Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › AUNE Headphone amp + DAC Review
New Posts  All Forums:Forum Nav:

AUNE Headphone amp + DAC Review - Page 2

post #16 of 21
6/25/10 at 10:33am

My OPA627 chips arrived from Newark. I mounted them on a new adapter and tried them in the Aune's output position. Without any doubt, these are the best ones out of all the others I have tried. With some of my other opamps, I need to strain to listen for the differences in performance. Or switch back and forth repeatedly to make sure it's not just my imagination. But with the OPA627, the difference is very obvious. I would not go so far as to say these are better in every way to the LM4562 or AD744, but if I had to choose one it would definitely be OPA627.

 

I am presently using them in combination with the AD744 chips in the lpf position. I had to stack the adapter on an extra DIP socket to avoid bumping into the capacitor nearby. So I've got a total of 4 opamp chips in there now on 2 adapters. In theory this means better channel separation and soundstage.

 

sberamji, I'm curious if you tried using both the OPA627 and AD797 (I don't have the latter one) at the same time. (That is, use your 797 in place of the 2134.) My thinking is that it may combine the strengths of each chip. The best of Burr Brown and AD "house sounds". So you get both extension and resolution, plus fun and speed, all at the same time?

Reply

Gear mentioned in this thread:

beyerdynamic DT 880 Premium Headphones
post #17 of 21
6/25/10 at 12:33pm

don't forget to try LT1028AC and LT1363

Reply
post #18 of 21
6/25/10 at 12:34pm
Thread Starter 

Yes I did try the AD in the DAC section and the OPA627 in the amp section and yes you are correct. That combination did give me the best results. With the AUNE I cannot stress how imp it is to have dual opamps. This is the BIGGEST difference that I consider an upgrade. Changing opamps changes the character of the sound which depending on your tastes would fall into different cats. However changing to a dual opamp configuration makes everything more controlled. The muddiness goes away and for a change we get a slight soundstage as well instead of of wooly mushed up lumpy sound.

 

The Ad797 in the DAC position does help balanced out the 627's sound and does give a pretty decent complete sound. However no matter how much I tried to play with the DAC section of the AUNE I just cannot seem to get it to time like the Sim nor can I get to to sound as natural and free as the Sim either. Of course the Sim is a special CD player but I was hoping I could get a giant killer from the AUNE. It just lacks the timing and the naturalness of vocals that the Sim does. However compared to cheaper CD player the AUNE DAC with the AD797 or OPA 627s in the DAC stage can sound very very good.

 

WIth the 627s in the amp section and the 797s in the DAC stage I did notice that the AUNE will struggle at louder volumes. Of course my big Beyers would be the problem but I did notice that the AUNE looses control at louder levels, specially using all 4 opamps installed. I am currently trying the AUNE with LM5161 opamps (used in Meiers top of the line amp) and I think they have a sound a touch below the 627's. They dont have that buzz effect like the 627s do but they are very smooth, non fatiguing and free flowing. They however do lack detail and bass extension as well. They would do good with a headphone that is skewed in the highs and lows as they have a nice warm mid range that would fill it out. But once again using them as dual opamps the benefits are there! Everything is well controlled and separated! So to summarise the Aune - the 627's in the amp stage sound the best but if ou use a 600ohm headphone or an AKG 702 the AUNE will run out of steam. If you add the AD797 in the DAC section it mates very well with the 627's and everything balances out very well but make sure you are not using demanding headphones or the AUNE will run out of steam again!

 

I have a pair of AD797 opamps (no adapter) and a 18V 1.3A Elpac switched power supply (no power cable) for sale. Am looking at $35 shipped if anyone's interested for the set.

 

SB

Reply
post #19 of 21
6/25/10 at 7:41pm

I don't think it's "running out of steam". The opamp that is in the DAC section needs to be unity gain stable. I don't believe the AD797 are unity gain stable so they maybe oscillating causing the distortion you hear. The OPA627 is unity gain stable and should work well in the DAC section.


Edited by francisdemarte - 6/25/10 at 7:44pm
Reply
post #20 of 21
2/22/11 at 9:51pm

 

awww man i just bought a udac2 then i saw this one.... is the aune much better than udac2.....

 

but overall that dac looks really sexy

Reply
post #21 of 21
3/14/11 at 2:26am

 AUNE Mini USB DAC + Headphone Amp [Special Edition]

+

 burson regulator/ mundorf m-lytic for 18v power

burson clock/1ppm txco (for usb)

elna silmic recap

burson opamp

 

= happiness :)

 

 


Edited by gwillys - 4/2/11 at 5:16am
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)

Gear mentioned in this thread:

beyerdynamic DT 880 Premium Headphones
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › AUNE Headphone amp + DAC Review