Before you get all excited about some all new Audio Technica headphone, the AD2000MKIV is a major modification of the AD-900s. They have AD2000 drivers in them, a Pro700MKII driver plate (basically the front ring that is around the driver unit and screws into the headphone enclosure-the earpads wrap around it), Beyerdynamic Gel Earpads, some modeling clay and putty, a custom bent headband (no, I didn’t buy it or anything, vise grips and my hands did all the work), and an AD900 base chassis.
Below are the details on how I arrived at MKIV.
Timeline (Click to show)
MKII was basically the AD900 with AD2000 drivers in them with a bent headband, the stock earpads and the Pro700MKII pads inside them (they fit rather well, too. Think of it as an evolution of the rope mod that’s popular on the AD series). Doing this increased comfort, bass impact, and evened out the sound a bit. What was wrong with it? Bass. I am a pretty big basshead when it comes to music, and while the MKII would probably satisfy your average headphoner out there, it wouldn’t satisfy your average basshead, and most definitely not me. So, I got a bit curious and put my noodle to work.
I ripped the beyer gel earpads that I rigged on my Pro700MKII (check my Pro700MKII bass mod for how I did it. Info is in my sig link), and put them on the AD900 enclosure. After trying to work them out, I concluded that there was not enough clamp on these headphones to get a good seal around my head. I put some cotton underneath the pads to make them thicker, but it still wasn’t good enough, since the bass sounded really hollow, flabby, and had a nasty reverberation effect. So, I bent the headband even more. That fixed it. Well, most of it. I still had a bit of reverberation action going on, though much less than before. So, I was starting to get the bass that I was envisioning. Now, this headphone stayed at MKIII for a good few months (over three, I think). I really liked the sound signature (basically the same as the AD2000, but with a whole lot of bass, a bit less air than stock, a bit recessed midrange and treble, and better comfort.
Back when I was making MKIII, I was fiddling around with the Pro700MKII ring to see if it could fit on the AD900 enclosure. While the ring did “latch” on to the elevated side of the AD900’s ring, the negative slope (made to conform the drivers to your head) really made some gaps between the driver and the ring. At the time I couldn’t think of a way to make it fit, and I thought that doing so would really mess up the sound signature (like sucking out the midrange and treble, and making the bass flabby). When I did a temporary rig up, that was indeed the case. Fast forward to 6/9/2013, and I decided to give it another try, but with a twist. I got some clay laying around the house (the ones that look like rectangles wrapped up in clear plastic; you can buy them from your local arts & crafts store), and pressed it around the circumference of the driver, where the white felt material is at. Before, when I put the Pro700MKII ring on the headphone, there was a gap between the driver face and the ring, making the sound leak out badly. The modeling clay sealed up those gaps brilliantly and offered another advantage: dampening mechanical vibrations. The AD series have a remarkably thin headphone design, and that makes the bass really rumble the frame and cause some unwanted reverberations, especially if you don’t have a good seal around your ears. The clay absorbed those vibrations beautifully, and it offered a more coherent frequency range, especially in the lower registers.
The problem with MKIII was that the cotton underneath the earpads had a tendency of getting wedged out from underneath the pads and lay around the circumference of the driver as a result. This was due to the clamping force squeezing the cotton out from underneath the pads. While this didn’t do much to the sound when I was listening to MKIII at the time, MKIV really opened my eyes on how much this driver is capable of. Having an air-tight seal around my ears allows the most transparent transition from the driver membrane to my ears. It seals so well, in fact, that if I even open my mouth, the pressure change affects the driver’s performance, and it kind of “mutes” the sound a bit. Then it comes back with an attenuated-like sound signature, and finally equalizing out the way it used to be a couple seconds afterwards. All of the vibrations the drivers produce are reflected inside the chamber that the ring and the earpads created, so my ears hear basically everything that the driver creates without any obstructions or outside interference. The fact that I basically have dead air inside the headphone when I put them on further validates that.
So, what does it sound like, you may ask? Quite nice. I haven’t had the pleasure of truly listening to any expensive headphones, just a couple of low-end headphones like the M50s and the Pro700MKII, but I did, however, listen to the LCD-2 for a regrettably short period of time. Unfortunately, I don’t feel confident comparing my headphones to the LCD-2 solely because I didn’t listen to them long enough, and I auditioned the LCD-2 when my modified Pro700MKII was my primary headphone (the AD2000MKIV wasn’t even thought of at this point in time). If I may throw some words in the air, I would be willing to bet that my AD2000MKIV would sound pretty close to them (a part of me wants to say that they would sound better, from an objective standpoint, of course).
The best part about the AD2000MKIV is that it retains everything that made the AD2000 what it is (midrange, air, soundstage), but it improves everything that it lacked (bass, comfort, transparency, imaging), and it even improves the stuff that it was already good at. Let’s see if I can put these changes into perspective.
Well, before I get into the good stuff, here’s my setup:
Audio Setup (Click to show)
Computer (~+10dB in the bass, and the treble and midrange being equalized for neutrality. Check the pics further down). I’m using Foobar2k with Wasapi, Resampler (Sox), and electric-q posihfopit edition.
Toslink-in into receiver (+10dB in the bass on the receiver)
L/R Speaker out (that means the speaker amps are being used, not the phono-out)
Custom speaker wire->RCA female adaptor
Male RCA to female 1/4mm headphone-in
The only downside to this setup is I get a bit of hiss from the speaker outputs. Maybe if I use a resistor of sorts, I can reduce it, but I’m not sure where to start or how to do it. I can’t hear the hiss when I’m listening to music at a low-medium volume level, so it isn’t that big a deal.
As you can see, the settings aren't at default, but I was trying to attain a neutral sound signature with heavy bass emphasis, so the equalization was necessary.
Alright, now on to the sound characteristics:
Bass (Click to show)
Most definitely the hardest hitting headphone that I’ve ever heard. It’s heavy, it’s authoritative, it’s deep, it’s clean, it has a startling amount of separation, and it can seriously damage your ears. I mean, it slams so hard, it blurs your eye vision, depending on how loud it is and at what frequency. The blurring effect is like difference of having 20/20 eye vision and 20/30 eye vision (I’m able to say this because I have ~20/30 eye vision, and it’s strikingly similar). I thought my modded Pro700MKIIs blurred my vision when I primarily listened to them…hah. It’s like comparing a base Corvette to a Zonda R. The amount of separation the bass has from the rest of the frequencies is simply astonishing (something the pros aren’t that great at). Even when I blast the volume out, and thus creating crazy SPL amounts, the bass performance never falters, and it never compromises for anything lesser than its superior majesty. It stands straight and proud, without any doubt in its mind that it’s completely badass.
The main reason why I’m getting such large SPL amounts is because I’m using the speaker outputs on my receiver. The headphone-out on my receiver simply didn’t offer enough juice to properly control the driver at low frequencies (it still does a damn good job, though, better than a Schiit Magni). Things like the FiiO E17 do a good job at powering these phones, but it offers nowhere near the amount of power a proper receiver’s speaker-outs are capable of, and that power is needed if you want to have a lot of bass. My receiver is rated at 90w@8ohms. Whatever that translates to in 40ohms is going to my headphones (AD2000 drivers have a 40ohm impedance). The other reason why I’m getting so much sound pressure is because of the way I modified the headphones. The IEM-like seal, and the direct transition of sound from the driver to my ears really allow to bass to bloom. Maybe I can say it’s like having an oversized IEM on your head…or should it be called OEM? No, not that OEM.
The closest “real-world” thing that I can compare the bass to is a good car subwoofer setup. No, I’m not going to have ear bleeding bass, and I won’t feel the impact all over my body, but the punch and oomph that you get from a comfortable volume (or even a louder than usual volume) on a car sub is the closest thing that I can think of that my headphones compare to. Well, I guess the easiest way I can put it is that the AD2000MKIV can have so much bass that they can make your ears hurt. I really have to be weary on how loud I’m listening to my music.
Unfortunately, the drivers can't take a lot of power, and with powerful amps like mine, the drivers start to peak out. I actually blew a couple AD2000 drivers on accident.
Midrange (Click to show)
Well, it’s basically the same as a stock AD2000, but with increased air and transparency. If I may get a bit creative, it sounds more aggressive, textured, and extended. To my ears, it sounds neutral, if not a bit forward after it’s equalized.
There is a dip at around 3kHz, and a peak at around 4kHz. This makes sounds like female vocals sound a bit dry and artificial. Once those are ironed out, you get a very natural and lush presentation.
Treble (Click to show)
After equalizing it, it’s the most natural treble I’ve ever heard. Before equalizing it, there were some nasty peaks in the frequency band that allowed the treble to sound a bit artificial to my ears. If you’ve listened to the AD2000 long enough without eq’ing the peaks and dips, you probably won’t notice it (or you liked the way it sounded and left it alone), but after you iron the peaks out with an equalizer, it sounds awesome (series of peaks and dips in the 10kHz-14kHz range, check the pics further down for an illustration). Before the equalization, sounds like cymbals and drums sounded dry and a touch too bright. Now, they sound lush, natural, and easy on the ears. As far as how the MKIV sounds compared to a stock AD2000, it’s basically the same as the advantages the midrange had. One thing that I did notice almost instantly was how sharp it sounded. Not sharp as in harsh or sibilant, but the sharp as in razor sharp. The amount of extension, separation, air, and “chop” in the treble is breathtaking. It’s definitely more revealing than a base AD2000.
Comfort (Click to show)
Definitely more comfortable than a stock AD900. I can wear these headphones all day long (over 8 hours) and have no signs of fatigue. My ears do get sweaty after a while, since, first of all, I’m greasy by nature, and because my ears aren’t able to get aired out because of the seal blocking outside air.
The wing headphone design feels very good on my head, and instead of having one large strip of compressed hair (headphone hair) due to a headband, I have two small depressed spots on my head instead, due to the wing design. It’s nothing a quick shower can’t fix, though (or a haircut). After a few minutes of wearing the headphones, they like to disappear from my head, which nicely compliments the soundstage performance.
Soundstage (Click to show)
This part is the hardest part to type about. Let’s see if I can illustrate it for you guys.
The first thing that I notice when I’m listening to the music is the frontward projection. It’s like there’s a channel dedicated to the front soundstage or something. Atmospheric effects like clapping, atmospheric breathing sounds, echo-like sounds, and electronic effects tend to project really far in front of me. Just how far? Well, it depends on the song. Some songs, the frontward projection can be right in your face, while on other songs it can sound like I’m in an auditorium.
The width is very good too. If I recall correctly, the author of the Headphonia review on the AD series said that the soundstage on the AD series headphones are pretty wide, so I guess my AD2000MKIV improves on that. Then again, it’s pretty hard to determine how wide it is. On some songs, vocals can sound like they’re inside my ear canal. On other songs, vocals can sound like the person/people is/are standing next to you and sweetly singing to you, and on other songs, the vocals make me jerk my head around because I swear I felt their presence in my room. Then again, it’s more dependent on how the artist who made/mastered the song than anything. They could have added some reverb and stuff to the music to emulate a larger sound field, or not.
Now onto soundstage height. Like the width, it’s pretty hard to determine how high it is (it really does depend on the song), but on some songs, it can be as vast as the frontward soundstage projection. It isn’t like all of the music is sitting on a flat line running around my head. Some stuff sounds higher than other stuff, some lower, and some in the corner of my eyes. So, although I can’t really determine the height, it’s high enough to give me a 3d representation of the music I’m listening to, which is high enough.
So, the conclusion for the soundstage part: It depends. It can be as vast as an ocean on some songs, and claustrophobic on others. Most of my songs fall right in between those extremities, usually leaning towards the larger side (I listen to lounge music, deep house, and ambient music mostly). I will say that the soundstage performance is very satisfying, and I usually don’t finding myself wanting more, which is pretty surprising for me since I’m a soundstage freak after I’m a basshead. The best way I can put it is that the soundstage sounds transparent. The headphones fully convey what the artist of the music was trying to express, and then some.
Random Soundstage Rant (Click to show)
In my opinion, there are two ways to implement a good soundstage. The first way is the one implemented in my headphones, where you have all of the information coming from the drivers going directly to your ears, so you have a more accurate soundstage based solely on the sound coming from the drivers, like the Beyer DT990 or the LCD-2. Then, you have another method which involves using an open-air type method that lets the sound leak out the headphones into the air around you to give you a sense of a large soundstage. The latter method is more popular on headphones like the Sony MDR-MA900/MDR-F1, with their rather large opening in the rear of the headphone, the HD800, which has a silver mesh material between the driver and the earpads so the higher frequencies can breathe, and the AD series, which uses a very weak seal paired with a light clamping force to allow the sound to leak from the headphone. While that method does give you a good representation of a soundstage, there is one fundamental flaw with it: it hinders bass performance. If you allow outside air to interfere with the lower frequencies, it will really mess it up, especially if you don’t have a good seal from the earpads. The result are attenuated/rolled off lower frequencies, very minimal amounts of impact, and a flabby-like sound (all of these are to varying degrees depending on how the headphone implements an open-air soundstage).
You see, open headphones are usually branded by having poor bass performance because of a combination of poor sealing earpads, light clamping force, and various openings for sound to leak out (depends on the headphone). Closed headphones usually have a tighter clamping force paired with better sealing earpads, so you have better bass performance. Take the Fostex TH-900 for instance. I’ve never heard them, but the frequency response measurements do not show the lower frequencies being rolled off. This is because the earpads and the clamping force allow a proper seal around your ears so that the bass is properly represented.
Alright. End of rant. If someone wants to talk more about that, or debate on it, then feel free to reply. I’m not always right, and I love learning about this stuff. Now, on to the pics. Here ya go:Pics, 56K Warning (Click to show)
Here, you see the peaks I was talking about. Contrast it to the following picture (the frequency response of a base AD2000), and you’ll see why I say it’s neutral. Since I’m using modified headphones, the frequency characteristics should be a bit different versus a base AD2000, but it shouldn't be by a large amount. Even if it isn't neutral, these settings sound great. And of course, I bumped the lower frequencies up a small amount to satisfy my bass crave (I actually equalized the bass by trying to get the 20Hz-100Hz range to have the same perceived volume intensity throughout that range).
Here’s the contrasting picture. You see my eq isn’t perfectly the opposite from this one, but it’s close enough, and it sounds great where it’s at. Just in case anyone was wondering why there is a roll off starting at around 100Hz, it’s because the earpads let the sound escape, thus lowering the lower frequency’s SPL.
Now the only reason why I’m throwing this up there is because there’s a problem with my drivers. The right channel has a bit more bass quantity than the left side (not all drivers are created equal), the left channel distorts quicker on some frequencies (so I have to balance both drivers out), and some oher minor defects. In order to “fix” it, I just used a parametric equalizer to balance out both channels. This isn’t something a gain adjustment can totally fix, unfortunately. It’s an inherent problem with the driver, but this allows it to be close enough. Fortunately, the air-tight seal seems to fix most of the problems the driver has. On MKII and III, the left channel would sound flabby and distorted at higher volume levels (mostly between the frequencies 30Hz-50Hz), while the right channel would stay tight and precise throughout. I do a bass test on my headphones by listening to clips of frequency ranges from 20Hz-100Hz (10Hz increments), and equalize the bass depending on the quantity of it, and how much the driver is able to handle, as shown in the first pic.
Here’s the display of my stuff. I have channel mixer on there for whenever I want to use Dolby headphone. It’s like putting the soundstage on steroids, but you get an aggravating reverberation effect in return (even on DH1). It sounds good on some songs, but on others, the bass sounds bloated, and the dynamic range doesn’t sound right. I have my Dolby headphone settings stored on the channel mixer for Dolby headphone, and it I were to remove it from my active DSP list, I’d lose my settings. That’s why I leave it up there and set it to bypass. Just for those wondering, I prefer Channel Mixer to FreeSurround. You get less of a reverberation effect, and the sliders don’t lag.
Here are my resampler settings. Like Channel Mixer, I leave this up for Dolby headphone. The DH wrapper doesn’t support anything above 48 kHz, so I leave it at that. Since all of my music is either 44.1 or 48 kHz, it doesn’t hurt.
And here’s my sound settings from windows. I have to put it on 24/96 or else when I’m listening to YouTube videos, or am on any other type of streaming website (soundcloud, grooveshark, etc.) it will sound aliased for some reason.
Here’s the picture of the modeling clay I put on the headphones. You’ll see the little impressions the Pro700MKII ring made on the clay. If you look at the pictures closely, you’ll see where I was talking about when one side of the are around the drivers is elevated, and the other side is more in line with the extreme outer area (the area the clay isn’t on). On my other driver, when I tried to pry the ring from the headphones, the clay stuck the mesh material. When I pulled it away, the mesh material came off the headphone, so I had to put it back before I messed up my mod.
And here are the pics of the ring I was talking about. Now you should see how it works, right? I taped the earpads to the ring, and the ring sticks to the headphones by the clay. It doesn’t move around or anything, either. The clay actually makes a great seal, and you really have to pry it open in order to move it, especially after the clay has set in for a day or so. Don’t mine the electric tape on the underside of the ring. When I was modding the Pro700MKII way back when, I thought that by putting electric tape over the mesh would make them sound better…it didn’t do anything to the sound. Since it didn’t hurt to keep the tape on there, I just left it. Of course, some of you guys are wondering why I violated my pair of Pro700MKII's...I got curious. Behind the driver on the Pro700MKII, there was some felt material covering the holes (all but two completely open holes). I cut the felt material out, and I cut a hole in the headphones so that they could breathe correctly. That's the super condensed version of the story, but that's basically what happened. Afterwards, the driver broke (when I was resoldering the headphone cable, a solder ball went inside a hole I cut out and burnt a hole in the membrane), and I picked up my AD900s.
Here’s the headband. I had to unscrew the inside of the part where the wires go inside, take the wires out of the sockets that they were in (they have an L-shaped hook that hooks in on either side of the U shape you see on the last pic), get the vise grips, bend the left and right sides, and I used my hands to bend it in the middle. Getting those wires back in were a pain, too.
Here’s the way I rigged up the speaker outputs to my headphones. I need to get some better cable in the future, but this will suffice for now.
For any of you guys that have an AD2000, you'll see that the grill on mine is more convex than a standard AD2000 grill. I took the grill off the driver, and pushed it outwards. Whenever the bass played, especially at louder volumes, the membrane had a tendency of hitting the inside of the grill. Take a look at the my AD900->AD2000 driver transplant mod in my signature. It'll show you how I got the drivers in there, and how I bent the grill.
When I smashed the ring to the headphone frame, there was some clay that was wedged inside the driver area. I just smashed it around it to seal any gaps (don't mind that little piece hanging out, I mushed it in after taking the picture). If you have even the smallest gap in the clay, it will noticeably affect bass performance in a negative way. Don’t mind the electric tape covering the little screw holes. I was doing an A/B test to see if covering them would change the sound characteristics. It didn’t.
I didn't force them to be like that, either. That's just the way they rest now. The clamping force allows the headphones to take that position. Pretty neat, huh?
Conclusion (Click to show)
So, the conclusion. Well, I’ve already typed up enough stuff, so I guess you guys have a pretty good idea of how these headphones perform. If you’re one of the people who just skimmed through the review, then shame on you, lol. Here, I’ll make a TL; DR for ya:
They’re probably the best dynamic headphones ever made, especially if you’re a basshead.
You see I said dynamic, not just headphones period. I’ve heard some good things about some electrostats and orthos, and I’m not confident saying that I have the best headphones ever, especially in the light of something like the Stax SR-009. Plus the audiophile world is really subjective (don’t worry, I tried to make this review as objective as possible). One thing I am completely confident on, though, is that these are the bassiest headphones out there, partly thanks to the seemingly endless volume levels that the speaker-outputs the receiver grant me. My headphones without any bass boost may be outperformed by headphones like the xb500/700, or the V-Moda Crossfade LP purely in the bass quantity department, but it would be a disgrace comparing those headphones to mine. My headphones scoff at those sub-par sonic reproduction devices. I don’t think many headphones can take 20dB+ of bass boost and the power of a speaker amp and live to tell about it.
The best part of it all is that I probably invested around $300 in these headphones.
Well, that’s the end of my review of the AD2000MKIV. I hope you enjoyed the write-up, and feel free to reply about anything regarding them.
Moral of this review: Don’t be afraid to try something different. You may be heavily rewarded in the end. I’ve done a whole lot of modifications prior to ending up with these headphones. Some were good, some blew the drivers, and some were outright stupid (google images GBH-1000, and you’ll see what I mean…), but I’m glad I took the dive to try out something different instead of just buying multiple headphones. I guess now I’ll have to get some headphones in order to compare them to mine instead of getting headphones to replace them, compliment them, or just to have something different. I don’t think any headphone will replace them, since they’re really unique. Complimenting this headphone will be extremely hard since they sound good with everything. Classical? Covered. EDM? Covered. Jazz? Covered. Rap, Hip Hop, R&B, etc.? Covered. Anything else I haven’t covered? Covered.
Who will be able to dethrone them? Idk, but I’m broke, lol.
Edited by Trae - 12/29/13 at 8:35pm