Threadbare and grainy treble, a DAC issue?

Assuming everything else in your system is up to par, then yes your problem could be your older SS DAC and a new tubed based DAC might just be the ticket. Might. But the ability to experience grainy/overly bright highs could easly be sourced to other components,wiring, etc. Have you listened to a different DAC/Transport combo, or a CDP, in you system and pinned down your 'problem' to your Goldmund/MBL?

The short answer Chris is yes, it's the Goldmund DAC that is giving you the highend shortcomings you are describing. Its been years since I have listened to Goldmund CD gear, but what you are describing is what I remember as digital gear was improving over time.

The Wiess DAC offers what I call a type 1 sound and the Accustic Arts Tube hybrid offers more of what I refer to as a type 2 signature. If you go to my thread, Reference DACS: An oveall Perspective, you can get a ton of details regarding this subject. Also, I have written a review of the AA Tube Hybrid here on the GON, and still believe it's one of the best DACS out there, for alot less money compared to other world class reference level DACS.

I do not agree that the Goldmund is the cause of the grainy treble, as I have owned them personally, and found out that it was one of the softest sounding DAC's ever made.

Probably it is the power amp or the pre-amp