Best practices when conducting a DAC comparison

GeorgeHIFI is so right about volume ,many would choose any higher level even the tiniest amount over the other component ,

.Someone mentioned MQA and why would anyone not choose a dac that didn’t feature this ?  Recording engineer and owner of AIX Records Mark Waldrep including others in the industry have plenty to say about MQA overthe past couple years , RealHD-.com is a great place to start ,

David 10 , have fun with your evaluation,.

First, thanks for the additional thoughts shared via the previous few posts.

Second, I will try to consolidate everyone’s suggestions on approach and put together a summary.

Third, the Denafrips Terminator is broken in and is performing very well. I’ll be swapping in the Schiit Yggdrasil to get some listening time with it (and the new Gen 5 USB board).

Fourth, a major UPDATE:

I thought I’d conduct the comparison over the Thanksgiving Holiday...but other priorities got in the way. I wish I had, because I now have a new element in the system. I’ve been waiting for a speaker delivery, which was planned and scheduled for before the Denafrips DAC was delivered. The speaker was delivered yesterday.

My original plan was to have the new speaker fully broken in as well as to have a significant amount of personal listening time with it. Since I plan to keep the new speaker (and the DAC that performs / has the best synergy with it) I think the best approach is conduct the DAC comparison once the speaker is broken in and I’m familiar with the new speaker.

Thoughts in agreement or contrary to this? If otherwise, I’m interested in how you would proceed? Thanks.

David,
I have now owned and auditioned a Bryston BDA-3, Luxman DA-06, and the Oppo 105d with its internal DAC.  Each, as you know, uses a different DAC chip: respectively AKM, Sabre Burr- Brown.
I now use exclusively the Bryston, sourced via USB by a Bryston BDP-3 streamer, or the Oppo disc player via HDMI.
The characteristics of these DAC's has been described by others, and there may be general agreement that the Luxman is 'very smooth', the Oppo (sabre) detailed but harsh, the Bryston in-between.
My personal impressions:
1. The Luxman employed for chamber music...string quartets, piano trios and quartets...
is 'muddy'....the lack of detail increasingly becomes annoying.  Its employ for solo piano invites similar comment.  Try as I might to persuade myself that the 'more expensive sound'...ie, the Luxman's...should be better than the Oppo's, I had to throw in the towel and
avoid the Luxman for strings and piano.
2. The Luxman employed for voice is a delight.  I've read of various hi-fi components
that a 'smoother' high frequency response decreases listener fatigue.
Such comment applies to the Luxman used, for instance, for listening to an
opera DVD.
3. That virtue is such that even 'downrated' DVD audio sourced to the Luxman via the Oppo's coaxial audio output was superior to the Oppo's internal audio decoding of opera DVD's,
including blu-ray DVD's.
4. The Bryston BDA-3 is a good compromise...' 
I struggled to parse the foregoing impressions in respect of digital source format...standard CD, SACD, hi res PCM, double speed SACD.   The sound quality seems to improve as one progresses from the beginning to the end of that list, but the DAC comparisons...at least my ear...are the same. 

A most excellent list, Steve.

The question that bugs me is that of optimizing each component for best results. Should David use a reclocker for both pieces in the comparison even if one benefits and the other doesn’t (assumedly because the latter has better addressed the issue of noise and jitter reduction internally)? Does that fairly represent the potential user experience of each? What about different cabling/power cords that optimize each independently?

The purists’ "apples to apples" mentality would seem to require that the exact same cabling (even using the included power cords and perhaps generic digital cabling) with no external devices in play. Sounds fair, but what if one component would benefit tremendously from a reclocker or specific cabling to the point that it significantly outperforms the other and/or changes David’s preference? Even worse if one is much less costly than the other and investing a relatively small amount (i.e. that the total investment would be significantly less) would make it equal or even to outperform the much more expensive competitor.

The Terminator lists for ~$4400 and the Yggsrasil for $2400. Would spending less than $2k to optimize the Yggdrasil with a reclocker, cabling, etc. yield a better sonic result, thus making it a better purchase decision for the same or lower investment?

Seems that in the "bang for the buck" approach that the answer would be to address this with a "same or less total cash outlay" comparison as this is the real world dilemma for many of us. But then there are those that will choose to use each without any "supplements" (reclockers or upscale cabling, etc) that would find value only from the "apples to apples" comparison. And also those seeking an "all out assault" that may have interest in an ultimate sound quality comparison with each having every enhancement specifically optimized for that particular component regardless of cost. Who, short of the most diehard professional reviewer, has a sufficient number of these ancillary components available to even begin to satisfy all possible curiosity?

David has a real challenge on his hands trying to potentially satisfy each category of reader. I wish him the best of luck.

Dave