[Kain96z]

 I'll start by saying that I'm a new audiophile so I'll apologize for being a little green to this. So here's my dilemma. I've recently purchased a pair of AKG Q701 and initially I was a little disappointed with there performance until a friend of mine (that knows a little more then I do about this stuff) realized that I wasn't properly powering them. So with some rewiring of my set up I know run everything through a Yamaha RX-V373 series head unit and the difference is night and day. I thought I was happy with this set up. It runs my surround setup  for movies/TV perfectly with my current speakers and my AKG's never sounded better....... until I had the pleasure of my friends ancient tube amp from the seventies and my god I never new music could be so full and rich. (I begged him to sell it but that wasn't happening) I'm hooked, I only want the best for my ears now.
 
 So now with my intro over I'm having a very hard time figuring out all the info and getting the answers I need. I'm looking for a tube amp/dac that can properly drive my AKG's. Everything I've read tells me these are a particularly difficult headphone to drive properly. I'm having difficulty with the lack of info I keep finding on the amps I look at. I'm looking for something in the $350ish range? I'd be willing to go a hire for the right amp. More then one optical port would be nice as well. I want to run this from my pc,xbox and head unit. I listen to some base heavy music but also a lot of blues, jazz, soul, and a lot of rock if that helps?
 
 I've gone through so many post about these headphone but I cant find anything that answers my specific questions. Theirs over 4000 post relating to these headphones. Its a little much to go through. 
 
 Any help is greatly appreciated. And just a little added question. Is there any good portable tube amp/dac that would be a good match for a pair of westone 4r's and my iPod?

 

[cel4145]

Audio-GD Compass 384 has optical, usb, coaxial, and analog line in. That should take care of all your devices since you can use the USB for your PC. Lots a love for Audio-GD on head-fi.

 

[tomb]

Well, that's fine if you want a solid-state amp with a DAC.  Problem is, that's not even close to what you've experienced.
 
The possibility is that if your friend had a truly old tube amp, most likely it was a true output-transformer-coupled tube amp.  A lot of "modern" tube amps available these days are "OTL" - Output Transformer-Less tube amplifiers.  That means the tubes, which are typically super-high on voltage and very-low on current, output directly through capacitor filtration.  The capacitors are needed because tubes are inherently biased with DC, which if exposed directly to the headphones, could burn them out.  Capacitors block the DC voltage, but it comes at a price: the capacitors color the sound signal and the output has very little current.*
 
In comes the AKG K/Q-701/2/12 and it's relatively low impedance (62 ohms) and high current requirements, and a typical OTL amp chokes on the load.  Solid state does nicely in this regime, but it lacks the soundstage optimization for which the K701's have been designed.  What you really need is a true, transformer-output-coupled tube amp.  My guess is that is what your friend has.  They're readily available, but you have to read the fine print.  For instance, Mapletree is a good example.
 
As for portables, I would recommend the Mini3.  Yes, it's solid-state, but it probably has more current capability relative to size than any portable available (You don't want to mess with tube portables, anyway - the only person I've known who was able to do it was Pete Millett and even he quit selling them (Millett Hybrid Portable)).
 
 
* There is another price with OTL amps, too - if the capacitors are not large enough, you will get bass-filtering with lower-impedance headphones.

 

[PurpleAngel]

   I'll start by saying that I'm a new audiophile so I'll apologize for being a little green to this. So here's my dilemma. I've recently purchased a pair of AKG Q701 and initially I was a little disappointed with there performance until a friend of mine (that knows a little more then I do about this stuff) realized that I wasn't properly powering them. So with some rewiring of my set up I know run everything through a Yamaha RX-V373 series head unit and the difference is night and day. I thought I was happy with this set up. It runs my surround setup  for movies/TV perfectly with my current speakers and my AKG's never sounded better....... until I had the pleasure of my friends ancient tube amp from the seventies and my god I never new music could be so full and rich. (I begged him to sell it but that wasn't happening) I'm hooked, I only want the best for my ears now.
So now with my intro over I'm having a very hard time figuring out all the info and getting the answers I need. I'm looking for a tube amp/dac that can properly drive my AKG's. Everything I've read tells me these are a particularly difficult headphone to drive properly. I'm having difficulty with the lack of info I keep finding on the amps I look at. I'm looking for something in the $350ish range? I'd be willing to go a hire for the right amp. More then one optical port would be nice as well. I want to run this from my pc,xbox and head unit. I listen to some base heavy music but also a lot of blues, jazz, soul, and a lot of rock if that helps?
I've gone through so many post about these headphone but I cant find anything that answers my specific questions. Theirs over 4000 post relating to these headphones. Its a little much to go through. 
 Any help is greatly appreciated. And just a little added question. Is there any good portable tube amp/dac that would be a good match for a pair of westone 4r's and my iPod?

Using HDMI from source to Yamaha might offer better audio quality, over S/PDIF (optical & coaxial), not sure how your currently connected.
With your iPod your better off just getting a good portable solid state headphone amplifier (Fiio E11, $63) and an LOD cable to connect the Apple's LOD port to the line in on the portable headphone amplifier. Or buy a better DAP (Digital Audio Player) then the iPod.
 
With a game console it's not really easy to have surround sound and a really nice DAC, headphone amplifier is not as much a problem.
What you might consider doing is upgrading the Yamaha receiver, from the RX-V373 to the RX-V671, Accessories 4 less is selling a refurb RX671 for $319, with free shipping, you can sell off the RX-V373 for some cash.
The RX-671 may not match the old 70s tube amplifier, but upgrading the Yamaha makes the whole headphone audio setup easier, plus your speakers will benefit from the RX-V671's better speaker amplifiers (over the RX-V373), and you get the cash from selling off the RX-V373.
 
http://www.accessories4less.com/make-a-store/item/YAMRXV671BL/YAMAHA-RX-V671-7.1-Channel-Network-AV-Receiver/1.html

 

[Kain96z]

I think you hit the nail on the head with what type of tube amp that was. We literally set a pair of Sony bookshelf speakers on fire because I didn't believe it could do it and oh boy it did. As far as what the amp actually is we both have no idea. All we know is that it was bought in England in the seventies by his father (who was an audiophile himself) and brought to the states when he relocated. The amp has spent over 20 years in storage and from what we can tell all the identifying markings have just rubbed away over time. It still sounds amazing after all those years.
 
Thank you tomb, I think you sent me in the direction I was looking for. So I'm the hunt for a transformer-output-coupled tube amp. I guess the only problem now is rethinking my price range and maybe a little reworking with my current set up. 
 
As far as my current set up goes to help clarify were I'm at,
My Yamaha gets optical from my pc (basic little 5.1 card) and my TV, coaxial from my DVD and the gaming is a little weird but it works. I have optical from my Xbox to an Astro mix amp which I then run a 3.5mm cable from the headphone out line to the stereo input in the back of my Yamaha. I know it kinda defeats the purpose of an astro but I still get there sound presets which helps with situation awareness in my fps games. The mix amp just can't power my Q701s at all. I'm honestly looking into a less power hungry headphone for just gaming now. I've read good things about the ATH-AD series and astros being a good combo for fps gaming but that's another discussion for another time. And I do have a good set of Sony 5.1 speakers with a powered sub for movie night.
 
This set up works well for me until I want to listen to music with my Q701s. I just know I'm missing that brilliant tube amp sound to take my music to that next level. And thanks for the advice on the portable amp for my 4r's. I'm just going to keep it simple with a solid state for now.
 
And I always thought optical was better quality then coaxial and HDMI for audio.....? AM I just misinformed?

 

[PurpleAngel]

  And I always thought optical was better quality then coaxial and HDMI for audio.....? AM I just misinformed?

For anything more then 2 channels of audio, like 6-channel (5.1) or 8-channel (7.1) HDMI is better.
Try running HDMI from your computer's graphics card and the PS3 to the Yamaha, see if you can notice a difference.

 

[Kain96z]

  For anything more then 2 channels of audio, like 6-channel (5.1) or 8-channel (7.1) HDMI is better.
Try running HDMI from your computer's graphics card and the PS3 to the Yamaha, see if you can notice a difference.

I will defiantly try this out tonight. ****, this means if it works I'm going to have to color optimize my TV again lol. Thanks.