Diablo 300 DAC Module - upgrade DAC or Streamer?

I’ve heard people complain about how Gryphon use “cheap” hard plastic feet for their amps. But my experience above makes me think this is very intentional.

Gryphon sells coupling spikes for their gear (stupidly expensive of course) but they clearly state they won’t help when used on their heavier gear like amps.

Still can’t get over how much of a negative impact the vibration control made with the amp. It was a massive change that anyone could hear. I think when I added the vibration control to the amp it was late at night and I didn’t immediately check for any difference in sound after installing. After all, I had previously installed Herbie’s Tenderfoots under the rest of my components with great success in improving sound, so I expected no less when using them on my amp.  And while it obviously caused issues for a few months I chalked it up to me having become more intimately familiar with my system including weaknesses.

Later I’m going to try adding only the Herbie’s feet under my amp’s feet, to see if they are the culprit or if it was adding the Butcher’s Block as well that caused the issue.

I have my Diablo 300 sitting on an Adona rack with it's granite surfaced multi layer shelving for a very solid foundation.  I considered other footer and isolation options but none I have borrowed seemed to provide any improvement at this point, though I'm sure there are other possibilities.  I find the Diablo DAC module works well with a quality server (which you have) and in my case the USB cable employed between them (I have spent time with 5 different ones since purchasing the Diablo 300).  I use Critical Mass Systems Rize footers under my DSA Phono 2 and My Wolf Audio Server.  I have considered the Critical Mass Systems Center Stage  2 as an option but they are a significant investment.

@drrsutliff thanks for your input. Currently I guess my observation is that adding vibration control, at least the type I used, was hugely detrimental to the sound of my amp. Which seems to possibly imply that the sturdiness and solidity of the foundation it sits on matters more.

I do have a heavy wood shelf that all of my gear sits on, but given the Diablo’s apparent sensitivity to the foundation it sits on, I’m wondering whether it’s possible to optimize this even more.

After removing the vibration control the sound has become much more solid, fuller and with more drive, energy, and far more bass response, with better soundstage depth and a more coherent and natural easeful presentation. Truly transformative.

Update:  currently I have 4 of Herbie's "Giant Fat Dots" between my wooden shelf my gear sits on and my wood floor.  I am now wondering based on my experience if instead of vibration control padding under my shelf, my amp would prefer it if I installed coupling spikes under my rack.  That said, I did notice a net gain in sound quality when I installed the 4 pads under my shelf.  But that may be due to the benefit to my other components.  Definitely warrants further experimentation I think, and this time I'll be more careful to gauge the impact of EVERY tweak.

These changes are all additive.  The combination of “under the shelf” plus “under the footers” may have been too much of a good thing.  Just one of those alone may be better than none at all.  If you are now at a place where the system is sounding  good relax for a while and enjoy.  Really take some time appreciate how it currently sounds before making any additional changes so that you have a new baseline to evaluate those changes.  Enjoy the holiday!