of a core to it, and therefore, engagement.
That brings up another point: timbre. Q701s have a somewhat plastic timbre to it. You get used to it after listening to it for long periods of time, but when compared side to side with other headphones, it becomes obvious that it's on the thin side. I found the Q701 to sound more clear than the HD598 but I think the difference in clarity was due to it sounding more thin. I found the 598 to sound more... "musical". Tonality wise, the 598 is FAR more balanced while the Q701s have more treble emphasis (which sort of takes away from the mids) and skewed towards upper mids (decent for female vocals).
The Q701s are a very attractive looking headphone, and is actually quite comfortable. The headbands do hurt but despite that, the clamping force is decent and I preferred it over, say, the HD-650. I did enjoy them for certain classical tracks; it was interesting to hear things from a different soundstage view. However, my concern for them is that they do not work for other genres as well. I felt that their biggest strength was their midrange and to some extent, their bass. I could barely hear the bass but the texture was decent for that level of quantity. But still, I expected more from an AKG flagship, and what people consider a "hi-fi" headphone. I'll take the "mid-fi" 598s over the Q701s anyday.
P.S. don't take my criticism too personally. If you enjoy the Q701s now, there is no reason to.
