I'm no expert, but I've read in multiple places on these forums that the ad700 is relatively easy to drive and delivers satisfactory sound even from an unamped source, while the AKG k700 headphones are VERY hard to drive and sound very weak and thin without proper amping.  Did the OP mention their source?  I would think another Audio Technica would make sense since they're typically easier to drive (in case their primary use is on an iPod or Zune or something)?

 
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junliang said:

Hmm, if you like the ad700, you can give the k701 a try
 
I use k701 for my music, then gotten the ad700 for my gaming and found much similarities between them but with improvement at the k701 side.
 

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Quote:

arkaium said:

I'm no expert, but I've read in multiple places on these forums that the ad700 is relatively easy to drive and delivers satisfactory sound even from an unamped source, while the AKG k700 headphones are VERY hard to drive and sound very weak and thin without proper amping.  Did the OP mention their source?  I would think another Audio Technica would make sense since they're typically easier to drive (in case their primary use is on an iPod or Zune or something)?

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Yes, the K70x headphones from AKG will do nothing for you if you do not have a proper amp.  My friend and I tested this ourself. . .they will be extremely quiet and lack a vast majority of their bass.  Once they are properly amped though, the bass really comes round and can be "alright".  I suppose w/o an amp the K70x's bass is vastly lacking. . .exactly like the AD700's. . .main concern for the OP I guess would be the complete lack of volume from the same non-amped source.
 
Also, I would recommend the 600 ohm versions of the DT990's as opposed to the 250 ohm.  Almost every single person I have seen that has had both, greatly prefers the 600 ohm version (quick ex. http://www.head-fi.org/forum/thread/500446/deal-on-dt990-600-ohm/15#post_6770441).  I just got these (600 ohm version DT990) earlier this week and am driving them "ok" from my HT Omega sound card. . .they do need an amp however (future purchase. . .sigh).  The bass on the DT990's will also completely blow away the AD700's bass (or rather the lack thereof).

I bought a custom Mister X amp off off Head-Fi a few years ago and it was driving my AD700s.
 
I wonder if its enough to drive the 600ohm DT990s.
 
I am too, now torn between the 250 and 600.. unsure of which to get. 

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the_red said:

I bought a custom Mister X amp off off Head-Fi a few years ago and it was driving my AD700s.
 
I wonder if its enough to drive the 600ohm DT990s.
 
I am too, now torn between the 250 and 600.. unsure of which to get. 

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What are the output ratings for the various ohms on that amp?  Should have it listed in the literature somewhere (tech specs).

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ze_blitzkrieg said:

What are the output ratings for the various ohms on that amp?  Should have it listed in the literature somewhere (tech specs).

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It is custom, from MisterX.  He might have provided some lit with it when I got it, but as it was my first amp with a first high end (for me at the time) can, I was too disillusioned to remember where I put the manual now.
 
I have a solid feeling that they wont drive the 600s, no matter what I'm reading.  The AD700s they were driving previously were 32 ohms only.
 
So the ultimate question becomes.. will they drive the 250 version?

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the_red said:

It is custom, from MisterX.  He might have provided some lit with it when I got it, but as it was my first amp with a first high end (for me at the time) can, I was too disillusioned to remember where I put the manual now.
 
I have a solid feeling that they wont drive the 600s, no matter what I'm reading.  The AD700s they were driving previously were 32 ohms only.
 
So the ultimate question becomes.. will they drive the 250 version?

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Someone else would have to help ya there. . .no information for the various impedances doesn't help.  The DT990's in the 600 ohm version are not that hard to drive.  I think (correct me if I'm wrong) the max is only 100 mW in the 600 ohm version.

After searching the FS parts of these forums for a couple days now, I have decided to purchase the retail Bayer DT990 Premium (250ohm). 
 
Almost everything I've read about them makes them sound like something I should not miss.
 
We'll give these a shot, they'll be here on wed, I'll tell you how it goes
 
 
Thank you all for your input.
 
 
PS:

I now have a:  WTB: Driver for Audio Technica ATH-AD700s. (Or a pair of your broken ones)  thread in your FS/WTB section, I want to make a learning project out of fixing this pair.  If any of you can help me, I'd welcome it