I did a review of these so here it is
The first thing I’ll talk about is amplification. Frankly, on a not so great amp, these sound awful. They’re thin, bright, shrill, sibilant and downright unnatural. Pair them with a good amp though, and the magic happens. As far as how to do that, a user has many options. For a solid state amp that gives some warmth and body to the K702 while maintaining its neutrality and cleanliness, the O2 or Matrix M-Stage are excellent options. The sound produced is extraordinarily exact – everything is tight and spaced perfectly without sounding overly clinical. Another option that a user has is adding tubes into the equation. Due to the 62 ohm output impedance, OTLs are somewhat difficult to use the K702 with (unless it’s something high end and powerful), however to add a tube flavour, a hybrid becomes a good option. To explain the difference in sound when paired with a Phillips 5814 tube on my Project Ember (reviews of the amp and tube can be found here
http://www.head-fi.org/t/675850/project-ember-review#post_9686059) , the sound on recordings becomes less clinical but not in a bad way. The sound becomes more relaxed and smooth with more body instead of an edge like a solid state amp. Imaging still stays spectacular, but loses a bit of the razor precision that the headphone has on a solid state in favor of a more musical, resolving presentation.
These headphones require a lot of burn in to sound their best. I think that a fair amount of the comments that call them thin and plastic sounding are due to the lack of burn in. I found them to be that way as well as a bit constrained sounding out of the box but with more hours on them the mids began to gain a thicker, more airy quality. The treble began to become a tad more tame, bass kick increased, and they became more open sounding as well. These are a headphone that I’d recommend letting play overnight for at least a couple of nights before listening to them if you’re like me and don’t want to wait until you log a bunch of hours listening for them to sound their best.
Now onto the review proper
First thing to talk about is comfort. I find the K702 to be extremely comfortable largely due to the fact that the headphones only clamp just enough to get a good seal and the pads are extremely large so they cover your ears easily. Some people find the headband which has bumps on it to be aggravating but I don’t find this to be a problem at all.
Next is soundstage. There isn’t much to say except that it’s extremely massive. Imagine there is a circle around your head and each sound occupies its own specific space and never once bleeds into the space of any other sound. Even in loud sections that present a wall of sound, the k702 manages to keep each individual guitar part separate. Instead of a presentation that presents a track as a whole, the K702 produces it as its individual parts played in different spaces. In certain parts of songs with sounds that come from seemingly nowhere such as Black Stacey by Saul Williams I have looked in the direction of the sound thinking that something was there and I’ve also thought that my speakers were on due to the illusion of space that the K702s provide. These headphones present as if you are about in the middle range of seats of a concert – still close enough to feel intimate, but not slammed against your ears like a Grado headphone would be.
Now onto detail retrieval. Every little thing is exaggerated in these headphones. That part in your favourite symphony when the person in seat 6B sneezes? You can hear it. The violinists bow bouncing when he plays your favourite violin concerto? You can hear that too. The little bit of vocal distortion that Adam Lazzara from Taking Back Sunday does on his vocals before he starts a phrase? You can hear that and it stands out in spectacular fashion. This is why it is extremely important to provide a sufficient amp and dac to these headphones. If you feed them garbage they will absolutely eat it alive. If you reward them with a good source and amp, it will pay dividends. These would be fantastic headphones to use as studio monitors because they are near neutral (other than a small treble peak) and it is very easy to zone in on individual parts due to the presentation.
As far as frequency response related things go
Treble: It’s a bit bright and can occasionally be fatiguing but that’s the beauty of these headphones. It’s insanely crisp and clear making cymbals sound wonderful and the upper registers of string instruments really pop. If you’re a classical fan, these are the headphones for you. If you find the treble bright, tubes are your best friend. I know some purists hate anything that distorts sound but as explained before, they provide some extra musicality and can really tame the treble to make it entirely non fatiguing and less bright if that’s what you’re after.
Mids: Some people will disagree with me, but natural is the first thing that comes to mind. As a violinist, these headphones produce the sound that is closest to what comes to my ears when playing of the headphones that I have. Vocals sounds amazing as well and have a wonderful slightly airy presentation that isn’t dark or bright. As far as what they sound like, they don’t sound like an actual voice but that isn’t the fault of the headphones — it’s that you can hear the production methods so well that it becomes apparent what methods were used to mic the recording and what work was (or wasn’t) done to clean them up. The detailed aspect of these headphones dominates how they sound at every stage.
Bass: This is where a lot of people complain about these headphones and I’m inclined to chalk it up to bad amping. From my Fiio E9 and Little Dot I+ when I owned them, bass was light and subpar. However on my O2 and Project Ember you can feel a solid kick from bass which makes these things perfectly fine to listen to rap and electronic with. In fact, I love them for those genres due to the fact that the soundstage and neutral presentation which is lacking on most headphones that are traditionally recommended for the genres provides a very different look at them. These extend very very low and instead of being bloated, the bass is extremely tight and snappy. As far as general speed goes, these are the fastest headphone that I own and it shows very strongly in the bass end of things.
As far as recommendations of what to listen to these with, anything goes. I find them to be an excellent choice for classical as that is where their detail shines most but don’t hesitate to turn to these for rock, rap and anything else.
If you're interested in reading more from me, I have a blog here
http://musicandlistening.wordpress.com/
and the WA22 in the background
when I can afford some LCD's again, I'll be keeping the K702's....
