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Review: Audio-Technica ATH-AD2000

post #1 of 82
Thread Starter 
Intro

The dynamic open headphones market is one of the most competitive in headphones, and it's thanks to this competition that's produced what I like to call the "terrible trio" of the AKG K701, Beyerdynamic 2005/06 DT880, and Sennheiser HD650. A trio indeed, and it'd have to take a beast of a headphone that can sit alongside those, or daresay, even above them. Enter the ATH-AD2000, the highest in Audio-Technica's line of circumaural open headphones, and their answer to the above competitors. At approximately $500 imported from Japan, the AD2000 costs considerably more than your average open headphone. Is it worth $500? Read on for the answer.

Equipment Used

Sources:
- Arcam CD73, over 700 hours
- CEC CD3300, over 200 hours
- Panasonic SL-CT579V, over 300 hours
- Asus Z71V laptop computer
Cables:
- Signal Cable Silver Analog, SilverMini, Analog Two, and Analog Mini interconnects, 150+ hours each
Amps:
- HeadRoom 2006 Total Bithead (from the laptop computer), ~150 hours
- HeadAmp 2005 AE-1, over 300 hours
- RudiStor NKK-01, ~40 hours
- DIY Millett Hybrid, over 700 hours
- Cayin HA-1A, ~50-60 hours

The ATH-AD2000 had approximately 350-400 hours of burn-in on them at the time of this review.

Test Music

- CDs
Andre Rieu - Tuscany (solo violin with orchestra)
Eva Cassidy - Songbird
Howard Shore - The Lord of the Rings: The Return of the King [OST]
James Newton Howard - The Village [OST]
John Williams - Superman: The Movie [OST] (London Symphony Orchestra, 1991)
Jewel - Goodbye Alice in Wonderland
Kevin Kern - Imagination's Light
Massive Attack - Mezzanine
Orbital - Middle of Nowhere
Peter Kater - Inner Works (orchestral)
Portishead - Portishead
Radiohead - OK Computer
Thievery Corporation - The Outernational Sound
Thievery Corporation - Sounds From The Verve Hi-Fi
The Crystal Method - Tweekend
The Prodigy - Fat of the Land
Zero 7 - When It Falls

- MP3s (ripped via EAC, encoded with LAME 3.90.3 at V2 VBR-NEW, range-limited to 96-256 kb/s, and played on the computer/Bithead combo - crossfeed was off)
Delerium - "Silence"
Massive Attack - "Live With Me"
The Crystal Method - "Acetone"
The Future Sound of London - "We Have Explosive"
Thievery Corporation - "The Supreme Illusion"
Zero 7 - "Spinning"

Review

- Bass

The AD2K's bass is strong, powerful, and remarkably deep. The lower range of bass is conveyed with an unprecedented amount of power and force that's literally unbelievable - unbelievable that it can come from a headphone! There's so much power in fact that bass can feel like it's being given a "Superman" kind of presentation - an overload of power and force, but never out of control that it becomes excessively boomy or bloated. It's a stark contrast from the polite bass of AKG's K701 or the boomy, subwoofery, almost out-of-control bass of Beyerdynamic's DT770. It's a very low-hitting, but also extremely forceful bass, that came most alive on The Prodigy's "Fat of the Land" - the strength behind even the lowest of lows was enough to cause a bass-gasm on every bass line.

Extension is nice and low, allowing the headphone to hit close to 30 Hz with little drop-off (as noted in the previous review of the DT880, I don't test below 30 Hz). Unlike some other headphones that have a recessed bass near 30 Hz, the AD2K goes straight down with close to full strength, allowing for a partial rendition of bass rumble. Of course it can't do true bass rumble (an area naturally for subwoofers), but the fact that the AD2K can almost render rumble is a testament to its quality of extension and signal strength at the lowest frequencies. Suffice it to say, the AD2K can unequivocally get those essential bass sweeps, phases, and rolls - for what a headphone can be expected to do, at least (it's not going to work miracles for bass-heads who want an overload). In fact, the AD2K is the first and only headphone I've heard that can actually begin to do justice to electronica by such artists as The Prodigy and The Crystal Method. That's still music designed for the subwoofer experience of course, but the AD2K just reaches down so well and serves it back up with so much power that it's almost ridiculous. Caveat emptor, however: the AD2K is able to give this kind of bass response only with a source, amplifier, and cables that can match its extension, and not many sources and amplifiers have this kind of extension (for cables any aftermarket/third-party/custom should do - Radio Shack grade cables need not apply). Admittedly I don't currently have an amp that truly does, but the NKK-01 gave a more-than-partial glimpse of its abilities. Make no mistake however that the AD2K has one of the best low-end responses I've heard to date - it's solid, weighty, full of power, visceral when needed, and all the extension that a headphone needs to have.

Quality of the bass is very good, if not quite up to the level of retrieving definable "texture." Specifically in the aspect of texture, the DT880 beats the AD2K - it just has more of it. That's not to say the AD2K has none though - it just has noticeably less in comparison. You can still tell that it's a kick drum opening Massive Attack's "Teardrop," it's just not as clear as it is with the DT880. As for low-frequency resonance effects, like on large drums, the AD2K easily gets those. The post-snap aftereffects of drum sounds are clear and given the right amount of dispersion so they can easily be heard.

Given the mostly electronic music I tested the headphone with, one might ask if the headphone is actually suited to electronica. I'm going to go ahead and say that it is, and the sub-genre doesn't matter either. It works great with IDM (Autechre, Photek, & Source Direct), trance (Orbital, Juno Reactor), techno (Leftfield, Fluke, Underworld, The Chemical Brothers), punk-rock electronic (The Prodigy), and ambient.

Components most conducive to increasing the perceived bass: CD3300, NKK-01.

- Mid-bass

Mid-bass has its own section in this review because it's distinctive enough to mention on its own - it's a very nice mid-bass, though not entirely true to the original sound. The power that the bass has continues up into this region, giving bass-heavy music a high amount of slam. Music with the right bass rhythm can make for a very headbang-worthy experience. There's a bit of a snap & verve to it, though not as much as there could be. It does makes up for it though in overall power & strength - one could say this headphone is more of a "thumper" and "banger" than a "snapper." That might be asking too much though, as most headphones don't give a snappy mid-bass.

Comparing the bass/mid-bass presentation to the ATH-A900, signal strength on the mid-bass overall is evenly matched with the lower frequencies - it's fast, tightly-held, and very hard-hitting. In contrast, mid-bass on the A900 is held back from matching the lower frequencies - not that it's noticeably recessed, but its extension is more noticeable than its slam. The AD2K has more impact and a much better speed that work for it in especially electronica.

Components most conducive to increasing the perceived mid-bass: HA-1A and Millett Hybrid.

- Mids

The AD2K's mid-range is probably its single most noteworthy aspect - it's very lush and full, much moreso than any other typically "warm" headphones. Of all the headphones I've heard, the mids are most similar to AKG's K240S and K271S - very warm, very full, lots of body to instruments. Unlike those AKG models though, the AD2K doesn't overly emphasize the general lower mids, and it brings a much better separation - instruments don't just sound like they're being played, they sound real and like they're in the midst of your presence. You don't feel like you're missing any component of an instrument's sound or that any part of an instrument's sound is being bloated. The mids almost border on being thick, yet sound very natural and real. It's a huge contrast to headphones like the DT880 and K701 - there's a much bigger mid-range response here that provides an intangible sense of being with the instruments instead of merely listening to them. The AD2K seems to just dig deep into an instrument's lower range (if it extends into the mid-bass crossover frequencies) to really bring out the lower component of the sound that so many other headphones miss. It's a very integrated response as well, so no one part of the mid-range sounds obtrusively emphasized.

Unspecifically, the AD2K brings out a mid-range response that above anything else can make you feel the music, the power within it, and the passion that's stored in a performance. In this way it sounds like a window into the music - it's fully able to give an incredible soul-stirring, heart-wrenching rendition that's unlike anything else. And if vocals are supposed to be breathy, the AD2K gets it all, right down to the saliva if it's there on the recording! Lung power is especially noticeable with it too - Annie Lennox on "Into The West" from the Return of the King soundtrack, Jewel when she really gets going, Eva Cassidy on "Songbird" - the AD2K gets the full power of their voice whenever they sing out.

As the frequencies increase throughout the mid-range, the AD2K increasingly shifts the presentation forward, resulting in a definitively forward sound around the human vocal range. Male and female vocals are very forward, sounding like they're right in front of you. There's a slight unnatural effect here though, making it seem like vocals are being "channeled" or "directed" towards your virtual position in the soundstage. It makes for a very engaging, personal listen, but something about this forwardness sounded a bit forced.

The forward presentation continues up past the vocal range into the upper mids, which of course affects a range of instruments, mostly string-based ones. String-based instruments tend to sound more like their lower-frequency component than their upper-frequency component - violins, for example, are conveyed with the appropriate body and resonance, but the treble part of their sound doesn't really "sparkle." Not that it matters though, as they sound great without that treble sparkle.

Components most conducive to increasing the perceived mids: HA-1A and Millett Hybrid amps, copper cables.

- Highs

Not that the AD2K doesn't have good treble, because it does - it just doesn't have a treble-oriented signature, as its focal point is on the mid-range, not the highs. That said, the highs are mostly flat on the AD2K - there's no noticeable emphasis anywhere in this range, and there's no noticeable recession either. It's just that compared to the upper mids, the highs can seem recessed, but that's not the case as the upper mids are simply emphasized. Extension is very good here, it runs right up to 16 kHz with ease and even beyond with no obvious roll-off. Signal strength at the extreme is also very good, much better than even the DT880 - it easily catches piercing sounds, high harp runs, and upper harmonics, and it does this without sounding painful. (Also, there was never any sibilance from day one.) For the first time, the headphones were challenging my hearing rather than the other way around. So it's an excellent extension, no need to worry about hearing the highest notes from your recordings. Another caveat emptor here - naturally, its audible extension will depend on the source, amplifier, and cables being used. The AD2K scales with component upgrades and will take full advantage of a source and amp that have crystalline highs.

Despite the highs being relatively flat compared to the mid-range, orchestral music works surprisingly well on the AD2K, and probably even better than on either the K701 or DT880 for most people, as it gives a much better picture of the natural resonance that the orchestral instruments have. The non-string sections such as brass and woodwinds are fully matched up against the strings, unlike the K701 and DT880 (which both give the strings emphasis over the other sections). And the emphasis works to great effect too - the AD2K seems to capture more out of the other sections, like woodwind players pausing for breath (or struggling for breath), or the valve movements from a brass player.

Components most conducive to increasing the perceived highs: NKK-01, AE-1, silver cables.

- Attack & Decay

The AD2K's attack easily trumps the attack on the K701, DT880, and HD600. Not even a question here. It's faster and stronger than any of those three - so swift that it can separate an impact sound from the impacted object's sound, if there's a delay between the two. It's like an active monitor constantly watching and waiting for notes to enter the airspace and then latching on to give the needed kick. Like the ATH-ES5 and ATH-A900 before it, the AD2K also does an excellent job on percussion instruments - separating them from opposing layers, giving them the right amount of impact, and giving a blackness between fast notes. The AD2K isn't big on detail retrieval either so its fast attack helps it pick up quick sounds that might otherwise slip past it, like shrill notes, trickle effects, or anything else that might jump out of the soundtrack.

Decay is a bit on the fast side, but it's not too fast that it doesn't allow sounds to exit back into the airspace - as mentioned above, the AD2K does get lower-frequency resonance, usually from drums like timpani and kettle drums. Decay is about the same speed as on the K701, a little bit slower here though - it gets marginally more on cymbal and double-cymbal aftereffects, enough that a deficiency isn't very noticeable.

- Detail & Resolution

The AD2K isn't a detail-oriented headphone, certainly not on the level of the DT880, for example. It still manages a level of detail about equivalent to the K701 though - it's easily able to get the clicks, hisses, and pops of an analog recording, and the subtle details packed into digital recordings. And the AD2K sounds like it's not even trying when retrieving these details, it's done completely effortlessly, in contrast to the DT880 which can sound like it's trying. However, due to its overall intimate sound signature, flaws in a recording, specifically in distortion and over-compression, tend to not sound like they're part of the recording and come across more as a flaw of the headphones. This results in a wrong picture of where the flaws are, clearly there could have been much better separation in this aspect.

Resolution is very good, it holds layers intact very well, regardless of how many are going on. It doesn't place layers in their own sound space like the K701 does, but it does seem to widen the field as more layers are added, allowing for a sense of "breathing room" in the virtual soundstage. Overall clarity however isn't a strength of the AD2K, as parts of the mid-range can sound a bit "veiled" especially for those who aren't used to a warm & full mid-range.

- Soundstage

The AD2K has a nice, wide soundstage that seems to localize the music in front and around you - except for singers of course, who sound like they're right in front and way too close. Perceived distance is like a few rows back, dead center. It's also a little bit airy and gives a nice sense of space to the music. Unlike the K701 where the airspace feels like a void going on forever, the AD2K's airspace feels like it has an end - you can almost hear where the walls are, in fact. So the airspace is very definable, but it's large enough that music never sounds closed-in and claustrophobic.

There's also a very nice "dispersion" kind of effect that handles complexity and routes layers to their own position in the soundstage. Stereo-channel separation is very clean and helps provide a nice 3D positioning that's done very convincingly. The resulting sound field is very horizontal, very realistic of where instruments/performers normally are in real-life. Orchestral music in particular benefits from this, the violins always sound like they're coming from the left and the brass & woodwinds like they're coming from the back, with the basses and cello on the right. As a detriment to orchestral though, it tends to not sound very epic and big - primarily due to the lack of treble sparkle, but it's also because of the limited airspace.

- Physical Aspects

The AD2K isn't that small for an open headphone, weighing a little more than 250 grams. The earcups are also rather large. It's a nice, secure fit for those who have a smaller head, but large heads will likely feel pressure on the ears from the earcups - frequent breaks may be necessary to avoid soring up the ears.

Cosmetically, it's a very nice-looking headphone. All-black, with a combination of metal and plastic, and magnesium on the wireframe support. The cloth earpads don't have much internal padding and it's been reported that small ears will probably touch the drivers. To alleviate this, you will probably need to stuff the earpads - search for previous threads for suggestions.

The 3D "wings" are flimsy but as long as they're not abused, the headphone can take a beating and keep on ticking. Solid construction everywhere, much sturdier than the cheap-feeling plastic of the K701.

- Amplification

At 40 ohms, the AD2K can be easily driven even from the headphone jacks in DAPs and PCDPs. It's actually quite forgiving of such sources as well, as long as you don't listen too critically. However, the AD2K benefits significantly from an external amplifier and effortlessly scales up as amplifier quality increases. It's easy to hear differences between amplifiers with the headphones. However, since it's not a transparent headphone, a transparent amp is highly recommended. Tubes work well with it but it clearly pairs better with solid-state designs so the already-lush mids can remain largely unaffected.

As far as recommended amplifiers go, anything that's solid-state works great with it. Since Audio-Technica tailors its amps for use with its own headphones, one of their amps such as the HA5000 (or the HA20 for those on a budget) is probably the ideal. It does seem to have better synergy with brighter amps that can provide more crispness and detail over anything else, but it also works very well with amps that provide a more complete, balanced sound.

A note about the Bithead here - the AD2K worked great with it set on Low Gain. Crossfeed wasn't necessary, and didn't seem to do much either. The resulting sound from the laptop was eargasmic, very good clarity. MP3 files sounded very good on it.

- System Synergy

Though the AD2K might be able to be used with a DAP or PCDP, it increasingly benefits from upgrades anywhere in the equipment chain. It's very dependent on source, especially at the extreme ends of the frequency spectrum, and the amplifier type and quality will make or break sound quality. It's naturally least dependent on cables, but even those can make a surprising difference.

A source with a warm signature isn't necessary at all, as long as it has good extension in both directions and strong clarity. I'd suspect the AD2K would pair best with a very detailed source, and one with lots of bass but even more highs - essentially, a treble-oriented source. For an amp, I highly recommend a solid-state that can put out enough current to meet the AD2K's 1-watt max input power requirement. Class A-biased amps seem to work better with it than amps that aren't. To best maximize the sonic features of the AD2K, the op-amp should be as neutral as possible in the mids, very extended in the bass, and have emphasis at the top-end. Finally, silver cables are recommended but should probably be used with caution - the one I own doesn't have a harsh top-end, but other silver cables might.

Conclusion

In case you couldn't tell by now, I've been highly impressed with the AD2K. It handled every genre I threw it at - alternative, trip-hop, electronica, classical, jazz, rock. The genre it did least well with is rock, as to be expected - it just didn't give the transients and bite that make Grados so much better to use to listen to rock. That doesn't take anything away from it though - it's the most versatile headphone I own, and it blows away my other headphones. The difference to me is HUGE - it really is just that much more involving and intimate. The K701 and DT880 sound like tin toys compared to the AD2K. It's a lean, mean audio machine that can provide the next level in giving you that elusive transcendental experience for your music. Some have called it an "x-factor" and I agree, there's just something about it that makes music such a pleasure to listen to. For me, the $500 was worth it. Only you can decide for yourself if that's an amount you're willing to spend. My best advice is to ask yourself if you think you could ever afford to spend the money for the headphones along with the requisite source, amp, and cables. I answered yes to that question a few months ago and found my audio nirvana, and the path to the end of my Head-Fi journey!

If I had to sum the overall sonic signature of the AD2K into a neat list, it'd be:
- Fantastic low-end with TONS of power and force. DT770 who?
- Full, lush, to-die-for mids - if they don't enrapture you, you're not human!
- Clean, extended highs without a trace of harshness, treble sparkle be damned!

It's just a supreme audio machine of pleasure guaranteed to give an eargasm! Go for it!


Post #2000!
post #2 of 82
Awesome review dude.
post #3 of 82
Excellent review. You covered all the bases thoroughly. It sounds to me you found these headphones more or less perfect too! The only problem is that they're quite expensive (+shipping, tax, etc..) Thanks.

EDIT: the most impressive aspect of these headphones from your review was your description of its soundstaging. Does it really have such rediculous realism to it?
post #4 of 82
Great review. I'd say the ad2k is a hybrid of the HD600 and RS-1. It really takes the best of both. As a trumpet player, i feel that they reproduce the best brass sound i've ever heard from a pair of headphones.
post #5 of 82
Oh, add some pictures to this and I'll nominate this review to be moved into the "Featured Full Reviews of Headphone" section!
post #6 of 82
Thread Starter 
Hey, who put the review in Featured Full Reviews already? I wanted to sit on 2000 posts for at least a few hours!

I would've taken pics milkpowder, except I don't have a digicam right now. But very soon I'll have a new one, I can put up pics then.

Quote:
Originally Posted by milkpowder
Excellent review. You covered all the bases thoroughly. It sounds to me you found these headphones more or less perfect too! The only problem is that they're quite expensive (+shipping, tax, etc..) Thanks.

EDIT: the most impressive aspect of these headphones from your review was your description of its soundstaging. Does it really have such rediculous realism to it?
I thought I raved more about the mids than I did soundstage. Its soundstage is very nice, a lot more defined, and IMO leagues better than the K701's soundstage because it's not as blobby and airy.
post #7 of 82
Quote:
Originally Posted by Asr
Hey, who put the review in Featured Full Reviews already? I wanted to sit on 2000 posts for at least a few hours!
Uh... that would be me!

Nice review, and one that I happen to agree with in all principal parts. Like you, I've compared the AD2000's to the 'usual suspects' of <$500 headphones (i.e., HD650 with a variety of aftermarket cables, K701, and DT880, all of which are excellent headphones in their own right), but have a quite clear and convincing preference for the AD2000's.

I've said this many times before, but the AD2000's simply pull me into the music and make me forget about the 'sound' as such or that I'm even listening to headphones to begin with. About the only other dynamic headphones that do this for me are the R10's and L3000's. To me, this is an extraordinary feat for a $500 headphone.

There is nothing about the AD2000's sonic signature or overall musical presentation that calls undue attention to itself. When you need bass, you're got bass, and lots of it, as clear as can be and without a trace of muddiness. When you need treble extension, you've got it, and wih no trace of simblance (at least not to my ears). And mids? Oh, the glorious, ever present mids! You're right in that vocals are pulled forward in the headstage, but I kind of like this effect because it increases my sense of involvement with the music as a listener. It's not artificially forward to the point of being annoying or drowning out other aspects of the music. It's "just right" from my perspective.

Are the AD2000's perfect? Not at all, as there is still a trace of the famous AT coloration in the mids. It's a similar coloraton to what I've heard with the W100 and/or W1000, but not anywhere near to the same degree. For the AD2000's, this translates as a "fun factor" and IMO is all good. For the W1000's in particular, this same - but much more pronounced - coloration is what kills the joy of listening to them. So nothing is perfect, but for $500 or less, I've not found better.
post #8 of 82
Wow, impressive review.

I don't think there's much plastic in the AD2000, other than the 3D Wings.

It's the second lowest in the line of AT open headphones? I believe it's currently the top headphone in the AD Series, and the highest ranked AT open headphone. The only current production AT ranked above the AD2000 is the closed W5000.

A photo:

post #9 of 82
Great review!

Great photo, too, Elephas.
post #10 of 82
Thread Starter 
Oh well, it's time to truck on to the next post count milestone now anyway.

Quote:
Originally Posted by Elephas
Wow, impressive review.

I don't think there's much plastic in the AD2000, other than the 3D Wings.

It's the second lowest in the line of AT open headphones? I believe it's currently the top headphone in the AD Series, and the highest ranked AT open headphone. The only current production AT ranked above the AD2000 is the closed W5000.
Er...oops. I can't believe I made those mistakes, I must've been more tired than I thought last night when wrapping up the review. Fixed now, would appreciate if a moderator updated the copy in the Featured Full Reviews too, thanks.
post #11 of 82
Quote:
Originally Posted by nabwong
Great review. I'd say the ad2k is a hybrid of the HD600 and RS-1. It really takes the best of both. As a trumpet player, i feel that they reproduce the best brass sound i've ever heard from a pair of headphones.
I can't wait to hear this today
post #12 of 82
Quote:
Originally Posted by Wmcmanus
Uh... that would be me!

Nice review, and one that I happen to agree with in all principal parts. Like you, I've compared the AD2000's to the 'usual suspects' of <$500 headphones (i.e., HD650 with a variety of aftermarket cables, K701, and DT880, all of which are excellent headphones in their own right), but have a quite clear and convincing preference for the AD2000's.

I've said this many times before, but the AD2000's simply pull me into the music and make me forget about the 'sound' as such or that I'm even listening to headphones to begin with. About the only other dynamic headphones that do this for me are the R10's and L3000's. To me, this is an extraordinary feat for a $500 headphone.

There is nothing about the AD2000's sonic signature or overall musical presentation that calls undue attention to itself. When you need bass, you're got bass, and lots of it, as clear as can be and without a trace of muddiness. When you need treble extension, you've got it, and wih no trace of simblance (at least not to my ears). And mids? Oh, the glorious, ever present mids! You're right in that vocals are pulled forward in the headstage, but I kind of like this effect because it increases my sense of involvement with the music as a listener. It's not artificially forward to the point of being annoying or drowning out other aspects of the music. It's "just right" from my perspective.

Are the AD2000's perfect? Not at all, as there is still a trace of the famous AT coloration in the mids. It's a similar coloraton to what I've heard with the W100 and/or W1000, but not anywhere near to the same degree. For the AD2000's, this translates as a "fun factor" and IMO is all good. For the W1000's in particular, this same - but much more pronounced - coloration is what kills the joy of listening to them. So nothing is perfect, but for $500 or less, I've not found better.
Would it be fair to say that the AD2000 is in a different league to the big three (HD650, K701, DT880)? Is there any aspect of the AD2000 that one of the big three actually does better? Is this another case where there are other cans that can do better in certain respects, but the AD2000 is better and different in so many ways that they are better overall? One more Is this the best open-air headphone that is currently in production?
post #13 of 82
Great review! And just what I wanted to hear while I'm waiting to get my own pair.
post #14 of 82
Fitz, you will get it soon:-) In the meanwhile read all the great and well deserved AD2000 reviews.

Quote:
Originally Posted by Fitz
Great review! And just what I wanted to hear while I'm waiting to get my own pair.
post #15 of 82
Great work on the review Asr!

Totally agree about their synergy with solid-state amps.

Recently bought AD2000 and Millet Hybrid from different forum members. HF-1 is now permanently attached to the Millet and AD2000 pairs fantastically with a SR-71.

Both combos are more satisfying in their own way than the SR-71 + HF-1 was
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