"DCS Delius" DAC direct to Amp?

Your system seems pretty sophisticated.

Sorry I didn't really answer your question I see now you are looking for a direct comparison between on board and external preamplifiers. The point I was trying to make is that I have found the rabbit hole to go pretty deep as far as the Delius' direct to amp performance goes. It replaced a Threshold T2 preamplifier that was priced at around $6k when it was new circa 1993. It was easily as good but I didn't start to really love the sound until I made several upgrades. Delius sounded worse when I used the Threshold as the preamplifier and my dealer advised not to use it that way.

I always figured it had at least the equivalent of a $5-6k preamplifier on board, but there seems to be no limit to how well it performs as I improve the power conditioning and source. After upgrading to even better Transparent Power cords and especially after upgrading the Squeezebox's power supply, it no longer had what I thought was a sound that was a bit analytical and a little hard on the ears. It is much fatter and smoother sounding now. Those PS Audio Noise Harvesters took quite a bit of edge off the sound recently. This is with B&W N802 speakers.

I am curious, in what way did you find the system better with the Krell?

Blackstone, I felt the entire range tightened up a bit with the Krell versus direct. I found that the sound stage expanded with the Krell vs. direct, and with that there was more air/space in the sound stage and better focus of the individual components in the sound stage.

But and this is a big but, when I put the Krell back into the system (after taking it out for the direct running from the DCS), I also made adjustment to the speaker locations. With my Wilson speakers this can be quite noticeable. This is why I want to test the direct connection again to confirm the case as whether the direct vs. Krell was really an improvement or just the result of speaker placement.

The Krell actually has a pretty good (actually better than just pretty good) preamp section. It is based on the Krell KCT preamp (but does not include the cast connections). Obviously when I use the Krell HTS 7.1 as a 2-channel preamp, it is a direct/clean signal path (balanced in/out and no processing by the HTS). I suspect the Krell (HTS 7.1) could be bested by several other preamps I am considering (ARC, Aesthetix, BAT, Rowland, etc. . .), but not by a tremendous amount.

I am interested in your comments on the CI Power supply for the Duet and am going to look into getting one. I just had new dedicated lines installed 2 weeks ago and it definately took a little bit of time for them to burn in (about 50 hours) for the sound to settle down. I was surprised at the marked difference between the virgin new power lines and the same lines after running my system for 24 hours straight (obviously not listening the whole time). Initially I felt the new lines significantly reduced my sound quality (not just a little bit). Now, the sound is significantly better than prior to the install. I am talking major difference, nothing subtle at all - like listening to an old receiver with bad speakers to listening now to a good system - that different.

I am interested into which way you went.
I have used a Duet and just changed SB Touch. The Welborne power supply made quite a difference to the Duet and in your system I'd say the difference would be far greater.
I'm running a Camelot Uther directly into a Gryphon amp and am considering changing to a Delius, though I would not be able to audition. Do you by any chance know the Uther DAC?
Best regards
André