A comparison between two DACs, one R-2R, the other ES 9038-based.


This is an item from the FWIW Department, I guess.

Recently I set up an A/B comparison between a Denafrips Pontus and an OPPO Sonica…. Both DACs fed from a Nuprime CDT-8, via the XLR inputs on the same preamp, and everything else constant through the two signal paths to the speakers.

The result when I repeatedly toggled back and forth from the preamp’s input one [Denafrips] to its input two [OPPO]?---- To my surprise [and disappointment], the sounds from the two DACs were utterly indistinguishable, across all kinds of music, after repeated trials … impossible to tell apart… impossible.

The moral of the story? I don’t really know, but it does suggest to me that those who say that DACs of comparable quality cannot be told apart just might have a point.

I bought both the Pontus and the Sonica because I thought that it would be nice to have on hand DACs of “different flavours,” one based on an R-2R ladder, the other based on a delta-sigma chip. 

I did want the expected difference to be real… just for the fun of it… else why spend the extra money? So, my “confirmation bias” was, if anything, stacked in favour of there being a detectable difference.  

However, the results of a reasonably well controlled comparison [sadly?] did not bear out that expectation. Differently based DACs, 2-R2 vs delta-sigma, may not offer such different flavours as many suggest. Is that claim all much ado about nothing?

Thoughts from members of the Forum?

 

 

 


128x128Ag insider logo xs@2xzimmerma
Hi simna... .I did not take you to be a smart arse.... Not at all.
I just do not know the two DACs you mention, except to note that the LAB12 has a tube in the output section and the Hegel does not, so maybe that makes for the noticeable difference you hear.
Single most important factor when testing is the volume. Needs to be within +/- 0.2 db. Sometimes a problem with stepped volume controls.


To jaybe again....

No offence taken re your comments on my PS Audio PCA-2 preamp [though I think that Paul Gowan really would bristle at the "mid-fi".... and I note that the other preamp employed, the Wyred4Sound STP SE, is a current design], nor on my Anthem MCA 20 amps.

 .... And I do not really want to get into a tussle [here, anyway] about whether there are dramatic differences amongst preamps and amps....

I thought that the point of an A/B comparison of DACs would be to keep everything else in the signal path constant, as long as a decent level of electronic quality was maintained, not necessarily to use the latest and most expensive preamps and amps. 

The questions to you are, I guess, these:
  • In order to get a realistic and accurate comparison between DACs does one really need to use the the latest and most expensive preamps and amps?
  • Would that be the only way to reveal audible differences between DACs?
Thanks for your comments.   
To gosta:

You are so right about the importance of maintaining the same volume control across the comparison---
This is pretty easy to do by... 
  • keeping XLR/XLR and RCA/RCA input switching constant from the preamp during the A/B comparison, and 
  • leaving the volume control set at one point, and just switching from one DAC input to the other. [Actually, I had my wife do it, to retain that "double-blind" aspect of the tests.] 
Thanks, gosta, for making the point about volume control explicit. I should have mentioned it in the OP?
@zimmerma .. I’ve not heard your DACs in particular but I can hear distinct differences between the 4 I have, which includes both R2R multibit and delta/sigma types. (There is a small part of me that wishes I didn’t hear said differences to be honest.) I’ve found the A/B quick-switch method doesn’t reveal DAC nuances nearly as well as a lengthier listen. For me, a relaxed non-focused listen allows me to hear the subtle differences and, once heard, I can never un-hear them. Said differences are then not so subtle. DACs, as you put it in your op, offer differing flavors. I have 4 DACs because I enjoy change.