[janderclander14]

Hi,

As a result of the interesting opamp rolling discussion of the ZERO dac/head amp, I would like to know which opamp do you think is the best suited for a DAC.

I mean, to be used as the output stage of a DAC and not for driving headphone directly. In my opinion, for this purpose, the opamp should be as transparent, neutral and less intrusive as possible (as much like a cable shortcut) in order to maintain the sound fidelity to the source.

In this case, its capabilities of driving high impedance headphones or introduce suitable colorations for one model cans or another are secundary (which will be considered in the headphone amp stage or an external headphone amp).

I am currently using the lm4562 as the dac output (soundcard). What do you think? Other opamp suggestions for this purpose?

Cheers

 

[Capunk]

My suggestions:
- 2 x OPA627
- 2 x OPA637
- LCT6421HV (Tubes opamp)
- NE5532 (don't kill me)

 

[majkel]

The LM4562 goes even further than being neutral, it makes music grey which I don't like. Neutral means preserving color and timbre without altering it.
If the op-amp is connected straight to the DAC output, you better use a FET input op-amp. I'd begin with the OPA2604, it's dedicated for the I/V stage and does it very well in my CD player. The OPA627 and OPA637 are almost neutral but they miss one point and that's why I don't like them - they lack PRAT, sound kind of slow, uninvolving, they never make me tap, or bob my head. And they are expensive. Actually it's difficult to find a neutral FET input op-amp. There is more of them with bipolar inputs but they will be suitable only when you have a voltage output DAC. If it's the case, and LM4562 played well, you can try:
2x AD8021 - the most neutral what you can get (chip dedicated for 16-bit ADC buffers, very fast)
AD8022 - it's not a dual version of the AD8021, has got high current output, very low noise and distortion, spatial and clear sound. I put it in my CDP as the output drive.
AD8599 - another low noise, low distortion dual op-amp, sounds a bit warm and "plushy", I'm using it in my CDP on the second stage filter/difference amp

 

[Don Juan]

With a 7.5 uA Ib and a 24V maximum power supply I don't know how likely it is that you could use the AD8021 successfully.

The LME49720 is a better choice than the LM4562 (even if specs are identical, it's reported to be smoother and more musical).

My other suggestions are the LT1122, LT1361, LT1364, LT1469.


The LT1361/4 is a wonderful dual opamp. Single versions LT1360/3. Check Audio Asylum for more info.

 

[janderclander14]

Thanks for your suggestions.

The DAC is an AKM AK4396 with voltage output so bilopar opamps work fine.

I am also curious about the differences reported between the lm4562 and the LME49720. Many users say their are identical but I had also found some opinions indicating than the later sound more musical. Does anybody actually compare them?

 

[Don Juan]

Sorry, unfortunately I have used them in different amps.

What I know is that I did find the LM4562 (used alone, with a discrete buffer) unmusical. Whereas the LM49720 coupled with an LT1364 (in a successive stage) has been sounding very good to my ears - I wonder how much of the merit goes to the LT1364.

 

[Joelc87]

I'd second that for the OPA 627, great transparent sound. Very low noise too.

 

[majkel]

After some tests I strongly recommend LT1364 as well, OPA6x7 make music lose pace and rhytm, it sounds dead.

 

[Gradofan2]

The 2 x OPA627s (require brown dog adapter) sound great in my CDP.

But... the OPA2134s (dual chanel) sound a bit better, I think - a bit faster, more detailed sound... but still warm, organic and weighty.

 

[jimmy8269]

X 2 for OPA2134

 

[majkel]

If the original op-amp ins't FET input, I wouldn't use a FET input one instead. They are "necessary evil" IMHO. If it's not the first stage after DAC, go bipolar. The most similar to the OPA627 bipolar op amp is OPA211 and it sounds better IMHO. My preferences look like this:
Bad FET dual: OPA2134, OPA2132
OK FET dual: AD8620, AD8066, OPA2107, AD746
Good FET dual: OPA2604
Bad bipolar dual: AD826, AD823, OPA2227
OK bipolar dual: OPA2228, LM6172, LM4562
Good bipolar dual: AD8022, AD8599, LT1364
Bad FET single: no idea or dual equivalent exists
OK FET single: OPA627, OPA637, AD744, AD797, OPA602
Good FET single: AD825
Bad bipolar single: no idea or dual equivalent exists
OK bipolar single: as above
Good bipolar single: OPA211, LT1028, AD8021

 

[Apocalypsee]

Quote:

Originally Posted by janderclander14 /img/forum/go_quote.gif Thanks for your suggestions. The DAC is an AKM AK4396 with voltage output so bilopar opamps work fine. I am also curious about the differences reported between the lm4562 and the LME49720. Many users say their are identical but I had also found some opinions indicating than the later sound more musical. Does anybody actually compare them?

I would suggest LM49720 if you're a detail freak, I never heard from LM4562 but from other's reviews, it sounds dry and sterile, but some people likes it though.

I use Prodigy HD2 soundcard which uses AK4396 DAC and it worked well with the LME49720. The stock NE5532 that come with the card doesn't sound that bad too, only losses on the vocal part, uncontrolled bass (boomy) and huge loss in detail

 

[afshin]

hi all
I m new user this form...
I have test some model opamp .I Think  2132 very better than 2134 !!!
and lme49720 is very good for I/v after dac  ... I used it for I/v after wolfson  192KHZ  64X (WM8716) ... sound very detail and smoot ...
I recently bought opa2604  and yet not I receive the invitation, and I'm waiting for a replacement test 2132.iI want use in filter amp ... Do you think this is good?
 
Thank .afshin

 

[afshin]

~~No one is here! I've tested opa2604  I've heard good sumptuous short, I love it a little rough ... Thank you.

 

[Dougct7]

My soundcard plays with two DAC OPAMP chips inbound in parallel and two analog(headphone, RCA) chips outbound in parallel.  What do you recommend to inbound and out bound?  They are both dual channel for all four chips.