Pros: very competitive pricing, extremely large soundstage, natural-sounding sound signature, great overall SQ and resolution, extremely revealing
Cons: not widely available, earcups a bit shallow, unforgiving on poor source files
AKG K7xx Massdrop 1st Edition Headphone Review:
Intro:***Disclaimer*** (Click to show)
Manufacturing headphones since 1949 and responsible for many innovations such as the world’s first supra-aural open-back headphones (the K50 in 1959), AKG Acoustics is an Austrian company producing high quality audio gear including microphones and headphones.
Released in 2005 with an official MSRP of $539, the original AKG K701 quickly replaced for their previous flagship, the K1000 (now discontinued). Prior to age of $1,000+ headphones heralded by the release of the Sennheiser HD800 in 2009, the AKG K701 ruled the headphone scene as a “flagship” pair of headphones, one of the best non-exotic dynamic headphones that money could buy. The ‘old school trio’ of flagship dynamic headphones consisted of the best offerings from AKG, Beyerdynamic, and Sennheiser.
AKG has followed up the K701’s success with revised versions that include the K702, Q701, K702 65th Anniversary edition (MSRP $650), and K712 pro. AKG’s K7-series headphones have always included their most premium reference headphones, offering the best of AKG technology until the recent release of their current flagship, the K812 pro in 2013.
Despite being downgraded to a ‘mid-level/mid-fi’ pair of headphones with the new crop of $1,000+ flagships, the AKG K7-series still has an extremely loyal following among headphone enthusiasts, providing very high-end performance at attainable price points.
Interesting video link on how the AKG K702 are made here.
Massdrop is community-driven commerce website founded in 2012 that organizes bulk orders for popular products based on discussion and polling to achieve nice group discounts. The Massdrop community currently has over 1 million active users every month. Official Massdrop website here.
How Massdrop Works: Community members can create and vote through polls on desired products. For popular polls, the Massdrop team will contact vendors to procure the item in bulk at discount prices. The item is then "dropped" on the website for a limited time allowing members to join the 'drop.' If enough people join the drop within the time frame, the drop will be successful and the bulk order will be placed. There are often lower pricing tiers that get unlocked as more people join a drop. Use 'Join Now' to reserve a spot in the drop regardless of whether the lowest pricing tier is unlocked. Use 'Commit to join' to only reserve a spot for the lowest pricing tier. After the drop ends, the product page will still be available for 'requests'. If enough requests are reached, the Massdrop will try to organize another drop. Typically, a minimum of 200 requests are required before a new drop on a previously dropped item. Please note shipping times will be longer than traditional retailers as the item gets shipped from the vendor to Massdrop then to the consumer.
more information here: https://www.massdrop.com/faq
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.
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.
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)***Some examples of notable test tracks strongly demonstrate the following:*** (Click to show)
This list arranged by alphabetically by artist. Obviously, many of these songs are useful for testing multiple sonic strengths.
Treble characteristics: “Concerning Hobbits” from The Fellowship of the Ring Soundtrack, “Set Fire to the Rain” by Adele, “Sarasate: Zigeunerweisen, Op. 20” performed by Anne-Sophie Mutter, “My Heart Will Go On” by Celine Dion, “Trumpet Voluntary in D Major: The Prince of Denmark’s March” performed by Clerkenwell Baroque String Ensemble, “Titanium” by David Guetta, “May It Be” by Enya, “Your Song” by Ellie Goulding, “Bring Me To Life” by Evanescence, “Blue Train” by John Coltrane, “How Long” by Kaskade, “My Life Would Suck Without You” by Kelly Clarkson, “Bleeding Love” by Leona Lewis, “Euphoria” by Loreen, “Execute Me” by Medina, “Our Love Is Easy” by Melody Gardot, “Come Away With Me” by Norah Jones, “I Will Always Love You” by Whitney Houston
Midrange characteristics: “Life Goes On” by 2pac, “Gangsta’s Paradise” by Coolio, “The Quiet Things That No One Ever Knows” by Brand New, “Vindicated” by Dashboard Confessional, “Hotel California” by the Eagles, “Come Fly With Me” by Frank Sinatra, “Moon River” by Frank Sinatra, “Welcome To The Jungle” by Guns N’ Roses, “Lips of An Angel” by Hinder, “Dark Blue” by Jack’s Mannequin, “Want To Want Me” by Jason Derulo, “I’m Yours” by Jason Mraz, “What A Wonderful World” by Louis Armstrong, “Suicidal Thoughts” by The Notorious B.I.G., “Radioactive” by Pentatonix, “Tears of the East” by Philip Wesley, “Canon in D Major” performed by Pimlico Quartet, “Californication” by Red Hot Chili Peppers, “Savior” by Rise Against, “Hallelujah” by Rufus Wainwright, “So Far Away” by Staind, “The Dream of You” by Tim Neumark, “River Flows In You” by Yiruma
Bass characteristics: “Sail” by AWOLNATION, “Brass Monkey” by Beastie Boys, “Monster” by DotEXE, “Dubstep Killed Rock n Roll” by Ephixa, “Deviance” by Excision, “Blood Red” by Feed Me, “I Can’t Stop” by Flux Pavilion, “Elements” by Fractal,“Concrete Angel” by Gareth Emery, “Aggressive Expansion” by Hans Zimmer, “Rise” by Hans Zimmer, “Time” by Hans Zimmer, “Limit to Your Love” by James Blake, “N*ggas in Paris” by Jay-Z, “Love Lockdown” by Kanye West, “Alive” Krewella, “Teardrop” by Massive Attack, “Remember the Time” by Michael Jackson, “The Island” by Pendulum, “Know Your Enemy” by Rage Against the Machine, “Full Force” by Rameses B, “1812 Overture” performed by Royal Philharmonic Orchestra, “Love is Darkness” by Sander Van Doorn, “Break Your Heart” by Taio Cruz, “Heartbeat” by Vicetone, “On My Level” by Wiz Khalifa, “Nuclear” by Zomboy
Imaging/Soundstage: “Book of Days” by Enya, “Caribbean Blue” by Enya, “Spirited Away - One Summer’s Day” by Joe Hisaishi, “Somewhere I Belong - Live in Texas” by Linkin Park, Hans Zimmer, “Now We Are Free” by Hans Zimmer, “The Thin Red Line” by Hans Zimmer, "Whispers In The Dark - Comes Alive Version" by Skillet, “Futile Devices” by Sufjan Stevens, “Words” by Yiruma
Speed and control: “Thunderstruck” by AC/DC, “Invincible” by Adelitas Way, “Flower of Life” by Au5, “The Diary of Jane” by Breaking Benjamin, “Can You Keep Up” by Busta Rhymes, “Bitterphobia” by Eminem, “Rap God” by Eminem, “Renegade” by Eminem, “The Might of Rome” by Hans Zimmer, “Elements” by Lindsey Stirling, “Enter Sandman” by Metallica, “The Magic Flute, K. 620: Overture” performed by Metropolitan Philharmonic Orchestra, “William Tell Overture” performed by Metropolitan Philharmonic Orchestra, “The Tsar Of Saltan, Op. 57: Flight of the Bumblebee” performed by Metropolitan Philharmonic Orchestra, “Last Resort” by Papa Roach. “Testify” by Rage Against The Machine, “That’s All She Wrote” by T.I., “Let’s Go” by Travis Barker, “Frum Da Tip Of My Tung” by Twista, “Kill Us All” by Twista, "X Japan
Dynamics: “Suite No. 3 in D Major” performed by the Pimlico Quartet, “Piano Sonata No. 14 in C-Sharp Minor I. Moonlight” performed by Bernhard Jarvis, “Axel F” by Harold Faltermeyer, “All Along the Watchtower” by Jimi Hendrix, “Eptesicus” by Hans Zimmer, “Dream Is Collapsing” by Hans Zimmer, “One Mic” by Nas, “Bohemian Rhapsody” by Queen, “The Suite Bergamasque: III. Clair de Lune” performed by Robert Einstein, "Art of Life" by X Japan
Low-level detail: too many great examples, will update if I notice an example that is especially nice
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)
- I wrote my sonic impressions prior to doing personal measurements.
- 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.
- 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
- 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.
- 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.
- 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!!
- For frequency response curve comparisons, I would recommend Tyll’s extensive database. Full list of his measurements found here. (credit: Tyll Hertsens at Innerfidelity)
- 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, 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.
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)
- 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.
- 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.PM-3 FR (Pink Noise 1/24 Smoothing) (Click to show)
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.K553 (White Noise 1/24 Smoothing) (Click to show)
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.
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.HE-560 FR (Pink Noise 1/24 smoothing) (Click to show)
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.LCD-X FR (Pink Noise 1/24 Smoothing) (Click to show)
More Comparisons: (links to my posts within head-fi threads)
- The HE-560 vs LCD-X vs K7xx
- Specific Song Analysis of differences between the HE-560 vs LCD-X vs K7xx (test track: Whispers In The Dark)
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.
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
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).
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
***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***