[Shazb0t]

What follows doesn't apply to the Q701 but to the HD650 and will vary depending on what dac used: 

The O2 can be funny w/ some dacs because of the impedance of the ODAC. I had bass distortion w/ the HD650. I contacted John at JDS labs and wrote the following: " On high gain, the O2 is breaking up with my HD650. The bass gets crackly and distorted, especially around 60hz at -10 db. Other frequencies give it trouble on some songs too. I had to wait to get another amp to see if its definitely not my DAC and not my headphones. Is this just the O2 being maxed out or is there an issue with it? With another amp, the system does not have that problem..." John was helpful and responded: "
This occurs with O2 when using a strong source/DAC with some headphones. You simply need a higher voltage AC adapter to use high gain. More information can be found on the instructions guide." And here is a link to the PDF: 
http://www.jdslabs.com/pdf/Instructions_O2.pdf
 (Search for distortion) 


In other news, the Magni would have to be the clone of the O2, since the O2 came first! But don't worry...it's not! 

High gain on the standard o2 is for use with portable sources that don't have high output. If you want to use the o2 with a standard output DAC then you should clip the resistor on your o2 giving you unity and medium gain option.

 

[Advil]

I hear these are pretty cold sometimes. Would a Tube amp warm them up a bit? I have a Little Dot II++ and really, really want these headphones.
 
I also have an E17 and pa2v2. but they're pretty neutral I think.

 

[tdockweiler]

Quote:

I hear these are pretty cold sometimes. Would a Tube amp warm them up a bit? I have a Little Dot II++ and really, really want these headphones.
 
I also have an E17 and pa2v2. but they're pretty neutral I think.

Not even remotely cold IMO. Maybe you read that about the K702?
E17 is pretty good as a DAC for them since it has many a small touch of warmth.

 

[Ashade]

Ummmm....
 
I recently got these in a head-fier transaction and... WWWWOOOOOOWWWW!!!
 
I am amping them with Fiio E07K but I am guessing is not enough. Would the E09K addition suffice? Sorry if this has already been asked, new to the thread.

 

[theOmni]

can anyone comment on these headphones and the dt990? I'm looking for more perspectives and opinions in terms of gaming.

 

[imackler]

Quote:

can anyone comment on these headphones and the dt990? I'm looking for more perspectives and opinions in terms of gaming.

I don't game but if you haven't seen it, this guide may be useful: http://www.head-fi.org/t/534479/mad-lust-envys-headphone-gaming-guide-updated-8-17-2013-cal-nuforce-hp-800-fiio-e12-reviewed

 

[jimmers]

Quote:

 
 John was helpful and responded: "This occurs with O2 when using a strong source/DAC with some headphones. You simply need a higher voltage AC adapter to use high gain. More information can be found on the instructions guide."

That's kind of disappointing from a supplier, if the AC supply is sufficient to avoid drop out of the 12V regs no more voltage is going to help. From a red book DAC (2V rms max output) a standard low gain of 2.5 (on my O2) is about as high as you can go on fresh batteries (that's 5V rms, 7V peak, so less gain would be safer - designer recommends 2.25 max) and you wouldn't want to go much higher even with AC adaptor (designer recommends 3.5 max). The thing to remember is that the O2 overloads in the first (gain) section, the position of the O2 volume control has no effect on this.The high gain you would pick to suit your low level analog input.

 

[Chris J]

That's kind of disappointing from a supplier, if the AC supply is sufficient to avoid drop out of the 12V regs no more voltage is going to help. From a red book DAC (2V rms max output) a standard low gain of 2.5 (on my O2) is about as high as you can go on fresh batteries (that's 5V rms, 7V peak, so less gain would be safer - designer recommends 2.25 max) and you wouldn't want to go much higher even with AC adaptor (designer recommends 3.5 max). The thing to remember is that the O2 overloads in the first (gain) section, the position of the O2 volume control has no effect on this.The high gain you would pick to suit your low level analog input.

 
Looks like you've found a design flaw..............

 

[Evshrug]

Totally agree with this. Fuller mids and for me way less fatiguing treble. Based on memory the soundstage of the AD700 might be a bit larger. The mids on the AD700 seem a bit lean, sort of like the old K702.
One headphone I liked more than the AD700 was the AD300. Sounds a lot different but almost nobody has heard it!

Still need to hear the A900X and AD900. I loved the ATH-AD2000 but it's pads are awful!! Who designs a $400+ headphone with pads that go flat and your ears press against the driver?

Yeah, to be honest, I didn't even "need" more bass, but I went to the Q701 for the fuller mids, and that "wow!" factor. I directly compared the AD700 to the Q701 over the course of 5-6 months or so, the AD700 didn't have a BIGGER soundstage IMO, but what was apparent, especially while gaming and using headphone surround processing, was that the AD700 had a more evenly round soundstage, while the Q701 has a more oval wide-ish soundstage, unless the Q701 is amped well. I tried a few tubes before I found one that accentuates the soundstage to be basically as even as the AD700, so I'm happy in pretty much all ways now, but it was easier to get the AD700 amped to create realistic soundstage. I did like the wings and lightness of the Audio Technicas, the pads didn't bother me once I got them angled right (Dunno who was the design model for the non-adjustable pad angle... Stewie Griffin?), I would also like to try the higher-end Audio Technicas, but I really don't have a need to do so.

Thanks for reading my post. I asked a while back about cables, I think I found a nice short one on eBay, maybe I'll put it to the test next payday, thanks for your tips. I'm curious to hear updates on your listening experience with the O2.

 

[theOmni]

Is there any difference between the Fiio E7 and the newer Fiio E07k? I can get a used E7 for $30 from a friend vs a new E07K for $90. I'd much rather spend just the $30 if I can. It will mainly be sitting on my desk and driving these headphones from my laptop. 

 

[Brooko]

Quote:

Is there any difference between the Fiio E7 and the newer Fiio E07k? I can get a used E7 for $30 from a friend vs a new E07K for $90. I'd much rather spend just the $30 if I can. It will mainly be sitting on my desk and driving these headphones from my laptop. 

 
They are quite vastly different - especially in power output and software implementation.
 

• E7
  Output power = 150 mW into 16ohm, 16mW into 300ohm
  DAC section is Wolfson WM8740 - USB implementation has limit of 16/48.
  3 stage bass boost
  I personally found the E7 a little cold and thin when I had it.
   
• E07K
  Output power = 250 mW into 16ohm, 36mW into 300ohm
  DAC section is also Wolfson WM8740 - but USB implementation has limit of 24/96.
  Steppable tone controls for bass and treble
  Most people suggest the E07K has a warmer tone

 
There are a lot of other differences you can find by simply googling.
 
Bottom line - if you were driving the Q701 - then get the E07K.  The AKGs generally like more power.

 

[theOmni]

is there any other option you'd recommend that isn't too expensive?
also, would an amp alone make these headphones sound good without a dac? I'm not too concerned about portability.

 

[Enverex]

I bought my Q701's a year or so ago to replace my rather aged Senn 580 HD Precisions (over 10 years old now) and considering the difference in price as well as the age, I expected the Q701's to be much better, but I must be missing something because the Q701's just don't sound anywhere near as open and immersive - the sound just feels restrained and compressed.
 
I bought an Audio-gd 10.2 and that helped a bit, but still it feels condensed and my 580's still seem more spacial and overall filled out. My second gripe would be that they seem to clamp pretty hard which in turn makes the sides of my head hurt after even slightly prolonged use (although the bumps on the headband haven't bothered me - which is what people normally complain about).
 
Am I missing something here in terms of the quality and the sound?

 

[ethan7000]

Age doesn't matter - the 580's are just awesome in any time period

 

[kenshinhimura]

Quote:

is there any other option you'd recommend that isn't too expensive?
also, would an amp alone make these headphones sound good without a dac? I'm not too concerned about portability.

the e07k is fine for an inexpensive dac/amp. used it with my q701 back when i still had those headphones.