AKG K7XX

Honestly bass is bloated, mids are meh, treble is hard around 4khz. Just why? Soundstage is wide though and comfort is amazing! Now just the drivers! I am sad that they sound so bad. I wish they could just fix that and make the earpads just a little bit more comfortable they would be perfect

The AKG K7XX's are very popular in this community, and while I can see why, I'm personally not a fan. (Pls no haterinos, it's just a personal opinion)

Packaging: eh/10

Comfort: 9/10




Sound: 5/10
In my opinion, this is where the K7XXs really struggle, or at least differ from my own tastes. And no matter your taste in headphone sounds, these are definitely not "Reference Headphones" like they're marked. Apologies ahead of time for my lack of terminology.

Miscellaneous thoughts:

The 7xx is going to be one of my main stays that I keep around in case I need to adjust my ears back to a neutral sound, yes, kings of neutrality these phones hold nothing back about a recording, the detail retrieval is pretty stellar with good sourcing and amplification, slightly forward presentation but neutral and laid-back especially above the upper mids.
These don't have a lot of drawbacks aside from some crispness that can show itself on certain tracks but for the most part it is a phone that stays true to the source so it is recording dependent when that flaw can show itself.

Those that have blasted far off into summit fi land should come back and listen to some Yamaha HS80s or these AKG k712/7xx they seem to nail timbre and neutrality in such a way fancy colored gear cannot, sure you can listen how you like but listening to gear that helps clue you in to the studio mixing and where the rubber meets the road as far as music is made really helps you appreciate recording quality and musicianship. So no matter if you are new to audio or have an endgame setup, these phones are not hard to drive, they take to punchier amps better but are nice with sweet tubes, give them another listen. They are sweet little studio music machines.

Got this as a "replacement" for my K501s, has that same-ish AKG sound to it, comfortable all day listening headphones.
 
The earpads on these are superior to the old 501s, very big and comfortable.
 
Bass is a subdued, but its there in a very refined lowkey manner.
 
There is a big noticeable difference when this headphone is amped, a wonderful... addictive difference =)

 
Background
 
It’s safe to say that Massdrop has played a decent role in both introducing new products to the headphone community while highlighting others through their group-purchase system. The headphone I’m going to tackle today is their collaboration with Austrian manufacturer AKG, a Chinese-made version of their K702 65^th Anniversary Edition rebranded as the K7XX that retails for $199 on the site.
I had been interested in this headphone for some time now as praise has been showered on it for its price-to-performance ratio – with special consideration being given to its soundstage and imaging. I got my hands on one recently and this is what I found.
 

 
Specifications:
 
Configured by Massdrop
 
Manufactured by AKG
 
Open-back construction
 
Pre-selected dynamic transducers
 
Flat-wire voice coil
 
Varimotion two-layer diaphragm
 
Genuine leather headband
 
Memory foam earpads with velour covering
 
Individually tested and numbered
 
Detachable 9.8 ft (3 m) straight cable with 1/8 in (3.5 mm) jack
 
Frequency response: 10 to 39,800 Hz
 
Sensitivity: 105 dB/V
 
Maximum input power: 200 mW
 
Rated impedance: 62 Ohms
 
8.3 oz (235 g)
 

 
Build, Comfort & Features
 
 
I have not felt a full-sized headphone as effortless to wear as this since I sold my Beyerdynamic DT-990 600 Ohm. There is no incremental adjustment on the sides, much like the Meze 99 Classic, so you just pull it over your head and it stays in place. Comfort is supreme, absolutely supreme. The only issue I can imagine is during intense summer heat, which my locale actually had last week during a heatwave. Without air conditioning in such weather, the soft velour pads of the K7XX can get quite hot and bothersome.
 
The build itself can be described in a single word: plastic. That really is all there is to it. I was briefly fooled by one part and mentioned in my video review that it looked like a small piece of thin metal, but that is just brushed plastic too. While on one hand, this keeps the cost low and the weight light, these are not very durable and I’ve read of many accounts of creaking issues after some time of use.
The box really does not include much. Just the headphones, the cable and a small 1/8 to ¼ adapter. The cable is one of my favourite aspects of the K7XX as it is removable. I applaud such a quality showing up in a $199 pair of headphones just as much as I lament it not being included in $399, $449 and $499 pairs of headphones also being sold on Massdrop.
Sound
 
Before I even dissect the bass, mids and treble of the K7XX – I must address its most conspicuous feature. The soundstage is the widest I have heard yet on a pair of headphones, beating the previous champion of my list – the Beyerdynamic DT-990 600 ohm edition. The soundstage and imaging go hand-in-hand to create an out-of-head-space experience that truly lends credence to the term “surround sound.” A good test of such an attribute is a binaural recording, and this headphone was able to let me pinpoint a person’s almost inaudible movements while standing behind the binaural microphone setup. What really helps with the imaging is the speed of the headphones. They are in no way a planar magnetic level of speed, but they provide an excellent experience and fast transient response for $199. Panning audio in songs is effortless and not laid back at all.
 
I have read that the major change to the K702 65^th Anniversary Edition, and therefore the K7XX, from the original K702 was a three decibel increase in bass. How I wrap my mind around such a number is by imagining two bass ports on the ZMF Vibro Mk. I that I used to have, each one controlling one-and-a-half decibels of bass. With that knowledge, it is a substantial increase and by no means a basshead-pleasing one – but one to round off the low end and add body to the music played. Due to this, I would not characterize the K7XX as being a bright headphone but rather a warm one. The bass is fast but, obviously, not planar magnetic levels of fast but it is very smooth. There is definite roll-off so some genres of music would not be suitable for use – such as really bass-dependent EDM and hip hop tracks.
 
The midrange gives a clean feeling to it. It is not recessed, stark nor syrupy sweet – like the Hifiman HE-500. It’s just there, and vocals and instruments utilizing it will be heard as such. It just exists, if that makes sense. If the K7XX was a sports team, the midrange would be a role-player and not the star of the show – which the soundstage is. By all means, do not take my words as negative in this matter because music does sound quite full bodied in the midrange for most genres. It’s just those certain times where you feel like vocals and instruments sound a little thinner than they should. This could probably be changed with the right amp setup, for I do hear a slight improvement using my Cavalli Audio Liquid Carbon in this regard.
 
The treble takes my old term of “comfortably extended” and raises it just a slight amount more. Suddenly, there is more sparkle to music and the “air” around instruments is more distinguishable. Sibilance is only reached rarely in music that was not mixed/mastered properly. One can be grateful for the treble extension and detail because of how drum cymbals are so easily elevated from the rest of the instruments, and then be grateful for the immense soundstage because where they can rest in the mix accurately.
 
Is it a performer? Absolutely. Will it take down the more expensive and heavier hitters in the audio world? Not really. While the sound itself has been a welcome surprise for the price range, the actual selling point of these headphones is definitely just mid-fi all-round usage and immense soundstage. This actually influenced me to come up with a new sub-section for this review.
 
Gaming
 
Yes gentlemen and gentler men, the K7XX is by far the absolute best gaming headphones I have ever heard. If you have the budget, and it is indeed a budget you will require for reasons that will follow below, then do away with your Razer, Steelseries, Kingston and other gaming headsets and buy these instead. I have not had a comparable experience with audio clarity when it comes to gaming from anything I have owned before. I play Overwatch these days and every footstep and ability trigger/voiceover rang out incredibly in the overall game sound design thanks to how well the K7XX was keeping up.
 
All those aspects that gaming companies’ marketing divisions like to yell about is indeed present in the K7XX, to a realistic level. You can actually make out where an enemy is by the sound of their footsteps growing louder or softer in a direction. Will it give you that L337 gaming edge you’ve been looking for since you first jumped into Call of Duty: Modern Warfare’s online-mode? I can’t say, only you can, champ.
 
Amping
 
This is where it gets a bit tricky. You might be fooled by the 62 ohms impedance of the K7XX, but these are not very easy headphones to drive. They are nowhere near Hifiman HE-6 levels of difficult, but they do need proper amping if you want to enjoy all aspects of its sound. I have three amps in my possession and let’s see how they compare:
 
Cavalli Audio Liquid Carbon
 
While this amp adds a little body to the midrange due to its warm characteristic, my specific model is not one I would pair with the likes of the K7XX because it does fall into the “low impedance” realm that is problematic with some first run Liquid Carbons such as mine. There is a humming issue, greatly exacerbated if on high gain (which I don’t recommend with these headphones in general).
 
Venture Electronics RunAbout Plus
 
This portable-sized amplifier actually packs a good punch to it and a sound signature that isn’t quite warm but isn’t quite neutral. It even drives my ZMF Omni, a planar magnetic Fostex T50RP mod, somewhat decently. However, the K7XX loses a fair amount of its bass response and tightness when paired with it. It’s the same problem I notice if you try to run the headphones through the likes of a smartphone, the bass becomes quieter and a tad distorted.
 
Schiit Magni 2
 
I keep calling this “probably the only amp you’ll ever need” and I keep being proven right. The clean power that it provides synergizes very well with the K7XX. I keep it on low gain and it is more than enough to control the bass and have the sound blazing on all cylinders – just don’t expect an especially melodious or magical pairing. It is just adding volume and power, nothing more.
 
Conclusion
 
I am satisfied with the K7XX. That is the best way I can put it. I didn’t expect magic but I did receive some in a small way, the soundstage and imaging is a great selling point as it its allrounder functionality. In terms of build, mine don’t creak so much and I bought them used so your mileage may indeed vary if a new pair starts to do so after a few weeks.
 
Ultimately, I see the K7XX as a very capitalist pair of headphones. This took an item that was limited edition and priced over $400 and brought it down to $199 simply by switching some build materials and moving production to China. However, unlike Walmart, you can’t really hate on Massdrop and AKG for the birth of the K7XX because it is indeed bringing a quality headphone within the reach of those who are starting out in the audio game or those who want something relatively inexpensive but different to complement their main set of cans. If you can amp it, go for it I say. I’ll be using these for gaming and movies for sure.
 

 
 
 
Comparisons
 
Bass Quantity: TH-X00 > Classic 99 > ZMF Omni > ZMF Vibro Mk. I > HE400i > DT990 > K7XX > HE-500 > HD600
 
Mids: HE-500 > HD600 > ZMF Omni > Classic 99 > HE400i > ZMF Vibro Mk. I > K7XX > TH-X00 > DT990
 
Treble Quantity: DT990 > HE400i > TH-X00 > K7XX > Classic 99 > HE-500 > HD600 > ZMF Omni > ZMF Vibro Mk. I
 
Soundstage: K7XX > DT990 > HE-500 > ZMF Omni > HD600 > HE400i > ZMF Vibro Mk. I > Classic 99 > TH-X00
 
Comfort: DT990 > K7XX > TH-X00 > HE400i > HD600 > ZMF Omni > Classic 99 > ZMF Vibro Mk. I > HE-500
 
Aesthetics: Classic 99 > TH-X00 > ZMF Omni > ZMF Vibro Mk. I > HE400i > DT990 > K7XX > HE-500 > HD600
 
Lightness: Classic 99 > K7XX > DT990 > TH-X00 > HD600 > HE400i > ZMF Vibro Mk. I > ZMF Omni > HE-500
 
Song Impressions
 
Equipment used: Foobar200 WASAPI Event > Schiit Wyrd > Schiit Gungnir USB Ver. 2 > Venture Schiit Magni 2.
All tracks in lossless FLAC in at least 16/44.1
 
Aerosmith – Dream On (2012 Remaster)
 
A headphone’s soundstage always makes or breaks this song in my opinion. With the ability to space out and separate the instrumental, the K7XX does this song justice in a manner that is out of reach of headphones like the TH-X00. The low end is not overly bassy, but well-rounded so that the bass guitar finds itself comfortably in the mix. Nothing is drowned out either in the instrumental.
 
a-ha – Take On Me
 
While missing the incredibly low reach of the TH-X00’s sub-bass, the K7XX does an admirable job of opening up the song’s instrumental and vocal layering so that the 80s synthesizers have more of a sparkle to them – so far removed they are from the low end. The superior imaging of the K7XX really plays well into the panning synthesizer runs in the bridge section.
 
Alan Parson’s Project – Sirius
 
This track synergizes very well with the K7XX, which delivers warmth and body to the low end while maintaining a treble extension that allows the shimmering string section and synths to stand out in the mix rather effortlessly. The song is a builder, and every instrument is represented well as the layers stack.
 
Black Sabbath – Planet Caravan
 
While the soundstage is undoubtedly incredible, there is a certain artificial nature to Ozzy’s voice in this song compared to the likes of the HE-500. I chalk this up to the superior mids of the Hifiman headphone. The piano on the left channel at the end does not sound as natural either. Not by any means a poor listen however – owing to the really good allrounder status that the K7XX has.
 
Prince – Controversy
 
While not oozing effort in the midrange, the K7XX does quite a good job at holding the song’s driving nature at the seams. The presentation is disciplined, but the sub-bass of other headphones in my possession is missed for that oomph sound in the beat.
 
Billy Joel – We Didn’t Start the Fire
 
One of my favourite listens with the K7XX. The production gels with the strengths of the headphones to provide a complete and fun listening experience. The overdubs ring out clearly due to the large soundstage with the bass-boosted nature of the headphones providing a good sense of fast pacing with the kick drum.
 
Blink-182 – I Miss You
 
The two acoustic guitar tracks ring out incredibly on the two channels. Not quite a punk rock song by a pop-punk band, the mature melody and instrumentation is really well served by the K7XX on all fronts.
 
Chris Isaak – Wicked Game
 
I return to this song with every song impression and with good reason as it is very good at highlighting the strengths of various headphones. In this case, as aforementioned, the incredible soundstage benefits the song in a large manner. The warmth also makes the acoustic guitars sound rich and lifelike. However, the vocal is not as pleasing as it would have been on the HE-500 or ZMF Omni, but one must consider the incredible price differences in making that comparison. As also mentioned before, it is still a great listen on its own and quite excellent for $199.
 
Clint Mansell – Lux Aeterna
 
As the string sections creep up on the listener, the fast nature of the K7XX comes into play as the whole presentation is very controlled and effortless. The different sections are spaced out well. The higher pitched main melody, played on a violin, maintains a decent amount of air around it but not an incredible amount due to the extension of the treble being as a “comfortable” level. What is most impressive is that I can name a number/degree from 0 to 180 for exactly where each string section is in the mix.
 
Coldplay – Clocks
 
The K7XX separates the tracks incredibly in this densely layered track, giving the backing ethereal synth-pad a lot of body. The piano rests in the right channel, far from the guitar work on the left – all while Chris Martin’s vocal rings out above it all.
 
Eminem – Without Me
 
I was taken by surprise here, the 3 dB of bass bump that is present on the K7XX compared to the K702 really shows on tracks like this. While the bass is not the centre of attention like it is on the TH-X00, it isn’t entirely lacking either. If anything, the whole song sounds “clean.” The extended treble makes the snare and hihat bite through the mix however, something to consider if you are treble sensitive.
 
Fleetwood Mac – Dreams
 
The cymbal on the right side is further to the right than with any other piece of audio gear I own currently, another fact attesting the vast soundstage. The bass guitar work does not feel as tight however. The vocal layering in the chorus is not as rich as the HE-500 either. What is done the best is the sense of space and the treble lending a decent amount of air to the production.
 
Metallica – The Unforgiven
 
The Black Album probably has the best production on a Metallica record to date, but it can feel a bit hollow on some headphones due to how much it relies on low end and midrange body. So what I hear is a lot of sparkle in the cymbals and crashes but not so much weight behind the guitar section except with the acoustic guitars kick in in the intro and chorus. The guitar solo however sounds pretty good, with its overdubs adding to its presence. However it is only a small section of the song.
 
Thanks for reading my review. If you enjoyed this, please check out my new website where I put all of my work in both written and video form. www.aornic.com
 
You can also follow me at:
 
Facebook: https://www.facebook.com/aornicreviews
 
Instagram: https://www.instagram.com/aornic
 
Twitter: https://twitter.com/aornic1024
 
Soundcloud: https://soundcloud.com/jesuschristonxtc
 
YouTube: https://www.youtube.com/aornic

AKG K7XX
As should be obvious, I’m not a professional reviewer. Heck, I’m not even a frequent reviewer. But every now and then, I do get a desire to throw my $.02 in an interesting headphone or other piece of equipment. In this case it is the AKG K7XX, straight from Massdrop.

One of the things that keeps me in this hobby, is I just love headphones. I am always seduced by the magic that emits from the transducer. I am also entranced at the thought of the miniature room sitting on top of, or near, my ears. Every experience is different and every headphone seems to carve out its own particular niche.

These headphones have garnered enough attention that I couldn’t resist the most recent drop. I’ve read glowing reviews, with one member who I really respect, referring to them as giant killers. Really? For $199? I just had to try them, especially since for the past 4 years I’ve mostly been listening to planars from Hifiman and Mr. Speakers.

Before you read on, I will state right out the gate that rarely have I heard a headphone that I disliked so intensely from the first few minutes I wore them. In fact, my initial review was written with a one star in mind. That’s just how much I do not like what they do, although I can certainly understand why some people think this is one of the greatest bargains in headphones today. But at this moment, I have to be “that” guy who really dislikes something that’s almost universally loved. Let me explain…

BASS
A lot of people believe the bass is one of the most important aspects of a headphone. I totally agree with this, but for me it’s a matter of quality and not quantity. I have to admit; the 3 dB bump that AKG claims is compelling. It is there, and it’s rather tastefully done. But unlike other commentators on these headphones, I find that it does come at the expense of macro and micro detail.

And this is the thing that really bugs me about these headphones. A slight bass boost is always a nice thing, except when it interferes with the overall presentation. Especially when it comes to percussion. There’s something about the bass on these headphones that “veils” the kick drum on a lot of the material I love to listen to. These headphones just don’t have the visceral impact I value so much in a speaker or set of headphones. Now, Grado’s are not known for their bass, but the presentation of the bass guitar or a kick drum on my Grado SR-225i’s (with tape modification) is very distinct and clear. But the K7XX’s just don’t present those instruments as clearly and distinctly as I want.

MIDRANGE
I have very little to complain about regarding midrange overall. But that pesky bass boost gives a bit of chestiness, for lack of a better word, for vocals – especially male. Even female vocals are affected somewhat, though not nearly as much. It’s as far from “natural” as I have heard in the past couple of years.

However, the presentation of electric guitar, keyboards, and even stringed instruments is pretty good. In fact, they’re a bit above average. What is most impressive is the lack of distortion. Once material gets dense and complicated though, the mids tend to lack clarity and definition.

Going back to drums and percussion, they have very little impact. I don’t get the sense of “smack” when the stick hits the drum. For most people this might not be a big deal, but for this guy, it’s maddening not to hear that or sense that. For dynamic headphones, these just don’t seem very dynamic to me.

TREBLE
For the most part, this is their strongest presentation in the audible range. Virtually no sibilance that I could detect, regardless of material. Really good detail retrieval in the upper range as well. Most importantly, these are extremely non-fatiguing headphones. Their treble presentation makes them very easy to listen to, for extended periods of time. If you love how they sound overall, this is awesome.

IMAGE/SOUNDSTAGE/DEPTH
Okay, here’s the part where I expect a number of people to totally dismiss this review and move on to something else. By far, the strongest aspect of these headphones is their soundstage. It is wide, and under the right circumstances, they are impressive. My problem with it is it seems unnaturally so. Yes, this is because I listen to a lot of Grado and other headphones that have a more limited soundstage.

But it’s also because the depth of the soundstage is very, very shallow to me. It’s wide, and I can hear where that is fun. But it’s at the expense of imaging. By that I mean vocals seem out of proportion and larger to me than I usually experience with my other headphones. This is where I have a problem with their imaging in my head. Which reminds me, these headphones are more “inside my head” than any other set of headphones that I own. I experience no illusion that anything is in front of me. It’s all right between my ears, which when I wear them, is about 10 feet wide.

ON THE OTHER HAND
By now, it is probably clear that the AKG-K7XX headphones are far from my favorite headphones. In fact, up to this point, they are by far my least favorite that I have heard to date. I posted some impressions on the K7XX thread, and got a few suggestions for trying them under different circumstances. But it didn’t matter what the source was, didn’t matter what the amplifier was, and it didn’t matter what I was listening to. I just don’t like these headphones.

Then, I decided to watch some older episodes of “The Walking Dead”. My girlfriend is not fond of the show, so I watch it pretty much alone. Which means, I use headphones- usually the Alpha Primes from Mr. Speakers. But this time, I decided to give these a chance through my receiver, a rather average Marantz SR-7008, not a receiver generally regarded as a great headphone amp.
It was like a revelation. Almost every single objection I had up to this point regarding these headphones disappeared, and I enjoyed television on headphones like I have rarely done before. The soundstage was wonderful and everything is perfectly placed, from the birds in the background, to the zombies eating flesh in the middle. They came across is dynamic, impactful, fun, and a much better headphone for this purpose. I thought for sure I would keep them…


IN THE END
To sum it up, I was initially quite disappointed in these headphones. Music just came across as flat. Even the wide soundstage seemed to lack depth or excitement. I couldn’t enjoy any music on them at all, no matter what source or amp I used. I wrote in another tread that I can see why people love these so much: I just don’t hear it.
However, when I used them for movies/TV, the whole thing flipped for me. I’m glad I kept trying with these, because I would have missed out on an experience that I found enjoyable and in many ways, practical.
Overall, I have to rate these as a marginal “3”. They are worth the money if one favors their signature, have no apparent quality issues, and fit a very specific want of mine. But not a need. Gamers, video enthusiasts, and soundstage fans might indeed find these to be the deal of the decade. For me, they’re just a set of headphones that do one thing that I value very well. The rest- they’re okay.

TEST TRACKS
Cowboy Junkies- Crescent Moon, Mining for Gold, Misguided Angel
King Crimson- Indiscipline, Asbury Park (live)
Black Sabbath- Into the Void
Taylor Swift- Red
Lo Pan- El Dorado
Porcupine Tree- Arriving Somewhere, Trains, Anesthetize

TELEVISION SHOWS
The Walking Dead: Season 6, episodes 1 through 6
Vinyl: Season 1, Episodes 1 through 3

ASSOCIATED EQUIPMENT
Shiit Modi and Magni
Benchmark DAC-1
Cavalli Liquid Carbon
Burson Soloist
iPhone 6S
ipad Air 2
Oppo BDP-103
Sonos Connect

The K7XX is a set of cans that has earned some extremely high praise since its burst onto the audiophile scene roughly a year ago through group buy vendor Massdrop. Some of which is deserved, some... not so much. The headphones are essentially a rebranding of the extremely popular K702, with a slightly enhanced bass response to appeal to the beginner audiophile (people like myself).
 
The built quality of the K7XX is adequate, its construction mainly consists of plastic, with a genuine leather headband which is adjustable via elastic tethers. Personally I'm not a fan of the elastic as all elastics that I've encountered, especially ones that are constantly stressed when in use, tend to wear down fairly quickly. The general build quality is not quite up to par with direct competitors like the DT880, with its metal adjustment arms and foam/leather headbands. That being said, I've had these for a year now with very common use and the plastic and elastic has shown no sign of degradation. In fact, while almost the entire construction is plastic, they honestly don't feel like they're going to fall apart any time soon.
 
The comfort that comes from the attractive design and enormous ear cups is second to none. If you're the type of person that is easily distracted by contact with the drivers or ear pads of your headphones, you'll have no problems at all with these guys. Speaking of which, the memory foam ear pads that AKG have chosen to use is delightful. Personally, I would've preferred a soft plushy foam, such as that used in mid-to-high-end Beyers, but these do very well in their own respect.
 
What really matters is: how do they sound? Well, if you're on the market for an almost-neutral set of headphones, but don't want to lose too much of that bass you've grown to love, look no further than the K7XX. Now, keep in mind, these are definitely not a bass-lover's headphones. If your music collection consists of a lot of EDM, rock, or other bass-heavy genres, you may want to look elsewhere. Personally, I listen to mostly rock and psychedelia and have these on rotation with Beyerdynamic DT990s, and I vastly prefer the listening experience obtained with the latter. This is just my personal taste and I still have great respect for the analytical signature of the AKGs.

I got these from the forum. They are First edition.
 
Looks: The look is slick. Big earcups, all black, clean look. (though not important, who wants headphones to be ugly?)
 
Build: I very much like the overall build.
The earpads are pretty good. The material is not uber cushy, but has a memory effect to it. No complaints, and quite nice.
The cable is not braided  , but is removable, and still miles better than the HD558 spaghetti cable. Mini XLR connector is somewhat proprietary, but i actually love the connector style.
The headband is real leather, but I think it will take some time to soften up. I found it annoying.
The overhead bands are cheap, but they work fine. Not really a negative.
Thankfully AKG decided to go with a large earcup. This is a huge thumbs up!
 
Comfort:
The first thing i noticed when I put these on is how much the headband dug into my head. This is annoying, but you can rotate the headband slightly, which mostly solved this problem, yet not entirely.
Next, the Earcups are plenty large in height, and width for the majority of ears. My ears are close to pushing the limit on height. My ears stick out a bit, and thus touch the inside of the earcup quite a bit. It is padded though, making it good enough, but a bummer for how much I love these. 
 
The pad dimensions are:
Inner Width: 70mm 
Inner Height: 70mm
Inner Depth: 20mm
 
Because they are so large and round, the depth seems a tad lower to me.
The clamp is enough that they do not slide off. As someone who had high sensitivity to clamp pressure, These are not a problem at all. Not perfect, but not bad at all. The K7XX are more comfortable than not. I have yet to find anything up to my very high standard of comfort yet.
 
Sound: Yes. Just Yes.
I waited to write this review until i had received all the headphones I recently purchased to arrive. This includes the Pioneer SE-A1000, HD558, SHP9500, Fidelio x2, and the AKG k7xx.
 
I will put these in order of cleanliness.
1. SHP9500
2. K7XX
3. SE-A1000
4. HD558
5. Fidelio X2
 
The thing to note here is that cleanliness is not all there is to sound. I get the most resolve out of the SHP9500, but that does not mean they have the best overall sound quality.
 
This is very important in this case because I think the AKG K7XX has better overall sound quality than the SHP9500. The SHP9500 does give a tiny bit more clarity, but the amount is not very much, and sometimes would say it's a tie, or a small victory for the K7XX. The place where the K7XX beats the SHP9500 is in the low end. There is more bass, more attack, and just more complete sound. The K7XX has the edge that the SHP9500 lacks. The K7XX is more full, and still keeps all the clarity. The only reason I put the SHP9500 ahead on the list is the lesser bass allows the other ranges to be  clearer. The SHP9500 is also quite grainy compared to the K7XX, which is far smoother. The K7XX is the superior Headphone.
 
The sound of the K7XX is pushing toward the analytical side of the equation, but had enough warmth to keep them from sounding sterile. They fall into the Jack of all Trades category for me. They are never the absolute best at any one thing, but are collectively the best headphones I have had yet. If I had to sell all but one pair of open headphones, based on sound I would keep the K7XX. They are not super dry, but keep the clarity, and neutrality. 
 
On a side note, I can hear a treble spike (maybe 7KHz?) I have cringed a little at times from this, but not really much of a problem.
 
Compared to the Fidelio X2, These have way better treble and upper mids. The bass on the X2 crush most other open back headphones, but I do not miss them so much withe K7XX. There is enough bass that they are not anemic, and I can feel it sometimes. While the X2 lie to you in an exciting way, the K7XX tell the truth in a not-super-boring way. My neighbor across the hall seems to find the K7XX boring. He much prefers the sound of the Pioneer SE-A1000, but was not a fan of the X2, saying they had too much bass.
 
Personally, I freaking love how these sound. Nothing sounds bad on them. The X2 left me without good enough vocal, the SHP9500 left me wanting bass, the K7XX sit somewhere between the two, and Fill the gap in a wonderful way. They are not exciting, but I do not find them too boring either.
 
 Recommended song:
Crystal - Fox Stevenson
 
In essence: These sound fantastic. I recommend these to all the people who just want a single pair of headphones that do everything well.
I think most people will find these very comfortable.
 
EDIT: Those of you who have asked me about an upgrade from the HD558, the AKG K7XX will not likely disappoint!
Also, I now have the HD700, and I like them more.

I have been an Audio Technica guy for the last 20 years or so.  I have the AD700, A700, AD900X, M50, ANC27 plus the Sony 7506's.  I was looking to try an AKG and had been trying for a while to win a set of Q701 Quincy Jones Signatures on Ebay when I saw a post on Slickdeals about the AKG K7XX (First Edition) for $200 on an unknown site to me called Massdrop.  After reading the discussion about them claiming K702 Anniversary sound with improved bass I went for it (serial # 2255) and they are now my go-to phones.
 
Sound:  These are silky smooth and clean but still can be very dynamic and fast when they need to be.  While all of my other headphones have their pluses and minuses these can match up to the strengths of each of them nicely. The bass is very close to the level of the closed back M50 but cleaner.  Drum solos sound more real than I have ever heard them, tight and clean and you can easily tell differences between each drum.  The members here said that the K7XX would need and amp so I bought the Fiio E12 to use with it and it definitely helps give the K7XX a stronger dynamic presence.
 
The sound-stage is second only to my AD700's (the purple pasta strainers) but the base is magnitudes better.  I am not a bass-head so the K7XX has more than enough low end to satisfy me.  As I am writing this paragraph I am listening to Freebird and the bass is nice and tight, better than open backs usually are.  The mids are also better and more open than anything I have heard,  Female vocals have always sounded great on my favorite open backed AD900X's but the K7XX is still better and the highs blend in nicely without any listening fatigue.
 
While I think the K7XX is fairly neutral they are not flat or boring.  The 7506's don't have the presence these do and just seem limited and sound small after listening to the K7XX.  The sound-stage is large and makes you feel that the music is all around you rather than coming from headphones.  These are large phones and don't have a problem filling the whole room (between your ears) with sound.  Now I mostly pull out the K7XX by default instead of picking a set of phones for what I want to listen to.  Since everything I have played on them sounds as good or better than anything else I have heard they are the one headphone I can't be without.
 
Comfort:  These one of the most comfortable headphones I have ever used. Made from lightweight plastic (8.3 oz.) and with the over-sized memory foam velour ear pads I wear them 4-5 hours some nights and never have had to removed them.  There is hardly any clamping pressure, they use a form of self adjusting band on the top that adjusts elastic bands on each side to the right height.  The larger Audio Technica models have a self adjusting wing like mechanism that is also works very well and that I really like but the K7XX seems to move around less.  The headband doesn't have any padding and my only concern is that it feels a little slippery.  If the headband had a little more grip I think that it would be the perfect system for a comfortable but still secure fit.
 
Value:  Well I am a guy that stays around the $150 to $250 area.  I find that that gives me the best sound for my money. The AKG K7XX is heads better than anything in it's price range.  It might only be due to the Massdrop group buying club that I got these for $200 but that is what they sold for so I am basing my rating on the price.  I think that I have the best headphone that can possibly be bought for this price and will probably have to move up to the $500+ range on my next pair to feel that I got a worthwhile improvement.  I would like to try a planar magnetic next, maybe the OPPO PM-3 or Hifiman 400i but for open backed dynamics I can't imagine anything under $500-$800 being better than these.
 
Conclusion:  This is my first review and I know that it is incomplete and amateurish in depth and format but there is nothing not to love about the AKG K7XX.  I didn't post any new photos as the ones that others have posted are much clearer than anything that I could have done.  I didn't know that ear-pads could be so soft and comfortable.  That a headphone as large as this could be so light.  That you can get this good a bass from a open back design with this large of a sound-stage. Or that one headphone could replace several that I had been using with different music genres.  If you don't have a pair of AKG headphones then I think you will be very surprised at what you can get for $200.

First off, this is my first real pair of "audiophile" headphones. After about of year of research I came upon massdrop and these beauties, all black, Austrian design, and legacy of great open backs to back it up, for only 200$! I can very much get behind this. Although I was disappointed to hear that it was being produced in china instead of glorious Austria, the pros to this over the k712 and the k702 seemed pretty great. The new headband, the slightly altered drivers, etc. It all seemed like a great deal, so I went with it, and boy oh boy was it the right choice. These cans are amazing. First off is the comfort. It uses the elastics attached to the headband to make it seem weightless on your head, that coupled with the memory foam velour ear pads make these incredibly comfortable. Alright onto the sound!
 
Serj tankian "fish don't scream"
This song is kind of my standard for bass because its very well recorded and starts out with a bass intro, the bass sounded clear and loud but not overpowering or boomy like some bass head cans, I personally love the bass on these but they definitely aren't for people looking for a strong or imposing bass. Other than that the other instruments sounded great, the piano was clear and sounded similar to being in a room with a piano, I think what I found with these headphones is everything sounded exactly as it should.
 
SOAD......all of it..........I tend to really like this band
The first thing I noticed was the guitar sound, I could hear not only the sound of the guitar coming through the amp but also the sound of the guitar being played, strings being pressed against frets, picks strumming the strings, similar to how being in a room with a guitarist would sound. The drums had a nice oomph to them which was great, it reminded me of the drum sound I got when listening to a large speaker system rather than a pair of headphones. Its really a great sounding pair of headphones. The bass on tracks like Mr. Jack sounded clear and precise whereas on tracks like Streamline the bass sounded heavy and distorted giving each track its own unique tone instead of muddying all bass tones together.
 
Infected mushroom "friends on mushrooms"
I actually really like these headphones for infected mushroom because they make it easier to differentiate live bass from synth bass, one of the pros of EDM is if the track is programmed to sound open it will sound very open with these headphones. A lot of these tracks take advantage of the large soundstage these headphones have. These headphones definitely weren't designed with EDM as an intention but they do a good job so bravo to AKG
 
Miles Davis "kind of blue"
Bass sounds incredible, especially for something recorded decades ago. You can hear the bass throughout the track even as more instruments are layered on. Although it doesn't sound quite as clear and precise as Serj tankians "Jazziz Christ" I believe that has more to do with 60 years in technological advancements in recording equipment. The brass sounded wonderful and yet again just reminds me of being in a room with the instrument, a very large, open, room. I've listened to lots of closed backs and something about these headphones is different, it feels a lot closer to listening through a large speaker set in a big open room and less like listening to a pair of headphones, yet at the same time it gives the very immersive feeling of listening through headphones.
 
Jaco Pastorius
Just bass and piano galore, the harmonics sound incredible and the piano is beautiful and clear.
 
Lara Ruggles "snowflake"
Now I admit, I only have this track because it came with my DAP (sony NWZA17, wow they have got to come up with easier names), however, after listening to the track many times I'm probably going to end up getting the full album. The piano is perfect, it is absolutely perfect. Crystal clear, amazing sound, it's just beautiful. The vocals rang, there was power in her voice, you could hear all the slight nuances and subtleties that go with each individuals unique voice.
 
Okay I've rambled enough and I'm running out of adjectives in my active vocabulary to describe sound so I'm gonna end it here. These are absolutely fantastic headphones, I love the sound signature and the huge soundstage, these are super open and just sound beautiful with whatever you listen to (note: bad source=bad sound, you put good in, you get good out, I wouldn't recommend any sound files below 320Kbps, and I also wouldn't recommend generally poorly recorded albums, so maybe old punk fans wouldn't like it, it catches all the imperfections so just beware). I love these headphones and can't get enough of them, I've even been sleeping with them on sometimes (I guess thats a statement to their comfort). They're just amazing and for 200$ I cannot emphasize enough how much of a must buy they are. 

I'm a sort of an amateur in the audiophile world, however, after owning these headphones and pairing them with a good-ish amp (Aune T1 MK2), my not so expert opinion says that these are a pretty killer pair of headphones for the price (~$200 on Massdrop). They sound great, having a strong bass, smooth mids, and a clear but not over pronounced high range. Their comfort is greater than all headphones that I've tried before (given, that is a pretty selected range including most Bose headphones, some Sony, and a few Sennheisers). Only possible complaint is that they're built out of plastic, and are therefore more prone to breakage. Compared to HD280s (~$100), these are quite a steal for only double the price of the Sennheisers. Sorry for the poor quality review, I simply don't know how to describe these in as much detail as others can, however, I hope this short and sweet response is easier to digest for the new-ish headphone enthusiast.

 
The AKG K7xx is one of the most popular headphones around right now.  In this review you'll see some explanations as to why that is, and how it stacks up to a revered classic in the Beyerdynamic DT 880 Pro.
 
I am a 21 year old audiophile who sticks to headphones primarily.  So my impressions may differ from many of yours due to my age.  I'm not nearly as treble sensitive as most audiophiles.  Throughout my childhood me and one of my brothers dabbled quite a bit in acoustic music reproduction (him more so), although these days I just listen.  I had owned the Beyerdynamic DT 880 Pro for several months leading up to this review, so the K7xx is the more recent addition.
 
When it comes to headphone performance, transparency is of utmost importance to me, but I also prefer a highly detailed and three dimensional sound, and neutral tonality although I am open to some slight deviation from true neutrality.  I want a (mostly) true to life sound, and I demand accurate representation of acoustic instruments of all kinds, and I also demand engaging vocals.  I am partial to electrostatic headphones.  For reference, the best headphone I've ever heard in my opinion is the Stax SR-009.
 
Both the K7xx and DT 880 Pro (250 Ohm) were tested with my upgraded Maverick Audio Tubemagic D1 (swapped both opamps for LT1364s) which served as the DAC and amplifier.  This is a slightly smooth sounding device, especially with the opamp changes.  It is the older version of the D1, although from what I gather the newer one isn't much different and both are rated for 1W into 32 Ohm.  The D1 was connected to my computer via optical TOSLINK, and Foobar2000 with ASIO4ALL drivers was used for media playback.  I did my best to volume match both headphones although it is worth noting that on this amp, the DT 880 Pro can sound somewhat distorted at lower volume levels.  I generally listen at much lower volume levels than others, so distortion due to driving them too loudly was not a problem.
 
A variety of music was tested; from sub 320 Kb/s MP3 to high bitrate uncompressed FLAC.  Genres tested include classical/orchestral, metal (prog and melodeath), rock (mostly acoustic), and a small amount of electronica mostly for testing purposes (electronica is not something I typically listen to).  Both headphones were burned in for this test.
 
So, let's get right into it.
 
The build quality between both headphones is several leagues apart.  The K7xx is pretty much all plastic, the exceptions being the obvious (pads and suspension headband strap).  Even the grills are plastic, which I didn't think was a thing anymore.  Pictures are deceiving, it's not as sturdy as it looks.  
 
It is lighter than the DT 880 and significantly wider.  The ear cups are huge in comparison, and as a result the pads are larger in diameter.  The pads are memory foam, the suspension headband strap is leather which is a rarity among $200 headphones (or even sub $1000 headphones).  It features a straight, detachable cable unlike the DT 880 Pro, although the cable retains a small amount of bending.  The cable terminates with a gold plated 3.5mm jack, with a 6.35mm adapter screwed on.  The cable's plug-in design is sturdy and easy to use, just keep in mind it's very stiff to push in, but once it's in it's not going anywhere.
 
The Beyerdynamic DT 880 Pro on the other hand is almost all metal, except for the black part on the ear cups which is solid plastic (seemingly thicker and sturdier plastic).  It is semi-open opposed to the fully open K7xx.  The pads are very soft velour, softer than the K7xx's memory foam pads but also smaller in circumference and diameter.  The headband is thickly wrapped in pleather.  The DT 880 makes the K7xx feel like a toy.  However, the DT 880's cable is fixed and coiled, although also thicker than that of the K7xx.  Like the K7xx, the cable terminates with a 3.5mm jack and 6.35mm adapter.
 
Both headphones lack portability.  They don't fold much at all.  The DT 880's ear cups swivel a bit more.  It's worth noting that every K7xx is serialized (on the inner left side), although the DT 880 has its serial number on the box.  In conclusion, the K7xx is pretty flimsy compared to the tank-like DT 880, which is better built than numerous $1000+ headphones.
 
Winner: Beyerdynamic DT 880 Pro by a landslide.
 
 
 
Both headphones have a reputation of being comfortable.  The K7xx's pads are larger and deeper, although still not as deep as I like.  The DT 880's pads are slightly softer, but the K7xx's pads are so soft so that it's not a problem.  Furthermore, the K7xx has less clamp and less weight, so it's lighter than the DT 880 Pro in every way.
 
The K7xx has an auto-adjust suspension headband.  The headstrap is leather and not bumpy like other AKG models.  It's installed on rails so to speak so that it slides up, increasing the size of the headphone, depending on how large your head is.  So the K7xx should fit pretty much any grown man well.  However, due to its very wide design, it is not a good fit for many women or younger teenagers.
 
The DT 880 Pro's headband has a more typical adjustment system; the user must pull the headband up on each side.  There are small notches on the frame, so that the adjustment sticks, although it's not a belt loop system which I feel is more reliable.  The DT 880 is a lot smaller on my head than the K7xx.  Those with larger heads will find the DT 880 to be too small and too tight, but on the other hand it can fit most women and younger teenagers well unlike the K7xx.  So we have a sharp contrast here.  Big (headed) guys ought to avoid the DT 880 for comfort problems alone.
 
For me, both headphones are comfortable but the K7xx takes the cake.  The DT 880's ear pads are too shallow and squish my ears slightly, while the K7xx has much larger pads that are a bit deeper, making it more comfortable.  Suspension headband is the way to go for comfort; the DT 880 is already light but the K7xx is a feather.  Less clamp means the K7xx won't be fatiguing for almost everyone.  The K7xx is more comfortable to me, and it would be more comfortable for most of you.
 
Winner: AKG K7xx.
 
Since sound quality is a vague term, I'll be breaking this category down into many subcategories, and try to declare a winner for each one.  I won't attempt to declare an overall winner, since there really isn't one here.  Both headphones have their own strengths and weaknesses.  If I was comparing the Beyer T1 to the DT 880 then that's a different story, since I feel the T1 is a clear cut overall winner, but for this comparison the K7xx and DT 880 are pretty close in overall performance, and it boils down to preferences and priorities.
 
 
I thought I would comment on this.  The Beyerdynamic DT 880 Pro is a semi-open headphone, not a fully open headphone like the K7xx.  Despite this, it provides next to no isolation.  It lets as much sound in as a fully open headphone.  However, it leaks noticeably less sound, which can be useful to some.
Transparency is extremely important to me.  It mostly refers to clarity; a sound free of grain and interference so that nothing is between me and the music.  Both headphones are pretty much equal in this regard, and are no more transparent than my previous Audio Technica ATH-A900X.  So, with regard to high quality Mid-Fi headphones, the K7xx and DT 880 seem to be about equal to most others.  That is to say, neither are impressively transparent.  My old little electret Stax SR-30 is more transparent than both of them.  I certainly crave more transparency than what either headphone has to offer.
 
Winner: None, it's a tie.
 
This category isn't going to have a winner, I'll just describe the tonality of each.
 

1. AKG K7xx - Close to neutral, although slightly mid centric with a hint of added warmth.  The mids tend to overtake the treble slightly, but it's far from veiled or lacking in treble extension.  It sounds somewhat smooth, but not blurred and not as smooth as say the Sennheiser HD 600 or HD 650.
2. Beyerdynamic DT 880 Pro - Very neutral throughout, but much more "sharp" sounding than the smoother K7xx.  Treble is overall more forward compared to the K7xx.

 
The DT 880 is a great "palette cleanser" for its neutrality.  If your brain is used to a more colored sound, the DT 880 is good for erasing that and getting your brain used to a neutral sound.  Great for evaluating multiple headphones.
 
The DT 880 is known for the detail it provides, but to my surprise the K7xx is the winner here.  Despite being smoother sounding, the K7xx is more detailed.  This is largely due to the faster decay which I'll talk about in a bit.  The DT 880 sounding sharper is almost like it wants to provide the illusion of being highly detailed, but in fact there are far more detailed headphones out there.  Between the two, they are pretty close but the K7xx obviously has the edge here.
 
Winner: AKG K7xx
 
I may as well go into this now since I mentioned it already.  The K7xx's decay is faster and brings out more detail, and can make the background sound blacker.  However, it also leads to it sounding a bit more dry than the DT 880, which is most noticeable in rock and electronica.  It also causes me to reach for the DT 880 first for rock and electronica, and it's a big reason as to why I reach for the K7xx first for larger classical ensembles.  The faster but dryer decay of the K7xx ought to make it hard to choose one for faster, aggressive music since it's a compromise.
 
Winner: AKG K7xx
Both have similar bass quantity although the K7xx has a bit more in vocals (most noticeable in male vocals obviously).  They have very similar quality too, with regards to body/fullness and tightness/control.  The DT 880 Pro's bass extends down to right about 20 Hz to my ears, while the K7xx is super close but a tiny bit less extended.  This was tested using the bass test listed in the link at the bottom of the page.  In addition, the DT 880 Pro has a little bit more bass impact/slam, but both have very little, and note I've never bass modded my K7xx.  Neither are basshead cans, they're meant to be more accurate.  The bass is pretty accurate on both, so ultimately the superior extension crowns the DT 880 here.
 
One thing of note is that the DT 880's bass can sound very harsh and shrill on some really bad recordings, like its treble.  Everyone knows its treble can sound this way depending on the recording, but the bass sounding this way took me by surprise.  The bass never gets like this on the K7xx.  This is more of a fault of the music recording than the headphone in my opinion.
 
Quantity: A tiny bit more impact/slam with the DT 880 Pro, a tiny bit more forwardness/presence in vocals with the K7xx, otherwise a tie.
Quality: DT 880 Pro wins slightly in extension, otherwise it's a tie.
 
Mid range performance is extremely important to me, as it is for most of us.  Again, both headphones perform similarly here overall.  The K7xx has a tiny bit more warmth; hardly noticeable unless you go back and forth between each headphone like I did.  Still, it's not enough warmth to classify the K7xx as a warm sounding headphone, at least not on my Maverick Audio Tubemagic D1.
 
The upper mid range sounds a bit more linear on the DT 880 to my ears.  I think this has to do with a peak at the very top of the mid range and bottom of the treble on the K7xx.  It can make the transition between upper mids and lower treble sound a bit less authentic and somewhat uneven compared to the DT 880.  
 
But aside from this, the mid range performance is close, with the K7xx sounding a tad more dry and detailed because of its general characteristics.  Interestingly enough, on some tracks the K7xx puts acoustic instruments somewhat in front of vocals, but the DT 880 is always consistent with vocals being a tiny bit more forward than the instruments.  Also worth noting is that a few times, when a female vocalist is singing and a guitar is playing at the same time, the two overlap too much on the K7xx and it becomes very hard to focus on the guitar.
 
Ultimately, the more linear upper mid range of the DT 880 led to my decision here.  Although owning the two made me appreciate the hint of warmth provided by the K7xx.
 
Winner: Beyerdynamic DT 880 Pro
 
In my opinion, the vast majority of headphones have an imperfect treble presentation.  In fact, the only headphone I've heard with what I consider to be a flawless treble presentation is the Stax SR-009.  I think treble is just something electrostats tend to do better than non-electrostats, although the HiFiMan HE1000's treble sounded very well articulated, more than any other non-electrostat.  But I digress.
 
The K7xx does not want to overwhelm you with treble.  As such, it's usually slightly behind the mid range, but without being strongly recessed and without being rolled off.  Using the treble test linked to at the bottom of the page, I can hear the treble extend to around 19 KHz, which seems to be the limit of my hearing.
 
Likewise, the DT 880 Pro's treble extends to 19 KHz, further showing where my hearing limit is.  The DT 880's treble is overall more forward, and the DT 880's general sharper sounding characteristics are noticeable in the treble presentation.  As a result, the DT 880 is less forgiving with bad recordings.  The K7xx is not perfectly forgiving and can still sound slightly harsh and sibilant, but usually not as harsh as the DT 880 on some awful recordings.
 
Despite the overall more forward treble on the DT 880, it is the K7xx that reached the record high "peakiness" between the two.  I'm less treble sensitive than many other audiophiles (I can handle the DT 880's treble on anything), but the K7xx at its worst is actually piercing for my ears and too much.  I've only heard it sound like this once or twice and I don't remember which tracks specifically, but I think it was a poorly recorded classical track.
 
Both headphones sound about equally airy.  That is to say, neither are particularly airy.
 
The DT 880's treble sounds more linear to my ears.  The K7xx seems to have some peaks and/or dips that make it sound less natural at times.  The treble on both overall lacks the body and realism you'll hear on top tier electrostats.  Both have a flawed treble presentation, but the K7xx is more flawed for being less linear in my opinion.
 
Quantity: DT 880 Pro overall more forward, although the K7xx at its worst was more piercing than the DT 880 at its worst.
Quality: DT 880 is more sharp, but overall cleaner and more linear, so the DT 880 wins here.
Sibilance: Somewhat present on certain terrible recordings for both.
 
Both the K7xx and DT 880 are known for providing an open sounding, above average sound stage.  However, I was never impressed with the DT 880's sound stage.  It's not bad, but it's a far cry from its big brother, the T1.  I was always intrigued by the sound stage reputation of the AKG K7 series, and the K7xx does not disappoint.  It is noticeably wider, deeper, and taller than that of the DT 880.  I really like a big, three dimensional sound stage, and the K7xx actually satisfies me in this regard unlike the DT 880 Pro.  It is very evident when playing large ensembles.  The DT 880 has decent width and some sense of depth, but the K7xx handily bests it in both regards.
 
Too bad the vast majority of modern music is poorly recorded and doesn't demonstrate the sound stage performance of good headphones like the K7xx very well.  The superior sound stage of the K7xx is also very noticeable in gaming, so the K7xx has definitely taken over as my new gaming headphone for the better immersion and positional awareness it provides.
 
Winner: AKG K7xx
 
Truth be told, the DT 880's imaging never impressed me.  It isn't bad, it's just not great or mind blowing like its big brother, the T1.  Of course, the T1 is also significantly more expensive so that's expected.  The K7xx has superior imaging overall, taking advantage of its larger sound stage and mapping instruments and sounds all around it.  I don't consider the K7xx to be lacking a well defined center stage either.
 
But I do have to mention the overlapping of female vocals and guitars once again.  It doesn't happen always, but sometimes it can be hard to define guitar on the K7xx when a female vocalist is singing over it.  The DT 880 doesn't have this issue.  Still, it's clear to me which one wins overall with regard to imaging.
 
Winner: AKG K7xx
 
 
I was hoping one of these headphones would be clearly superior to the other in most areas, so that I could sell one and downsize, but this did not happen.  I'll have to keep both until I buy the Stax SR-L700, and even then I might keep the K7xx for gaming due to its phenomenal sound stage.
 
Both headphones are equally lacking in transparency, while the DT 880 Pro is the more neutral of the two and the K7xx is more detailed and three dimensional.  The DT 880 is less forgiving, but has a cleaner treble presentation despite sounding sharper.  The K7xx sounds more smooth, but needs parametric EQ more than the DT 880 (I have not done this yet) due to some peaks and dips in the treble region and perhaps upper mid range.  The DT 880 Pro strikes me as slightly more well rounded, due to its more linear tuning.
 
Both headphones are very comfortable, although the K7xx takes the lead here and it would prove more comfortable to most of other audiophiles I believe.  But the DT 880 stomps the K7xx with regard to build quality.
 
Curiously enough, owning both of these headphones has made me less satisfied with both of them.  I really want to get that Stax setup now...
 
Instrument Specific Notes
 
I thought I'd list specific kinds of instruments with which one headphone is noticeably better than the other.  Any instrument type not listed just means the two headphones perform too closely for me to declare one better than the other.
 

1. Piano - AKG K7xx is more realistic here, offering slightly better detail and texture and body.
2. Horns - The DT 880 Pro is shockingly more realistic here.  Maybe it's my amp but horns are just not convincing on the K7xx.
3. Drums - Both headphones are close, but the superior bass extension of the DT 880 Pro makes it better at portraying drums.  Then there's the fact that the DT 880 has a tiny bit more bass slam/impact, although this isn't really significant.
4. Electronic Instruments - DT 880 wins, the dryness of the K7xx is not ideal here.

 
Genre Recommendations
 

1. AKG K7xx - Classical/orchestral, should also be great for pop, although it's not particularly bad for any genre either.
2. Beyerdynamic DT 880 Pro - Anything and everything.

 
The following website provided me with bass and treble extension tests:
 
http://www.audiocheck.net/soundtests_headphones.php

==Introduction==

 
I would like to thank the Head-Fi Massdrop staff and AKG for producing such a good pair of headphones. This pair has honestly been one of the best cures for upgrade-itis I have had in a long while and I think that it will be a nice ending to the long story of the AKG K7-series driver as I think AKG decided to do this because the driver is nearing the end of its life cycle. 

 

This review should of course be taken as a grain of salt as it is my opinion and only my opinion. I have past experience with quite a few cans and IEMs before. I personally own or have owned these cans and IEMs (to the best of my knowledge):


 

1. Sennheiser HD25 Aluminium 25th Anniversary Limited Edition
2. Sennheiser HD424
3. M-Audio Q40
4. Denon AH-D2000
5. NAD VISO HP50
6. Aedle VK-1
7. Beyerdynamic DTX-101iE
8. Monster Turbine Pro Gold
9. ADL EH-008
10. Koss Sportapro
11. Other odd vintage cans

 
As for the backstory behind these cans, I bought the AKG K7xx when I read the description for the drop for it on Massdrop.com touting these pair of cans to basically be a warmer, bassier AKG K702 Annie back around November. As I have already tried various AKG cans in the past and disliked many of them because of the lack of bass, the overly bright tilt and the oh-so-dreadful headband bumps that most of the mid-tier AKG cans seem to possess, I thought to myself that this would be just the ticket to satisfy my desires and jumped right onto the drop, to the displeasure of my wallet and the absolute joy of my ears.

 

==Aesthetics==

Packaging and Accessories

 
These headphones arrived much later in typical Massdrop fashion in a rather typical box with all the usual labelling on it advertising these cans.  (As most people say, you forget that you’ve bought something on Massdrop and then whatever you’ve bought comes as a pleasant surprise much later!) The packaging these headphones come in is, for lack of a better word, minimal – just enough to keep them safe and make them look pretty but nothing else. When I opened it to have a look, the cans seemed to be quite lonely as it comes with absolutely no accessories to accompany it, apart from a ¼-inch adapter. Well, I suppose that means that my attention will be focused on the cans, it seems. I just wish they came with a carrying case.
 

Design and Build

The AKG K7xx Massdrop 1st Edition is a pair of open-backed headphones co-designed by Massdrop and AKG and are the first batch of a limited run of 6000 headphones. For a pair of $200 headphones, they have a fairly typical build for this price point and are mainly made out of plastic with a bit of metal and real leather used for the headband. They obviously won’t survive a direct hit from a nuclear strike but they should last fairly long under daily use. Plastic obviously means that they feel slightly cheaper but this also contributes to its very light 235 grams of mass which is very good comfort-wise (as I will mention later).

 

They have a really cool stealth black colour scheme which deserves props to AKG for completing the cycle of colour schemes they used starting with white for the original AKG K701 and ending with black for this pair of cans. They have a single-entry configuration for its 3m rubber-coated cable which, while nothing special, does the job with fine fashion. One end is terminated in a 3.5mm jack which accepts a 3.5mm to 6.3mm adapter provided by AKG and the other end is terminated with a 3-pin mini-XLR jack. Left and right sides are labelled on the outside of the headband and is fairly easily located. The ear-cups are free to swivel a small amount in any direction but do not fold flat as they are designed for desktop listening.

 

Comfort and Isolation

Firstly, these are open-backed headphones. Therefore, isolation is irrelevant in this review as they let in almost any background sound and thus isn’t fair to properly judge. However, I do have to say that the leakage from this pair of cans is surprisingly minimal considering its nature and I do have to say that I’m impressed.


Comfort, on the other hand, gets a very big thumbs up for me because I tend to be fairly picky when it comes to this. The pads, while not being the deepest, are adequate enough for my ears to nestle in the cups for a few hours without any issues. 

 

The only gripe I have with them is how the tips of my ears touch the inside and how this causes some pain after a few hours, but by then I should be taking a break anyways so this is a fairly minor issue. The headband, like I mentioned previously, is made of real leather, which is a nice touch. The main plus for me, however, is the fact that they have none of the atrociously painful headband bumps that early AKG K7-series headphones had which means that the headband rests comfortably on my head. Clamp is also fairly minimal, being just enough to keep these on my head as long as I don’t start headbanging but not nearly enough to hurt the area around my ears.

 

The only other issue I have is with the elastic headband suspension system. It’s been fine for the few months I’ve been using this pair of headphones but I’m somewhat worried that they’ll lose elasticity over the years (especially since there have been reports of this happening with other AKG cans) but this also means that the entire system is self-adjusting, which is perfect for my OCD self as I just have to put them on without worrying about setting the headband to be exactly this much distance apart.

 

==Sound==

 

Equipment and Burn-in

The equipment I used was: Windows laptop (running Foobar 2000) > AMB Gamma2 > Headamp Gilmore Lite V2, with no EQ used. These headphones have at least a few months of usage and I haven't detected (or don’t remember) any change within the first 100 hours or so of using them. However, I did not burn them in at all and  instead used them straight out of the box.

 

Bass

As this is an open-backed headphone, extension will of course not be as great as a closed-back headphone. However I was pleasantly surprised to hear that these reach surprisingly low with good clarity and texture. There isn’t the biggest amount of bass, but it’s definitely enough for every genre of music I listen to. It’s punchy and quick when it needs to be and never overwhelms the sound signature.

 

When it comes to orchestral pieces, sub bass is extremely important for reproducing the feel of the piece. I’m happy to say that this pair of cans have enough to make for an enjoyable listening experience. Compared to the HD650, the bass is far quicker and actually works for electronic music unlike the HD650.
 

Midrange

The mid-range of these headphones take center stage here. It’s very clear and natural-sounding but also a little warm to give vocals and instruments a little extra oomph to make them sound majestic and lively, unlike most AKG cans in this price range. There isn’t a music piece I’ve listened to that sounds artificial or unnatural with these headphones so far, which greatly impresses me as many other headphones I’ve listened to simply don’t work with specific genres. Everything is articulate and very well-defined and is most similar to a window into the recording. It’s not overly lush and rich but not overly thin and cold either and even subtle distortions in the music can be heard as a result of mastering errors.

 

Treble

This treble can best be described as neutral to slightly bright, like a cool sip of water in a summer’s day. It’s very well-extended, precise and linear with some subtle lower-treble emphasis which is fairly typical of an AKG can. However, this emphasis is far less pronounced than most other AKG cans and for that I am grateful as I am sensitive to nasty treble spikes. It’s also very resolving, able to pick up a lot of detail in recordings and can be described as rather crisp and clear. However, despite the focus on detail of these headphones, the treble never gets too bright as long as the recording is good quality.

 

Soundstage/Presentation

Here we go, the famous AKG soundstage that the company’s headphones are known for having. As expected, the AKG K7xx does not disappoint, offering a spacious, wide, high and deep soundstage with excellent positioning and clarity. Every instrument has its own place and the soundstage is so realistic that oftentimes I will think that a sound in the music came from real life – trust me, it’s a confusing feeling when this happens and it’s a good thing!
 
The overall sound signature of the K7xx is very natural and lifelike. The frequency response for the most part seems to be fairly neutral and most importantly, natural. This pair of cans especially excels with live recordings but can handle most any genre you throw at it and brings the focus of the listener, not the sound signature of the AKG K7xx like some headphones do. Timbre and tonal balance is both excellent and overall these pair of cans seem to be somewhat like a pair of speakers. This also means that they are not forgiving of poor-quality source files which can be a good or bad thing depending on your choice of music.
 

Update: The Bass Port Mod

After doing the fairly simplistic bass port mod (the details of which are detailed here), the bass quantity improved by a noticeable amount without bleeding into the mids. They're now an excellent pair of cans for even those genres which require a heavy-handed approach to the bass section while still being great at what they were originally good at. Anyways, I like these cans even more now, but keep in mind that the mod is not for everyone, especially not for those who prefer a linear bass section.


 

==Conclusion==

 
The AKG K7xx is probably the best $200 (excluding the $30 shipping) purchase of my life so far. I have been happy with them for over 6 months and I am sure I will be happy with them for many years to come. I prefer it over a lot of the other headphones I’ve auditioned, including its fellow brethren, the Beyer cans, the Sennheiser HD650 and many more. The value is simply insane and I think that its AKG’s best value pair of cans they’ve made in a while.

 

Some things that AKG could improve on, although I don't see much, is to perhaps include a carrying case for these wonderful headphones as it would be a shame if they broke. I would also love it if they used a 4-pin XLR instead of a 3-pin XLR connector for the cable. It's a good thing that they cost only $200 though as this helps to justify the lack of accessories. However, the bass port being closed up is in my opinion a strange decision. I have a feeling that AKG planned to leave the port open but closed it up at a later time for whatever reason, the likes of which completely defeat my mind as I greatly prefer these cans with the port open.

 

 

==Specs==

I did have to get a replacement because the original set's left channel stopped working after a month or so, but massdrop was very accommodating/helpful and i got a new setup within a month. Amp not really necessary but i recommend it because these enjoy the extra juice and are best-of-class for the pricepoint.  They are large,classy and will blow you away unless you have a grand or more to step up to end-game.

AKG K7xx Massdrop 1st Edition Headphone Review:
 

 
Intro:
 

 
The new AKG K7xx is the result of a joint venture between AKG and Massdrop. Based on the limited 65th anniversary edition of the K702 released in 2012, the AKG K7xx is made by AKG and specially configured by Massdrop. They are a Massdrop-exclusive item and not currently available from AKG.
 
Fun Fact: A total of 6,000 AKG K7xx 1st Edition headphones were produced. All the 1st Edition models have been already sold, and no more 1st Edition drops will occur. No official word on subsequent non-1st edition releases, but click “Request” at this link to vote on bringing it back. Credit to Danny, Will, and the rest of the Massdrop team for organizing the first drop.
 
***Update on 5/25/15: A second production run of Limited Edition K7xx (non-1st edition) is currently available on Massdrop and will ship 6/26/15***
 

Image of the packaging (Front View)
 

Image of the packaging (Side View)
 
Tech: The AKG K7xx is an open-back, over-ear pair of headphones with 45mm diameter dynamic transducers. It uses AKG’s patented varimotion two-layer diaphragm and unique flat-wire voice coil. Its frequency response ranges from 10 Hz to 39.8 kHz. The Massdrop price for the K7xx was $199.99 with free domestic shipping and a 2-year warranty included.
 

AKG K7xx (Side View)
 

AKG K7xx (Front View)
 
Design & Comfort:

 
The K7xx has the traditional AKG design and styling with their patented self-adjusting suspension system to ensure a comfortable fit. It features a new all-black stealth color scheme with grey and white lettering. I really appreciate the new subtle professional look without any color accents. Left and right sides are labelled on the outside curvature where the headband connects. The unique 6-digit serial number denoting the first edition headphones is discretely located on the interior left-side near the headband while the right side features the Massdrop logo. Like the majority of other AKG headphones, the K7xx is manufactured in China. Primarily constructed with plastic, the headphones are extremely light-weight with the official weight is quoted at 235 grams. I measured my pair without the cable to be 290 grams on my small kitchen scale. Included accessories are a straight 9.8 ft detachable cable (mini-xlr to 1/8" terminations) and an included screw-on 1/4" adapter.
 

 
Thoughtful upgrades (from the first generation AKG 7-series) include the usage of genuine leather headband without any annoying bumps on the bottom surface and velour-covered memory foam earpads. I measured the interior of the earpads to have a 70mm diameter with 24mm depth. The depth of the earpads does compress down quite a bit when worn, so it is possible to experience slight discomfort from the tips of your ears touching the inside of the driver after prolonged usage. The earcups have a ball-in-socket type swivel mechanism that allow for subtle adjustments to accommodate various head shapes. The earcups can swivel 20 degrees in any direction. Similar to many other open over-ear headphones currently on the market, the K7xx earcups do not fold flat as they are designed for non-portable usage. The low weight, large earcup diameter, and premium materials where your head touches the headphone makes for an extremely comfortable experience even for multiple-hour long listening sessions.
 

 
While the K7xx does not have an particularly exotric or luxurious feel, the overall build quality and design is very competitive for its price point. Very beautiful professional-looking pair of headphones with quite durable construction and universal appeal.
 

 
Sound Quality:
 
The K7xx’s overall sound signature is exceptionally well-balanced sound signature without any noticeable emphasis or recession throughout its frequency response. From extensive listening tests with music and test tones, I did detected an extremely subtle midbass emphasis along with slight upper midrange and treble accentuation. The word emphasis is actually a bit of an overstatement as the subtleties to the tuning was barely detectable with frequency response sweeps. I do feel that the K7xx’s overall presentation appears very realistic and natural with recordings of live music. I would personally consider this sound signature to be a very close-to-perfect representation of neutral. The pre-recorded changes in frequency response emphasis of the musical tracks dedicates where your focus goes, not the K7xx’s sound signature. To my ears, the K7xx has an extremely life-like representation of music. With an accurate tonal balance and authentic timbre, the K7xx sounds to be the definition of a transparent pair of headphones to my ears.
 
Treble has enough brightness to give a nice brilliant sheen to the notes without being too aggressive. Extremely extended treble frequency response into the upper register. Do note that my hearing only goes up to 18kHz. During a treble frequency sweep, the entire treble response was extremely linear to my ears. This type of linear treble presentation is often called ‘delicate.’ Very clear, airy, and crisp treble presentation. Its highly-resolving abilities are capable of picking up extremely low-level micro-detail. Adds a very nice breathy touch in the upper mids and treble. I could easily catch the almost imperceptible breath sounds of the woodwind musicians inhaling and exhaling within the composition. I could also regularly recognize the complete breathing patterns and appreciate the breath control of female vocalists. The presence range of 4 kHz to 6 kHz responsible for intimacy is not artificially over-emphasized or recessed, but inline with the rest of the treble response. The K7xx does not have an overly intimate presentation at all, favoring an analytical detail-focused approach instead. Great sense of treble energy allows for these headphones to really shine at accurately portraying the high registers without any excessive edginess.
 
The midrange is exceptionally well-defined and articulate. The subtle nuances between the vocals and instrumental interactions are revealed. No extra sense of richness or lushness to the sound signature caused by euphonic distortion. No tinniness or thinness either, but a good sense of fullness without any bloat. Instrumental timbre and tone exceptionally well-represented. Subtle deviations in pitch and texture is also quite clear. Very satisfying sense of balance in this region. The quiet low level detail is easily audible to the point that even minute distortions with some of the older classical tracks due to poor mastering can be quickly identified. These headphones are not as forgiving with poor source files as they are extremely revealing. If there is sibilance, distortion, or noise in your source files, these headphones will not glaze over source flaws and try to hide them. This can cause a shockingly obvious discrepancy between the quality of lower bitrate files compared against 320kbps lossy, lossless compression, or CDs.
 
The K7xx has a gripping bass with a strong sense of control and sturdiness. No excessive bass reverb on the K7xx. The bass extension are excellent for a pair of dynamic headphones, but there is a subtle low sub-bass roll-off compared to high-quality orthodynamic headphones. The subtle linear mid-bass emphasis adds a pleasant touch of fullness to the sound signature. There is weight to the bass response, but it never feels overemphasized. There is enough impact to feel the rhythm, but it’s never stomping for your attention at the expensive of the mids and treble. The bass presentation is definitely not overly warm. It seems more akin to a moderately ‘cool’ presentation with the long curving subtly downward slope after 120 Hz. Very enjoyable bass response, but not an exciting seismic or visceral bass. Very even-tempered and even-keeled.
 
The soundstage and imaging of the K7xx is its most outstanding sound quality attribute. The instruments is presented with great focus. Exceptionally spacious with a very large equally-balanced sense of width and depth. Very good sense of height as well. Its soundstage can be spatially represented as a donut-shaped concert hall. This presentation with the horizontal plane being much taller than the vertical plane allows for an extremely realistic portrayal of sound stage. Imaging has a high level of precision that gives the distinctive feeling that every sound can be deftly localized within a few inches of its source. The hyperrealistic portrayal of soundstage and imaging of the K7xx caused me to instinctively turn my head to look at an exact position within the room whenever I got startled by an unexpected sound.
 
The K7xx has very excellent speed and control for a dynamic pair of headphones. Notes are presented tightly with a good sense of spacing. Transient response is excellent with short attack and decay times. The K7xx is not as fast as a few of the top tier orthodynamic headphones, but this is not noticeable until I did extensive direct side-by-side comparisons. Control over the micro and macro dynamics is top-notch with tiny or sudden changes in volume rendered flawlessly. The micro-detail and noise within the source are revealed with clarity and agility on the K7xx.
 
There is a good balance between an analytical/clinical presentation with organic presentation. I would be hesitant to characterize the K7xx as one or the other. If forced to choose, I would deem the K7xx to be more on the analytical spectrum with its presentation, but it does still capture strong sense of musical coherency throughout its frequency response that is very revealing of the textural changes. The defined hyper-detail retrieval coexists with a strong sense of musicality on the K7xx.
 
***Note: Please use this guide here if you are unfamiliar with any of the audiophile terms I used.***
<http://www.head-fi.org/a/describing-sound-a-glossary> (Credit: miceblue, warrenpchi, autoexec, ClieOS, and Gorthon)
 

K7xx on EBA-01 headphone stand (Front View)
 

K7xx on EBA-01 headphone stand (Angled View)
 

K7xx on EBA-01 headphone stand (Close-Up 1)
 

K7xx on EBA-01 headphone stand (Close-Up 2)
 


K7xx on EBA-01 headphone stand (Side View)
 
Measurements:
*******Important Notes*******

1. I wrote my sonic impressions prior to doing personal measurements.
2. Please note I am a relative amateur at measuring headphones. My personal measurements may not be as accurate as other sources. May update measurements as I run more trials. Any feedback or suggestions for improvement appreciated. Let me know if you spot any errors.
3. Measurement chain: Dell XPS m1530 with Windows 7 > ARTA Generates Sine Sweeps > Steinberg UR-22 USB Interface with Yamaha ASIO > Line Out > Oppo HA-2 Amplifier > headphones placed upon my own head (left ear being measured) > Pannasonic WM61-A Microphone > Steinberg UR-22 > Laptop > ARTA analysis
4. I used a Panasonic WM61-A microphone in my measurement set-up. The WM61-A does actually measure very flat until the upper treble range when calibrated. Its unequalized response should be flat within +/- 1.5 dB to 20 kHz. Frequency response curves are smoothed to 1/24 octave.
5. The dip in the 6kHz region is an artifact from the interaction from the mic placement with the shape of the ear folds. This artifact appears in all my measured frequency response curves via my current personal measurement set-up. The dip at 3 kHz in my measurements also appears in the Massdrop official measurements. The 3 kHz dip is not audible from my personal listening tests, most likely just the way an uncompensated raw graph will look.
6. You can NOT directly compare my personal measurements to other frequency response curves made by other people!!! There will be inherent discrepancies due to differences in measurement set-up, so comparing measurements from different sources is not reliable!!
7. For frequency response curve comparisons, I would recommend Tyll’s extensive database. Full list of his measurements found here. (credit: Tyll Hertsens at Innerfidelity)
8. Reference here for frequency response correlations to instruments and audiophile terms. (credit: Independent Recording Network)

***********************************
FR measurements by Other Sources (Remember not to directly compare measurements from different sources)

Above: The Official K7xx's Frequency Graph on Massdrop (link here)
 

Above: Tyll's AKG K7xx Measurements: source here
 
*****My Measurements*****

My Measurements, Trial #1: Pink Noise, Smoothing 1/24th
 

My Measurements, Trial #2: Pink Noise, Smoothing 1/24th
 

My Measurements, Trial #3: White Noise, Smoothing 1/24th
 
Personal comments on the my measured FR: While there is a slight 3dB bass boost measured (most prominent in the mid-bass region), I do not hear a significant bass emphasis when doing a test tone sweep. For open headphones, it is often desirable to have a subtle boost to the low end response to achieve a natural sound and hit the ideal target headphone response (which is not a flat line on the raw curve). I did not hear the dip at 3 kHz, most likely just the shape of uncompensated graphs. The 6 kHz dip is an artifact of my measuring set-up. Also, you can see the variation in the upper treble region from my repeated measurements; This is a common occurrence among all headphone measurements. The upper treble region is usually measured by taking the average of multiple trials with smoothing applied. The raw single trial data on the upper treble is not indicative of the headphone's performance.
 

Impulse Response
 

Frequency Response Curve Generated from the Impulse Response
 

Cumulative Spectrum Decay Plot Generated from the Impulse Response
 
Note: Feedback or suggestions on how to improve my measurements are welcome!
***Special thanks to hans030390 and Bluemonkeyflyer for all their helpful advice and tips when I was just starting out & learning about the measurement aspect of this hobby!!***
 
Direct Comparisons: (links take you to the head-fi product page of each model)
*******Important Notes*******

1. I am defining “mid-fi” as headphones that are not considered entry-level or flagships. Does not mean that its actual sonic performance is not high-fidelity. The overall mid-fi open over-ear headphone category usually ranges from $300-$700.
2. Please remember these are my own personal subjective impressions. YMMV!!!

*********************************
Against the ATH-M50x: Good reference point for a closed entry-level v-shaped portable.
The ATH-M50x sounds congested and suffocatingly closed-in during a direct comparison against the K7xx. Very prominent bass and treble emphasis with a recessed midrange on the M50x in comparison to the K7xx’s frequency response curve. Noticeable faster and tighter notes with better instrument separation on the K7xx. Much better imaging on the K7xx as well.
 
Against the PM-3: Mid-fi closed, portable planar magnetic with balanced tuning & outstanding performance, one of my personal favorites in this category
Biggest difference is that the K7xx has a much larger and spacious presentation compared to the PM-3's intimate presentation. The K7xx has a crisper, airy treble presence compared to the smooth treble presentation of the PM-3. Bass quantity is approximately the same. The PM-3’s have a subtle bit more sub-bass emphasis compared to the K7xx’s more mid-bass emphasis. Imaging is quite precise on the PM-3, but even better on the K7xx. The K7xx is less forgiving with poor sources than the PM-3.
Against the AKG K553 pro: Very capable mid-fi closed full-size pair of headphones based on the K550.
Similar tuning between the two models. The K553 has a warmer bass presence and more bass reverb due to its closed design. The K553 has a non-fatiguing treble tuning while the K7xx has more crispiness and airiness to the treble region. The K7xx also has sharper, better defined treble and improved overall clarity. Soundstage is larger and imaging more precise on the K7xx. The K7xx is less forgiving with poor sources than the K553.
Against the AKG Q701: Mid-fi dynamic open
The Q701 had a wider L-R soundstage but less depth and height. The Q701’s lateral soundstage seemed a bit too wide to my ears which detracted a bit from its realism. The K7xx’s soundstage is more akin to a donut with the same width and depth to its soundstage. The K7xx’s soundstage height is larger than the Q701. Note, I personally did not experience the ‘center hole’ phenomena with the Q701’s sound stage, but I can understand where those impressions come from. In terms of sound signature, the Q701 had a very sharp and bright treble-oriented sound signature while lacking in its bass response and presence. I considered the Q701 to be colored on the bright side of neutral. The Q701 sounded a bit artificial at times and can be a bit thin and tinny. I personally strongly prefer the K7xx’s sound signature and find it to sound more natural and realistic to my ear.
 
Against the Beyerdynamic DT880: Mid-fi dynamic semi-open (demo only, not direct comparison)
I don’t want to comment too in-depth here as I have only demoed these headphones and not owned them for significantly long periods of time. The DT880 is generally considered to be quite close to neutral, but I personally thought the DT880 had a tad bit of a subtly v-shaped interpretation of neutral. I found the DT880 to have a bit excessive brightness and treble energy for my tastes. I do remember being impressed by the DT880’s bass extension and bass quality. Still an outstanding pair of headphones with extremely high sound quality, especially at its price point. Most likely very similar overall technical abilities though I know that the Q701 had a larger soundstage than the DT880 from a direct comparison. I have a feeling that the K7xx also has a larger soundstage compared to the DT880, but cannot be sure without a direct comparison.
 
Against the Sennheiser HD600/HD650: Mid-fi dynamic open (demo only, not direct comparison)
Again I don’t want to comment too in-depth here as I have only demoed these headphones and not owned them for significantly long periods of time. In terms of overall obvious sound signature differences, I am comfortable saying that the HD600 does appear to have slightly less bass presence and treble energy compared to the K7xx while the HD650 also appears to have less treble with about the same or a bit more bass presence against the K7xx. Hard to specify exactly without a direct comparison. I did think the HD650 has a warm presentation, while I don’t get that feeling with the K7xx. I never had any issue with a Sennheiser veil, but the K7xx definitely does not have veiling of treble energy. K7xx is extremely airy without any inherent graininess or harshness. I do think all three of these headphones do provide a very close to neutral overall presentation and personal preference will determine which you will like the best. The most obvious sound quality difference beyond the differences in sound signature is that the K7xx has a faster transient response while the HD600 and HD650 are more laid-back and sound more relaxed. Soundstage and imaging also appears to better on the K7xx in my subjective estimation.
 
Against the HE-400 (rev4): Mid-fi orthodynamic open
The K7xx has a larger soundstage and more precise imaging. The HE-400 has faster transient response and more spacing between notes. The bass is more linear and extends deeper on the HE-400 for a weightier, more visceral bass presence. The K7xx has a subtle mid-bass emphasis and the K7xx’s sub-bass presence is not as noticeable compared to the HE-400. The HE-400 had an unique coloration consisting of an upper-mid recession with a treble spike. I personally greatly enjoyed the HE-400’s sound signature, but its overall tuning is not as neutral and balanced as the K7xx. IMO, the K7xx has better mids and treble while the HE-400’s greatest strength was its bass quality. The K7xx’s tuning is much more versatile with a wider range of genres than the HE-400 that can sometimes sound unnatural on certain tracks.
 
Against the Hifiman HE-560: Good reference point for flagship w/ a neutral clinical presentation.
The K7xx has a very similar neutral-oriented more clinical sound signature presentation as the HE-560. The HE-560 is a bit brighter with a deeper and more linear bass response. Bass notes do seem tighter than the HE-560 and better defined. Faster transient response on the HE-560. Soundstage is very close to call. I give the edge the the HE-560, but it is not by too much. Better detail retrieval and clarity on the HE-560.
Against the Audeze LCD-X: Another good flagship reference point (darker-presentation).
The K7xx does not share the darkness and specific colorations associated with the Audeze house sound. The LCD-X’s bass performance is a lot more satisfying than the K7xx with a more visceral presence and stronger weighty impact. Bass notes do not seem that much significantly tighter, I do think the bass texture and definition on the LCD-X is among the best within flagships and easily beats the K7xx. A bit faster transient response on the LCD-X, but very close to call. Soundstage is even harder to call here and it may be about even in my estimation. Differences in soundstage and imaging would be in inches, not feet.
 
More Comparisons: (links to my posts within head-fi threads)

1. The HE-560 vs LCD-X vs K7xx
2. Specific Song Analysis of differences between the HE-560 vs LCD-X vs K7xx (test track: Whispers In The Dark)

 
 
Amplification:
 
The AKG K7xx has a sensitivity of 105 dB/V and rated impedance of 62 ohms. This means to reach a 115dB (the volume of a loud rock concert), only 161 mW of power is required. Normal listening levels for headphones typically range from 60 dB to 95 dB. It is possible to reach normal listening volumes without any additional amplification with these headphones and I was able to reach more than adequate listening volumes with the K7xx driven directly out of the 3.5mm headphone jack on my Samsung Galaxy S5 smartphone.
 
I would personally recommend adding an amplifier capable of 50-200 mW RMS at 64 ohms to guarantee enough headroom for clean controlled performance during dynamic peaks. Do note that 200 mW is very excessive as the maximum input power for the AKG K7xx is 200 mW. That range will give more power than the required calculated amount. Keep in mind that there are many other factors beyond power ratings that determine an amplifier’s performance and pairing. The majority of dedicated headphone amplifiers on the market should be more than technically sufficient for the K7xx.
 
Reference for calculating power requirements: http://www.apexhifi.com/specs.html
Reference chart for the volume levels: http://www.gcaudio.com/resources/howtos/loudness.html
 
I tested the K7xx with quite a variety of amplifiers and dacs including the Resonessence Herus, Oppo HA-2, Schiit Lyr 2, Schiit Bifrost Uber, and Woo Audio WA7 with WA7tp. I would characterize the K7xx as quite transparent to external components, meaning they can pick up the subtle sonic characteristics of your external components. My personal favorite pairing out of my collection for the K7xx was the Lyr 2 hybrid tube amplifier and Bifrost dac for a warmer presentation but still very detailed sound. The HA-2 also was a good choice for providing a clean interpretation of the K7xx’s sound signature with minimal additional coloration.
 
Generally, the addition of an amplifier will provide improvements in soundstage, detail resolution, dynamic range, and speed for a cleaner, better controlled sound. There can be subtle sound signature changes with different amplifiers as well. I personally do think the sonic improvements with different amplifiers are generally quite subtle as long as the headphones are being adequately powered. I did notice the sonic performance of the K7xx scaling up with different components with its best technical performance out of my Schiit Lyr 2 + Bifrost stack.
 
I would recommend using an amplifier with the K7xx, but I do think most any amplifier will be sufficient. For people who enjoy a warmer, more relaxed sound, hybrid tube amplifiers can be a good choice. The budget entry option I used in the past was the Bravo V3. For people looking to keep the original sound signature of the K7xx, there are a variety of well-recommended solid-state amplifiers at various price points. Two popularly recommended entry-level solid state amplifier and dac combos are the JDS ODac+O2 amplifier and the Schiit Modi dac + Magni amplifier. I have found the HA-2 to be a great choice if you require the versatility of portable device that has multiple gain settings, bass boost feature, and smartphone battery charging features.
 
Value Judgment:
 
The K7xx offers an extremely competitive price point for the sound quality they provide. I personally cannot think of another $200 pair of headphones that match their technical prowess and has a such a well-balanced natural-sounding sound signature.
 
The K7xx competes directly against the classic well-respected $300-$700 mid-fi headphones from Sennheiser (HD600/HD650), Beyerdynamic (DT770/DT880/DT990), and from within AKG’s own line-up (K702 65th Anniversary Edition, K712 pro). The K7xx has among the best soundstaging abilities out of open headphones and should easy outperforms the majority of closed-back headphones currently available on the market up to the $700 price point in that department. Upgrading from an entry-level open or closed headphone to the K7xx will give you a quite noticeable improvement in sound quality that should relatively easy to appreciate (even without a direct comparison). The sound quality improvements jumping from the K7xx to the flagship headphones are much more subtle and you will be diving into the area of diminishing returns. Without a direct side-by-side comparison, it can be difficult to precisely pick out the exact technical performance differences between the K7xx against superior flagship models. The most obvious sonic improvements that flagships possess over the K7xx are faster transient response times, the removal of subtle graininess to the texture, and slight improvements to the overall clarity/detail resolution.
 
To put it into relative perspective, I am comfortable giving a personal relative estimate that the K7xx will give you at least 70-90% of the performance of the flagship models, while the K7xx can provide a 50-300% improvement in performance compared to entry-level headphones (all depending on the specific model of course). The K7xx still stays extremely competitive and evenly-matched against the best mid-fi offerings even up to the price range of $700.
 
These headphones are my personal top pick for the mid-fi open-back over-ear category not only in terms of performance/price ratio, but also overall sonic performance. Sound signature preferences can sway your personal pick among these headphones, but there is no denying the K7xx’s strong sonic capabilities.
 
Scoring: (the green bar ratings on the side seem to be an average of all review scores, this is my actual scoring)
Audio Quality: 9/10
Comfort: 8/10
Design: 9/10
Value: 10/10
Overall Rating: 5/5 - I do not give a 5/5 overall rating lightly. This is the only gear I own that I view to warrant a full score rating. The AKG K7xx's overall performance is extremely competitive without any significant flaws. The K7xx's performance per price point and overall value is unbeatable (in my experience, compared to all the headphones I have owned and demoed).
 
Conclusion:
 
Sound signature is very close to “audiophile-neutral” with a subtle linear bass elevation in the frequency response curve for a more natural sounding presentation. Soundstage and imaging capabilities are among the best in this category. Extremely fast speed for a dynamic headphone with great instrument separation. Extremely detailed and precise sound with a crispy airy treble, natural-bodied bass, and clean articulate midrange.
 
Greatest overall strength is its sonic performance per price value. Amazing audio performance that can go into the ring against flagships without being embarrassed for only $200. Greatest specific sonic strength is its soundstage and imaging abilities, which are among the best for open headphones. Detail retrieval is extremely excellent, picking up the most subtle changes in texture and very minute background sounds. Its frequency response tuning is very well-balanced and natural to my ears. Very versatile and will perform well with all genres of music. Will respond to EQ very well due to its balanced tuning.
 
Greatest con that I could find was the depth of the earpads. I do think a bit thicker earpads may nice as the memory foam compresses down after usage. This is an extreme minor fault. At their price point, there is really no other options that offer their combination of affordability and high-end sound quality. Second con is that they are not widely available and only available via time-limited drops from Massdrop. Final factors in determining if these headphones are suitable for you would be if you require noise isolation or if your music collection only consists of extremely low bitrate lossy files. The open-backed K7xx will leak sound in and out, and they are very highly resolving of micro-details, so they can be unforgiving with poor source files.
 
For aspiring audiophiles trying to find their first pair of ‘audiophile-oriented’ headphones with a clean uncolored sound signature as well as veteran audiophiles searching for a pair of reference-quality headphones with a high performance/price ratio to complement their existing collection, I would highly recommend the AKG K7xx.
 
Definitely an extremely competitive offering against everything else currently on the market from a sound quality to price perspective! A well-balanced, clean, uncolored sound signature with precise micro-detail resolution and best-in-class sound stage!!
 
I deem the AKG K7xx to be "Stealthy Cold-Blooded Giant Killers" as they currently are a difficult-to-acquire pair of headphones. Cloaked with a sleek black look that blends into the shadows and armed with a 'cold-blooded' unforgiving hyper-detailed presentation, the K7xx can battle against the 'giants' of the headphone world without being embarrassed.
 

Picture of my testing set-up
 
Massdrop Product link: https://www.massdrop.com/buy/akg-k7xx-massdrop-first-edition-headphones?s=akg%20k7xx
***please note, the First Edition drop has currently ended, non-serialized models may possibly be available in the future if enough requests.***
***Update on 5/25/15: A second production run of Limited Edition K7xx is currently available on Massdrop and will ship 6/26/15***

im bad at reviews

Between my VModa Crossfade LP's, the Grado SR-80i's, AKG K240's, and the TTPOD TT-1E, the AKG 7XX headphones easily sound the best. They have a great fitment, and can be worn for hours, plus they also have a very clear sound. I'm definitely hearing details in songs that I have only ever heard with the Grado's, but with much more bass extension than my Grado's ever offered. I would definitely recommend this headphones to anyone I know willing to put down 200 for some great headphones.

Intro
 
Well, after almost two years on Head-fi, I feel it is time to put my words out there and write my first review. In doing so, I feel it is only right that it be about the newly released AKG K7XX Massdrop First Edition. There are only a few days left on the final drop of 1000 units, and with no definite word on whether production will continue, I feel the need to make people aware of just how wonderful these babies are, and for only $200! This has been the best value per performance ratio that I have heard out of any headphone to date in my short audiophile-ish life. I chose to purchase this headphone because I am an avid lover of the AKG house sound; some of my most favorite headphones, to date, are the K712 and K702 65^th Anniversary Edition.
 
Now, I have to re-iterate on my short audiophile-ish life (key in on ish) before continuing. This is my first review and I want readers to familiarize themselves with my preferences and experience. I have yet to expand my listening on the higher end stuff. My limited experience consists of mostly mid-fi headphones under $500 on similarly priced sources and gear. If you want to see my current and prior line-up, just check out my profile. I prefer warm, bassy headphones, with slightly recessed mids and smooth but not recessed treble (SRH1540, anyone?). I do, however, appreciate other sound signatures for their strengths, but am not the flat response neutral-head audiophile. I mostly listen to Rap/Hip Hop and R&B/Soul, with some Jazz, Reggae, Classic Rock, and Pop on occasions.
 
Okay, enough about me. On to the star of the show…
 
AKG K7XX Massdrop First Edition Review
 
Physical build and accessories:
 
The K7XX is built pretty nicely and is sturdy for such a light headphone. It has an adjustable flat leather headband, (ridding the bumps of prior models such as the K701, K702, and Q701) and the ear pads are made of soft memory foam.
 
It doesn't come with many accessories, which I believe to be its biggest con. All you receive is the headphones, a 10ft mini XLR to 1/8 inch cable, a 1/4 inch adapter, and manufacturer paperwork. Still, for the asking price, there is not much to complain about, here. The K702 65^th Anniversary Edition is almost twice its price and comes with the same accessories. Only the K712 has a decent amount of accessories included (two cables and a carrying bag), and even that is almost twice the price of the K7XX.
 
Comfort:
 
When I say comfortable, man, these are COMFORTABLE!!! I mostly use these for gaming on my PS4, which often end up being sessions of hours upon hours on end (no, I don't have much of a life outside of school and work *sad face*). This is the only headphone I have been able to wear for so long without any fatigue from comfort or sound. If you need a headphone for long listening sessions, and the sound fits your preference, look no where else. You have found your perfect match (I did!).
 
Sound:
 
Massdrop claims that their signature AKG K7XX has a matched response to that of the AKG K702 65^th Anniversary Edition by using the same driver technology. Well, based off memory, I can confirm that this is correct. I owned the Anniversary a while back and, as I mentioned before, this is familiar territory for me as I am extremely fond of that headphone.
 
The bass is tight, articulate, and just north of neutral to my ears. It does a great job of being present while not bleeding into the mids. It kicks when it needs to, and relaxes when asked. It does a beautiful job of mixing in with the rest of the spectrum, while still being slightly warm and liking for the consumer audience. The extension is very nice, but not as deep as the likes of its open counterpart, the K612. Still, AKG does a great job of improving the bass presence of the drier K702/Q701 with this wonderful headphone. Bassheads, however, may need to look elsewhere. Though it is one of the K7XX's strengths, it is by far NOT a bassy headphone.
 
The mids are also a strong point, here. Though not as forward as the likes of most mid-centric cans, I just love how its voice presentation blends in. Vocals absolutely shine when it is the star of the show, and the fact that there is no bass bleed makes for a wonderfully smooth experience. Male vocals are more present than female, but there is a slight grain in the upper mid range on certain tracks. This is a similar experience that I had with the K702 Anniversary Edition, which was the major difference between it and the K712 I purchased right after, which slightly improves on that minor flaw. The K7XX has that same flaw, so I can assume that difference is the same when compared to the smoother K712.
 
Highs are the most sensitive frequency range for my ears. I do not like overly bright headphones, though I do appreciate their detail and clarity on certain genres. The K7XX's treble does a great job of falling right where I want it to be, detailed without being bright or recessed. If I were to make an analogy, I would have to say the highs are that one person in the crowd who is unique and appealing, but doesn't necessarily stand out. The treble is very well behaved while still having a good level of clarity and presence. It is by far some of the best treble I have heard on an open headphone. It can be a bit brittle, at times, but I think that is more to blame on the poorly recorded track rather than the headphones.
 
My favorite thing about this headphone is its wonderful soundstage and instrument seperation. Because of the large soundstage, it allows the K7XX to have no weaknesses in its sound presentation. The slightly north of neutral bass has room to breathe, resulting in that sensual transition from lows to mids without any muddiness or bass bleed. Also, when gaming, the large soundtstage allows for pin point accuracy when trying to define where sounds are coming from. A definite strength, arguably its best.
 
Sound leakage and isolation is poor, but that is to be expected from an open headphone. This is strictly for home use in quiet environments.
 
Amplification:
 
Though not required, it is ideal that one provides the right synergy for this fantastic headphone. It absolutely loves juice, so don't cheat it from its vitamin C. The K7XX scales extremely well with proper amplification.
 
Conclusion:
 
Massdrop's variation of AKG's K700 line is one that is surprisingly low priced based on its sound performance. The AKG K7XX Massdrop First Edition is a great all-rounder, one that does most, if not all, genres very well. I know this can be a bit cliché, but it is indeed a jack of all trades kind of headphone. If you are looking for a good headphone for all purposes at home, this is one you should look at very closely. There is no definite timetable for when/if AKG will manufacture more, so I strongly suggest to get your hands on one if the situation calls for it.
 
It has been my pleasure to share my thoughts with you all about this marvelous headphone. I hope I touched on most of what readers search for when reading a headphone review. Please feel free to give me some feedback and pointers for future reviews, should I have missed or messed up on anything. Thank you for reading!
 

To start this review off, I've owned several AKGs, including the Q701 Quincy Jones, the K702 65th Anniversary, K240 MK II, and until a few months ago, the K612 Pro. I was craving another AKG, and before I pulled the trigger on the pumpkin-colored USD 350-400 K712 Pro, the internet bulk buying site Massdrop announced that they were partnering with AKG to make the special edition K7XX Massdrop Edition. Made in China instead of Austria, I was originally skeptical that AKG was able to hold up their claim that they made a 200 dollar version of their 500 dollar K702 65th Anniversary Edition. I thought it was a needless purchase, since I previously owned an 'Annie and there wouldn't be anything new to refresh my enthusiasm. However after inquiring from another AKG enthusiast, the K7XX would sound different from my former K702 Annie and it was worth a shot.
 
This is where things get a little complicated:
 
My K702 Annie was an early production (EP) model, which predated its mass production younger sibling, the K712 Pro. The EP K702 Annies and K712 Pro do not sound the same due to different tuning and slightly different memory foam padding between the models. The EP K702 Annies have a dark mid and upper treble, a boosted upper mid section, a slightly boosted bass overall from the K702 and Q701, and a fairly closed in soundstage. The K712s have more mid to upper treble, a little extra mid bass emphasis over the Annies, and a more open, wider soundstage. Whereas the EP K702 Annies have an intimate, treble-dark, thick, mid forward sound, the K712 Pros have a somewhat U-shaped sound. HOWEVER, AKG in the later production run of the K702 Annies retuned them to sound more like the K712s, giving them a little more mid treble, warmer bass, less exaggerated upper mids, and a wider soundstage to become a sonic hybrid of the K712 Pro and the EP K702 Annies. This retuned version of the K702 Annie was what AKG based the K7XX on. This wasn't the first time AKG tuned older versions of a headphone to sound more similar to a newer version. When AKG launched the first K7 incarnation, the K701 back in 2006, and later the dark blue K702, they received a number of complaints that the headphones had little to no physicality to the bass, plastic sounding and overly zazzy treble, and no warmth to the mids. When the Q701 Quincy Jones Edition was introduced, AKG soon redesigned and relaunched the K701 and K702, which now sounded like the Q701, having better behaved treble, less diffused soundstage and slightly warmer upper bass. When reviewers state that the K701, K702 and Q701 sound the same, this is because they are listening to the retuned models, and not the colder, brighter earlier versions. 
 
Here are some pictures. Each image belongs to its respective owner. 
 
K701
 
K702
 
Q701
 
K702 Annie
 
K712 Pro
 
Now that I've clarified this potential confusion, onto the review. 
 
The K7XX build-wise is pretty much identical to its K7 siblings, with its large driver capsules, matte finished plastic from the K702 Annie and K712, a single sided detachable cable terminated to a 3 pin mini XLR connector (sorry balanced audio fans, this isn't going to be as easy to run balanced as a Sennheiser HD600/650), and a genuine leather, bump-free headband just like the Annies, K712, and now Chinese made black K702. The K7XX is an all matte black headphone with black ear cups, black cable, and black headband rails. It has a very handsome and stealthy appearance. So if some of you didn't like the black and orange K712 and thought it looked like the headphone incarnation of a KTM motorcycle (also Austrian), or if you crave the headphone equivalent of a black helicopter, the K7XX may be just for you. What's interesting is that the first model of K7s, the K701, was an all-white headphone, while the latest model, the K7XX, is all-black. Maybe this is a sign that the color gamut has ended and this will be the last version of the K7 family? Who knows. The K7XX like the K7s now made in China, doesn't quite have as nice a build as the Austrian and Slovak-made K7s, so there is a bit you give up in build for a cheaper headphone. But not a ton. 
 
So as comfort goes, the K7XX is about as comfortable as a K7 can possibly get. The clamp is enough to keep them on my head without making them a vice grip, the headband is auto adjusting via elastic straps and as I mentioned has zero bumps underneath it to give my skull hot spots. The ear pads are fairly large in size and while the openings are circular and not the largest in diameter to allow long ears to float freely in them, they are plenty deep, never overheat, and have a very luxuious velour wrapping. They are deeper than the K702 Annie pads, which I found weren't deep enough for my ears, causing them to touch the driver covers. Not the case here. The foam padding while firm and super dense, conforms seamlessly to the the head and requires no break in to achieve a seal around the ears. This is some of the best use of memory foam padding I have experienced in a headphone. I expect this padding to keep its compliance and strength for quite some time. While it might seem somewhat firm at first, it disappears over your head.
 
Now onto sound.
 
The K7XX to my ears has a level of refinement, resolution and dynamics that most other 200 dollar open backs simply cannot deliver. For an AKG, it's a slightly warmer and wetter sound, but compared to Sennheisers it still remains a little dry.
 
Soundstage has a good amount of imaging and instrument placement, while not having the tendency to pan left and right, with the center stage going dead like on the K701 and K702. There isn't this level of airiness or diffusion one might expect from an open back, but soundstage by no means is cupped or closed in. 
 
The treble to my ears has great air and extension when the situation calls for it, but otherwise remains neutral and kept in check. When amplified adequately and fed good quality audio, it never goes out of control with splashy or sibilant highs. There is some brightness in the mid treble that becomes apparent on aggressive sounding equipment, but not artificially so. I wouldn't call the K7 dark nor bright, but neutral and right where it needs to be. It has enough treble to be good with shredding guitar solos and high hats on rock, while having enough air for violins and stringed instruments. 
 
The mids on the K7XX have that sightly dry and analytical texture to them, with great speed, detail and presence without sounding brash or shouty in the upper mids like the Q701 often did, especially with women vocalists, saxophones and trumpets. When underamped, the K7XX can sound withdrawn or hollow in the mids. I have no complaints about the mids and vocals. They are exactly where I want them, and they deliver that AKG house sound, while not needing to overboost the lower treble. 
 
The bass on the K7XX is another one of its strong suits. The bass is some of the best resolving and extending, and tightest I have heard of any mid-fi dynamic headphone, and rivals if not beats most equivalent open backs. But this shouldn't be a surprise, as bass tightness and speed is a strong suit on contemporary AKGs when they are amplified right. Where the K7XX doesn't have the most emphasis in is the upper bass to the mid bass, where accentuations in these frequencies give the mids that bloomy, chesty, filled in sound (think Sennheiser HD650 or Shure SRH1540). The upper bass and mid bass, however, still hit and punch when they need to. Kick drums and stringed bass still have plenty of energy. The K7XX can make a great house music and trance headphone. The sub bass is a high point, with excellent low end energy and tightness. The K7XX doesn't have that annoying open back dynamic headphone tendency to dive off a cliff in the sub bass. The K7XX has a surprising amount of rumble to it. Due to its great low end extension, and tight, fast upper to mid bass without a bloat or bloom to slow it down, the K7XX makes a great Drum and Bass headphone. 
 
 
Next up: amplification. 
 
The K7XX like all other K7s is 62 ohms, with an impedance curve that stays astonishingly flat and steady throughout the entire audible sound spectrum, only increasingly slightly in the very upper treble. This is very unusual for a dynamic headphone, and it's something one only sees with planar magnetic headphones like the Hifiman HE400i, HE560, and the Audeze LCD series. This low impedance tends to mislead people to think that it's an easy to drive, efficient dynamic headphone, which it isn't. Many reviews I hear from people saying the K7 series has sibilant treble, hollow mids, and dull bass most often is a result of underamplifying the headphone, or running it on an amplifier that it doesn't like. The K7XX may be a steady 62 ohms of impedance, but it isn't very sensitive and is current hungry. It sounds best on a desktop mains-powered amplifier with a good quality sound card. There are claims that the K7s sound best on an all-solid state amplifier due to its steady power output and its more current output at lower ohms than all tube headphone amplifiers, but if the amp is good enough, the K7XX will sound great regardless of whether it is a tube or solid state amplifier. 
 
My personal rig that I use the K7XX with is the Schiit Audio modi USB DAC, and the Lyr 2 hybrid tube and solid state headphone amplifier, which can output up to 6 watts of power at 32 ohms, with max power decreasing to 330 milliwatts at 600 ohms. It's a great amplifier with the K7XX, delivering tons of power when I need it, though in high gain mode with the stock 6BZ7 Canadian-made tubes becomes a little aggressive in the treble and upper mids. Other good headphone amplifier options include the solid state Burson Audio Conductor and Violectric HPA-V200, and the all-tube OTC Woo Audio WA6 (which according to fellow Head-Fi user Hifiguy528 does a great job driving K7-series models), WA6-SE and WA7 Fireflies. I do not recommend OTL amplifiers like the Schiit Audio Valhalla, Darkvoice 336SE, Bottlehead Crack, and Woo Audio WA3, as their high output impedance and lack of current at lower ohms will not play well with the K7XX. If you go the tube route, then make sure you either get an output transformer coupled (OTC) or hybrid model. Basically the more refined and powerful the amplifier, the more the K7XX will like it. On the cheaper end, the solid state JDS Labs Objective 2 and tube hybrid Schiit Audio Vali will both do an admirable job, with the Vali bringing a little more energy and excitement to the sound than the O2. The K7XX scales up noticeably with equipment, so it can remain a staple in one's headphone fleet, even with upgrades in equipment. 
 
 
Oh, and as for burn in, the K7XX like most other K7's needs 200-300 hours of burn in before it sounds best. If you put it on right out of the box and start listening without any burn in you will be sorely disappointed. Before the 150 hour burn-in mark, the K7XX treble is sibilant, the mids are highly recessed, and the bass lacks weight. Put a good 100-150 hours of burn in on the K7XX before doing any sort of serious listening. After 250-300 hours or so the K7XX will really start to sound as it was intended to.
 
If you made it to the end of this odyssey-like review, I thank you for your time and patience. If desired, I will do a follow review comparing the K7XX to my Sennheiser HD650. Cheers. 

PreIntroduction:

 

I am in no way affiliated or work for AKG or Massdrop, and for this review, I did not receive this item as a review sample. I’m a 19 year old college student who likes his music pure, and would hope that in the future, teens could appreciate the audiophile community the same way I do. Enjoy!

 

Keep in mind that all the pictures, while looking small on the page, were taken by a mid-resolution camera. I just didn't want to clutter up the page with large pictures. So feel free to click on them to see them in full resolution throughout the review!

 

Introduction:

 

There have been (at least for a while) the “kings” of price per performance in the headphone market. Starting with the lowly mod-able Monoprice 8323, jumping up to the Audio Technica ATH-M50’s, and then the Sennheiser 600/650 to name but a few. People are always on the search for a new budget king, and that’s sort of why the Massdrop/AKG K7XX made such a stir. This may be fitting to go in the “king” category.

 

You see, AKG had quite a few headphones in the K7 family, including the K701, Q701, K702, K712, and K702 Anniversary edition. I can imagine someone new to this thinking-

 

“What does all of this mean? …I’m bad enough at spelling as it is, now I have to remember 5 similar-but-different names of headphones and their differences?!?”

 

Well, fear not. All you gotta know is that the last two I mentioned (which you don’t even have to remember their names) are/were about $450 in stores, maybe $400 if you get a deal. The K7XX (the headphone I’m reviewing) sells for $200 list price, and will probably stay that way.

 

Now, if price was an indicator, which it usually is, you would probably think that the K7XX is worse off than the $450 ones, right?

 

Wrong. Well, mostly, anyway.

 

From what I understand, the K7XX was a collaboration between AKG and Massdrop, an online community where people can participate in group buys, which usually means lower price. The new K7XX edition is an improvement on the $450 pair. Why is it so cheap? Because Massdrop got a quote for 2000 people willing to participate in the group buy, all within a span of 6 days.

 

If Massdrop could assure that 2000 people buy this product in a week, then AKG would be more than happy to lower the price to $200. The buyers win, because they get a quite superior headphone for a greatly reduced price. AKG wins, because they can sell thousands of headphone straight from the get-go. Massdrop wins, because whether or not they get a share of the earnings (which I have no idea if they do), Massdrop as a website gets a lot of publicity, and chances are if you buy something once from them, you’ll buy again.

 

What happened? Massdrop sold 2782 (if my memory serves correctly) pairs of the K7XX in a week. They reinstated the drop again another 2 times that I’ve seen, both selling in the hundreds. So everybody’s (or almost, anyway) been happy.

 

I’ll go through some of the major points, as well as some things you should be aware of. Enjoy!

 

Packaging:

 

Standard, looks nice. I’m not much of a believer in packaging to begin with, so here’s 2 pictures. Otherwise, we’re done.
 

 
Build Quality:

 



Overall, it’s quite good. The cups feel solid. However, from what I picked up here and there, the more expensive models it’s based on (the K702 Anniversary edition, and the K712) are better built. There’s been some talk of the earlier ones being built in Austria while these were built in China, but honestly, for all the hype that China-built stuff aren’t good, these are built quite well.
 

The K7XX is built quite interestingly, though. Instead of an extension in the headband that you could make longer/shorter based on your head height, these stretch to your head through some elastic string on each side (scroll a bit down to picture 1). While I’m comfortable with the elastics themselves (they seem sturdy enough), although I was afraid the tension will wear out after a year or two, the plastic piece connected to them had my full concern (picture 2). I thought they would snap, break, or a combination of the two well within two years. From the time I've had it though, everything works well, and my initial concerns were for naught. It is strong plastic though, so perhaps it's built to last.

 

However, from those who’ve had the earlier models (which operate the same way), it seems that my concern is only an initial reaction. They’ve said that the elastic/plastic pieces work well, and as a reminder, they’re backed by a two year warranty. So if you feel alarmed like me, relax a little. They’re most probably going to last.

 

Along the top are 2 separate things, interesting as well. There’s the leather headband (picture 4, second row), which is quite comfortable, and is what you rest your head on. The previous models had uncomfortable bumps on them, so the K7XX being “bump-free” is a relief to many familiar with the AKG family. On top of the headband, though, there’s two long plastic pieces running almost directly parallel to the leather headband. This is really hard to explain, so please look at picture 5 (second row) to see what I’m talking about.

 

Those two long plastic pieces thingamajigs are, to my understanding, what keeps the cups connected. So I was also initially concerned with those, as the plastic…doesn’t feel too sturdy at all. However, I am brand new to the AKG headphones, and if they did it well until now with previous models, who am I to judge? Just to be aware though, don’t treat this like a Lenovo Yoga Flex 2.

 





 

Cups and Pads/Cushions:

 

The cups are really nice, all black… they look SO much better than the Q701’s, which many are green, or the K702’s, which are white and black, or… 

 

…This is a full-sized open back headphone, and you’re not going outside with these. This review is not for aesthetics, and it’s not going to be a decoration on the wall but on our ears. So, yes, it looks nice. All black, a step up color-wise from the other models in my opinion. But that’s it. I’m not spending 2 pages on comparing the color themes, for crying out loud. 

 
Cushions are very comfortable, reminds me of those memory foam pads. Big enough to cover most sized ears without a problem. In fact, these are huge to people who haven’t seen many full-sized headphones before. But that’s just the way these types of headphones are made.

 

There’s also a comfy inner cushion as well, directly covering the driver opening. So for those who feel that their ears are going to touch the inside of the cups, there’s padding for that as well. How considerate.

 

Both indicate they can be worn for hours without too much of a problem, although since the cups are so big you may have to readjust them on your head once in a while.

 

Ehm, I had a problem when I first got them, which was since these are so much bigger than my ear, in which position do the cups go over your ears… do you want the front of your ear touching the front part of the pad or the back of your ear touching the back part of the cushion? Although this sounds ridiculous, there is a different sound depending on which way you do it. I settled on pushing the cups forward, i.e. keeping my ear mostly towards the back part of the cup.

 

Awkward time over. Next section. 

 

Sound:

 

Here we go. This I’m familiar with.

 

First off, these headphones are quite lively. You can hear from the sound that they were meant for listening/relaxing, rather than mixing and studio purposes. Sounding very natural, which is a feat not all headphones can brag about, the K7XX in my honest opinion leave the “everything has to be exact and dry” category to enter the “be happy with me” one. While staying fairly accurate and natural, this pair knows how to twist the EQ here and there to make it sound impressive.

 

Lows/Bass: I’ve heard that people complained about the previous AKG models being “bass-lacking”, so AKG added a bit of a boost to this one. Nice and welcome, and doesn’t friggin’ take control of the frequency like those who say “oh, it’s not overpowering” and then they show you V-Moda’s. These are a part of the frequency, nothing more. You won’t feel like these have too much at all, while still staying prominent. They just have a slight boost. I am an anti-basshead as well, if there’s such a thing, so hopefully I can gain your trust with that.

 

While great in quantity, clarity, and size, to me they could have been a tad more controlled on the lower end. I did come from a closed back studio headphone, but even compared to many openback’s I have tried (Beyer T90, specifically) the bass seems a little “out there,” rather than controlled where you know when it begins and ends. The effect is one where it takes you into the music, rather than leaves you to dissect the sound. I think AKG may have done that purposefully, so that it can immerse you better, but more on that later.

 

Mids: Acoustics (guitar, cello, etc.) sound great and natural, although that should be a given based off the natural quality of these headphones. Vocals can be a bit tricky though. Either it’s my choice of amp (more on that later) or the headphones themselves, but unless the recording is mastered well (and not 3/4 of the pop songs out there), I’m personally left a little bit unsatisfied with the vocals. Even with well-recorded music and a good amp, the vocals don’t jump out at you. Or maybe my vocals aren’t that well recorded after all. Either way, if vocals are a big part of your music, brace yourself. It will show you the bad in those, if there are any. Any type of instrument sounds great with these though. Basically anything but vocals get a +1 from me.

 

Highs: Done quite well; I have no complaints about these. They still have that “snap” I’m so fond of, and quite a relief too. Drums sound better than I can ask for, although when mixing in with the type of bass the K7XX provides it perplexes me a bit.

 

Coloration: not much to say here, besides for that there’s really not much coloration going on here. Quantity differences, yes. Coloration, no.

 

Soundstage: Wide, oh wide. I mean height and depth too, not just wide. Big sound from a big headphone, although this is really famous with most of the AKG lineup. Definitely helps in terms of “getting into” the music. Very 3D-sounding, especially given the imaging. Natural + Soundstage = WIN in this case. Helps with the immersion factor tremendously (later section).

 

Imaging: Done well, although higher-end flagships may do it better. Nothing to complain about here.

 

Frequency Shape:  If I had to say, it would be slightly V-shaped, due to (what I think, anyway) a slightly boosted bass and treble. Not ATH-M50 V-shaped, only slightly.

 

Detail & Extension: Detail retrieval is as good as it needs to be, in my opinion. The bass is quite extended. However, the mids could use a bit more of detail, in my opinion. Studio headphones in particular are going to shine more in the detail department, but that doesn’t mean these are bad in any way.

 

Coherency and Flow: Very, very well done. AKG took a loud and big type of sound for the bass, a slightly smaller one for the mids, and a very precise sound for the highs, and made it all flow together. If all three parts of the frequency was like the lows, it would sound quite muddy. Everything like the mids, it would sound lacking. All like the Highs and there would be no way to immerse yourself in the music; it would be too techinical. AKG took all three and fused it into an interesting but enjoyable sound.

 

Immersion Factor: Crowning glory of this headphone, in my opinion. Technical details are really only there to help you hear what’s in your music, but we often forget about how enjoyable and immerse-able your headphones let your music become. The K7XX zones you in as if you’re at the center of the entire piece, which can only be done through all of the above.

 

Genres: EDM/Rave music, do not sound great with these, in my opinion. EDM thrives off of sharp and concise bass, and a natural sounding headphone won’t do much good for EDM either. Imagine a “natural” EDM instrument, if there was one. Blegh. Regular electronic sounds great though, but don’t expect this to be a dubstep headphone. Classical isn’t the shining glory with my amp right now, due to the amount of bass present in the setup. It still stays quite enjoyable though, even when not at it’s true best. Anything natural sounding (i.e. most instrumental music) and anything that thrives off a huge soundstage (psychedelic music, for example [Shpongle]) will sound really great.

 

I hate “fun” headphones. Like, really hate them. But sometimes studio headphones make your listening very dry and unlively. What AKG did well here is provide life to the music. I spent quite a few months before the K7XX with only a Studio headphone, and I have to say that the K7XX makes me much happier. Is it flat? No. Does it have a bit of extra bass? Yup. Is the frequency strung flat to the HD800’s? No. But if you’re ready to leave because it’s not as accurate as studio’s (and I don’t mean Beats), remember the LCD Flagship lineup. Are those LCD’s priced $1000-$2000 flat either? Not really. Also have a little boost in the lows, and some other frequency tweaks to my ear that make it sound more enjoyable.

 

For these reasons, I would say that the K7XX is an extremely immersive and enjoyable headphone. People who are looking for a high quality recording headphone should steer clear of this; it’s very likely to space out into the music instead of focusing on the recording itself. To say it in another way, these are more geared to a listener's perspective than a recorder's perspective. Their crowning ability in my opinion is how fast you can really "get lost" or space out with these headphones (they're great to relax). For a recorder, that may turn out to be harmful; you don't really want to space out when singing, you want to focus on what you have to do.

 

I would consider other high-reference/studio headphones as a 4k resolution screen, while the K7XX is IMAX at 1080p. Not everything is about the resolution; the type of screen makes a difference too.

 

And in this respect, AKG couldn’t have done better.

 

Amplification:

 

I really, really didn’t want to come to this section, because it’s so darn tricky. But here’s what I learned so far:

 

The K7XX are rated a 62 ohm headphone. 62 ohms aren’t usually enough to warrant a powerful amplifier, and most definitely doesn’t need one by any means. HOWEVER, akg’s K7 family are the quite opposite of that; they usually need quite a bit of power (and a good sounding amp, obviously) to sound good, more than the 300 ohm HD600’s from my understanding. I’ve tried the K7XX with a few low-mid tier amplifiers, and it friggin’ changes every time. Imagine how hard it is for me to do a review sound-wise when the EQ changes with every amp I own/have owned.

 

So if you think you can get away with this headphone without an amp, don’t. It absolutely needs one, I cannot stress this more. I’ve heard reviews saying that almost any good amp will do, and, to my understanding, that’s not entirely correct. Let me show you what I mean:

 

Nuforce Udac-2 dac/amp: Sounded pretty good for the first pairing, albeit not so “full” sounding. Vocals sounded awful, it was like the K7XX was a recording quality nazi.

 

Fiio E18: Colored, and awful sounding. On top of that, I always needed to push the volume up a little more, or else it sounded teeny. You know if you have to push the volume up that the headphone is not getting enough juice…

 

Schiit Magni 2 Uber: More than plenty of power, maybe almost a bit too much. Overall sound in the mids is too abrasive to my ears, and when the bass hits, it hurts my ears. Low gain was better, but still didn’t sound too great. Overall detail, clarity, etc. of the highs, mids, lows were slightly better than with the (next) Fiio E12.

 

Fiio E12: Finally, a good sounding pairing. The E12 is on the lower side of amps, though, so keep in mind that it will sound a bit more “warm” or “wet” than higher-end amps. Not colored in any way though, so that’s a plus.

 

Aune B1: For a standalone amplifier, the B1 sounds absolutely fantastic with the K7XX - smooth, very musical, and a real pleasure to listen to. Better than with the Fiio E12,, in my opinion, but both sound great, so don't "feel bad" if you don't have the money to buy the B1.

 

Heir Audio Rendition 1 Amplifier: A big name for a decent amplifier; while a mid-tier amp, and really great with all lower impedance headphones I’ve tried (Bang & Olufsen H6, KRK KNS8400), I’m basically getting a smaller version of the problem that the Fiio E18 had. I’m not feeling that the Rendition 1 is giving a full sound, although it’s possible that’s coming from the fact a just left a quite warm amplifier for a colder one. I hear all the details and clarity a mid-tier amp should, still, it leaves the K7XX underpowered. It becomes a little fatiguing as well.

 

CEntrance DACport Slim: This is the pairing that you should get if you're on a budget. The Slim is a DAC/amp all in one, and is quite small too. It was actually made with the K7XX in mind, so it's no wonder they work really great together. This pairing will get a good 90% (just to throw out a number) of what you'll hear from this headphone, and it's a beautifully sounding pair. I highly recommend this  pairing - especially since as DAC/amp's go, $100 is really not asking for much, much less for a powerful, good sounding piece of equipment.

 

Grace/Massdrop m9XX: I don't think anyone who has some vague form of a budget will actually be buying the m9XX, but I'd like to say that the K7XX scales very, very well with higher-end equipment such as the m9XX. In fact, with this DAC/amp (m9XX), it sounds like something double its actual cost - knocking out the HD600 and HD650, in my opinion.

 

…So, what you can hopefully take from this is that the K7XX, to me, can get quite picky. It may be why my vocal collection is getting different impressions from me as I move along. The CEntrance DACport Slim is the best budget-oriented choice to pair the K7XX with, but the Magni 2 is definitely not. Keep in mind you must have an amp to make the ‘phones sound their potential, and that these will scale wonderfully with higher tier amps. Basically, when moving up, you’ll really only need to replace the amp and/or source player, not the K7XX; the mark of a truly good headphone.

 

Price & Value:

 

As other reviews have said, for $200 there’s nothing like it. The soundstage, 3d presentation, and immersion factor coupled with quite impressive sound totally destroys most headphones in its price range. Ath-M50X? Not even close. I don’t know any closed-back headphones across the price spectrum that has presentation like this one. One head-fi’er told me during a meet that after this, it starts getting into the law of diminishing returns, so here’s a great place to start – and end, if you’re on a budget.

 

Now, the Sennheiser HD600’s can be had for ~$275 slightly used throughout the year, and $260 on black Friday. To me, they are both budget kings though. The HD600’s excel at a more balanced sound, and are great for recording purposes. The new K7XX is fabulous at listening to music to enjoy it, and immerses you like a boss. So I can’t say that one is better than the other, rather they are two very different types of headphones to be used for different purposes.

 

Conclusion:

 

Giant killers? Maybe. Either way, you won’t find out unless you find at least a good amp that pumps out a decent amount of power. For beginners, this is the one headphone you’ll be satisfied with in this price range, just watch out for the cost that amplifiers can cost you, and stick to the ones known well to work with it. The E12 is a great beginner option, but you will have to shell out ~$100 for that – not really great for people on a budget. The DACport Slim is the same price, but is a DAC as well, so it justifies the cost just a bit. Keep in mind though that it’s a completely different beast than probably any closed back headphone you’ve worn until now. Feed it right, and it can be a monster.

 

For the people familiar with headphones, I can’t bring frequency charts like other reviews do, but to my ear it can be a giant killer, with the right equipment. It won’t be to the same level that the HD800’s are, or the HE1000. But sub-$1000 it provides plenty of competition, and wins most of them, to me. Keep in mind the ear I’m using is the same one that was used in a blindfolded test of mid-high tier headphones for a bet with a friend, as well as during the HE1000 impressions, so you might want to trust me a bit beyond my age. Either way, though, expect to feed this well, and for the amplifier to be lagging behind the headphones for a while. Keep in mind the reminders on the build quality, although most say they shouldn’t be a problem. This isn’t a “basshead” headphone, although it is a bit bass-prominent, which may leave you with mixed feeling for your classical collection. Try to couple it with a bass-light amp, if you have one. Either way, it provides a really interesting sound that’s hard to miss; enjoyable, huge, and very immersive.

 

Quick Summary/Short Version:

 

1. These headphones are HUGE. To new users of open-backs.

 

2. That said, it provides amazing soundstage/imaging, and are very comfortable. Headband has no bumps, and earpads are of memory foam.

 

3. Very decent amount of detail. The extension is okay, while still decent; I don't feel it to be lacking.

 

4. Very natural sounding, so for anything that was quickly digitalized and/or vocals that weren't recorded perfectly, you WILL hear it with some amps. The upside and downside of any real decent headphone.

 

5. YOU NEED a great amp for these to sound their full potential. Since I upgraded to the Fiio E12, the pairing was good, although limited by the E12… These headphones scale with the amp you use.

 

6. Highs are great, still natural sounding, so maybe it doesn't have that snap drums have with studio headphones; it's more of a satisfying "thump". Precision is accurate, detail is great, and for an very open headphone, you can't ask for anything more.

 

7. Mids/Vocals sound freakishly natural, so any pop artists that use only "okay" recording equipment won't sound amazing with certain amps. These headphones will only sound as good as the recording, as any should. Not very forgiving.

 

8. The bass boost is very welcome and heard, but not overpowering. Could be a bit more controlled in my opinion, but maybe I'll change my mind after a few days with these. Edit: after a while, I feel that the bass, while not as controlled as some studio headphones, are there to suck you into the music, and suck you in it does.

 

9. It's interesting to have a bass boost in a natural and neutral headphone like these, but it surprisingly all fits together.

 

10. No rattling in mine, and everything sounds great.

 

11. I have not seen a more decent $200 headphone, and that is saying a lot. This to me is -by far- the best headphone in its price range - the HD600's was for years, but now this a cheaper, different, and more unique option. For every the criticism's in this review, there's another 3 positives with this new, affordable, and incredible sounding headphones.

 

12. These headphone make the music blend in together, while the instruments stay separate. Studio headphones - these are not, but reference they are and make a very good casual listening headphone too. Again, I don't like coloration, but even though these aren't studio 'phones, they are very natural in their presentation.

 

13. EDM/Dubstep will almost never sound great on a open natural-sounding headphone, and these are no exception. You probably want this if you have a lot of instrumental music, vocals that you can swear by that they had good recording equipment, and even electronic music that has no dubstep/scratching.

 

14. The Piano Guys, Lindsey Stirling, and most of OCRemix's albums (especially Deus Ex Augmentation) really shine with these.

 

15. Thank you to 1bentley4ever for catching the upper treble spike. It gives the impression of a more sharp headphone, while retaining bass. I wouldn't say these are U-shaped, but they seem to have a very slight V-shape sound.  

 

16. These headphones are great! I don't feel a need to upgrade anymore, although I wish picking an amp for this beast would be an easier matter...

 

Hope you enjoyed! Suggestions/criticisms are welcome.

EDIT: Head-fi didn't really let me scratch my old first impressions and post this new review, so I had to "edit" my previous impressions and use the same post date.... Post date for the review is 5/17/2015. Thank you!

 

Other picture(s):