[RAZRr1275]

So I own the AKG K702, Denon D2000 and Grado SR80i. I have a budget of 400-500 dollars for an amp and dac. My files are mostly 320 kpbs or flac. I have a couple of questions.
 
1) For this price range do I get the best performance out of my phones from a tube or solid state? I am willing to do things like tube rolling etc as long as it all fits into budget
 
2) Which amps would you recommend in either categories and what do they sound like?

 

[hodgjy]

Those headphones you listed will not be optimally paired with an OTL tube amp.  If you want to go the tube route, you'll want a hybrid amp (which can be on the cheap side) or a transformer-coupled tube amp (which are not often very cheap).  I'd suggest you go the solid state route--it's the best bang for your buck for low impedance headphones such as the ones you have.

 

[LugBug1]

M stage and V dac.
 
The only hard to drive headphone you have is the K702's and the M stage is a good match for it. It also has gain settings to match the Grado's and Den's. (low gain)
 
The V dac is still probably the best budget dac on the market, you can pick up the original mark 1 quite cheap now.

 

[jackwess]

X2 on the Mstage, and the Hrt streamer dac. 
I've found that the M stage Dac version quality is not very good, thats why i recommend getting a separate. 

 

[hodgjy]

I mentioned this in a PM, but I thought I'd share it here as well.
 
Nice hybrids:
 
Hifiman EF2 ($169)
Bellario HA540 ($299)
 
Nice DACs:
 
ODAC ($149)
V-DAC II ($349)

 

[PurpleAngel]

Quote:

So I own the AKG K702, Denon D2000 and Grado SR80i. I have a budget of 400-500 dollars for an amp and dac. My files are mostly 320 kpbs or flac. I have a couple of questions.
 
1) For this price range do I get the best performance out of my phones from a tube or solid state? I am willing to do things like tube rolling etc as long as it all fits into budget
 
2) Which amps would you recommend in either categories and what do they sound like?

Might help to know what source(s) you plugging into?
The Little Dot 1 + Hybrid ($155) might work, designed for low Ohm headphones.
 
DAC might depend on your source(s)