Headphone Reviews

Listening
Woot! I've got a new reference rig in the house! After spending some time with the AURALIiC Taurus MKII (John Grandberg's InnerFidelity review here) and reading about their Vega DAC on both Audiostream and Stereophile, I gave them a call to see if I could arrange a long term loan to use this gear as my reference rig. They agreed, shipped me a unit, and I'm currently tickled pink to have this uber-resolving rig to do my listening test. Thank you, AURALiC!

In listening test, I compared the AKG K812 to a number of other flagship headphones: Sennheiser HD 800; HiFiMAN HE-500; Audeze LCD-X and LCD-3. Since we're talking about headphones for audio pros, I also included the Focal Spirit Professional and NAD VISO HP50 to evaluate the flagship cans against some headphones with what I consider to have very good tonal balance.

Let's start with the good stuff: In a lot of ways I find the AKG K812 a fantastically balanced headphone with a great sense of space. The sound is a wide-open, coherent whole. I don't like to use the word "PRaT" (Pace, Rhythm, and Timing), but these cans have it. When I compare them directly to the HD 800, I feel the K812 more juicy and involving. Listening to Ricki Lee Jones' track "Dat Dere" the HD 800 sounded dry and a bit thin, though the treble response was cleaner and more articulate. Listening to the LCD-X with this track, the soundstage was markedly smaller and more closed in sounding with a more rolled-off treble response. The LCD-X did deliver a punchier and more dynamic listen than either can however.

Next I put on The Persuasions "Oh! Darling" (an all male acapella group), which is a lovely track to listen for midrange balance and tonal purity. Here again the AKG K812 did a fine job of rendering the voices. But a problem started to arrise when the main vocalist would sing loudly "need mee." The "e"s became quite hard sounding and significantly different from the quality of other parts of the vocals. When I listened to that particular phrase on the other cans the voice remained intact.

I have two tracks I use to test for harshness on a headphone. Tiger Okoshi's "Bootsman's Little House" where the trumpet entrance a few moments into the song is quite blaring but well recorded, and Pinback's "Non Photo Blue" which is a driving pop tune with crunchy guitars and bashing drums compressed significantly, but again well recorded. This is where the K812 Achilles heel became obvious. While the HD 800 can be annoyingly bright on these tracks, they also resolve the treble properly and the recordings retain their natural character. With the K812 these tracks became brutally harsh. Tiger's trumpet sounded as if it were being played with metal lips, and the crunching guitars snare hits of Pinback became piercing bursts of indistinguishable noise.

Bob James' "New York Samba" is typical of his highly produced pop-Jazz. At the 3:40 mark there's a very percussive high note played by the piano with lots of additional high frequency information coming from snare hits, tings at the center of cymbals, and a triangle all frantically moving along in this fast paced tune. The HD 800 was able to render all this high-frequency information allowing me to hear each instrument and sound as separate and identifiable. With the K812 I had a much harder time clearly hearing each sound, and I would often wince as the harshness and glare distracted me from the music.

Measurements (see next page) show the K812 as having serious problems with transient response and an area of elevated distortion between 1kHz and 3kHz. It seems to me these measurements are related to the problematic low to mid treble in listening. In my opinion, this confusion and harshness in the treble when lots of high-frequency information is present disqualifies them as tool for professionals as it obscures details, and disqualifies them as a high-end headphone for enthusiasts because it's unpleasant. I think audio pros will be much better served by the HD 800 when an audio microscope is needed, and by the NAD VISO HP50 or Focal Spirit Pro when tonal balance is desired.

Measurements also show a significant rise in bass distortion below about 100Hz. I have to say I didn't hear the bass of the K812 as being nearly as problematic as measurements might indicate. The HD 800 doesn't have nearly the amount of measured bass distortion as the K812 and bass level and extension are about the same on both cans relative to the mid-range, but in listening, the K812 sounds significantly warmer and the bass is more satisfying than the HD 800.

In the Context of Flagships
The AKG K812 is a marvelously musical headphone for small acoustic ensembles or when music doesn't encourage stridency, but when the music gets complex and having goodly amounts of treble information I think they fail to please. Likewise—and this is not news for enthusiasts—the HD 800 with it's rather cold and analytical presentation is somewhat problematic requiring a lot of effort putting together a DAC and amp, and/or modifying them to to bring out some musicality. Audeze planar magnetic headphones do deliver tighter bass and more punch, but they sound closed in when compared to the extraordinarily open and spacious sound of the K812 or HD 800.

To test for how frustrated I should be at the state of flagships I did mix in some listening with the Focal Spirit Professional, NAD VISO HP50, HiFiMAN HE-500, and Sennheiser HD 600. Sadly, I have to report that while these cans delivered significantly better price/performance ratios, they just didn't have that certain something that the high-end cans have. Finnesse or PRaT, call it what you will, they sounded dull and boring in comparison.

Oh, if only someone would build a flagship without serious flaw...

I'll keep my ear out.

Summary
The open, spacious, musical presentation of the AKG K812 is truly world-class with music that has a simple, mellow treble. But when the music has a complex treble, it's harsh uncontrolled frequency response between 3kHz and 10kHz reveals itself as a fatal flaw to my ears. Many will perceive them as simply highly detailed, and many will disagree with my take by putting more weight on the beautifully musical and spacious aspects of the K812. But I find them artificially bright compared to the true high-frequency resolution of the Sennheiser HD 800, which I warm up with careful component matching and EQ if I feel the need.

It's a shame. These headphones show some really excellent advancements for AKG, especially in regards to the earpads and comfort. So close, so close, and yet so far away.

Video

Resources
AKG home page and K812 product page.
Head-Fi threads here and here.
Steve Guttenberg and MuppetFace, arrgh!