Would you mind telling me about the 'dampening' mod you did for your Asgard? What is it intended to improve, and how has it helped?
The dampening mod is using the best vibration material I know of for audio which is f.o.Q T-102 (and T-32 for applications like cables or curved surfaces) inside the gear. This dampening material is hands down without question, the best bang for the buck tweak or mod to enhance audio reproduction for any piece of gear in an audio chain I have tried in over 25 years in this hobby.
DISCLAIMER: I do not work for, sell or have any financial interest in f.o.Q company or their products, I just use their products. The information provided below is for educational purposes. If you decide to try what I describe below I am not responsible for anything you do to yourself or your gear.
I mod or tweak all my audio gear, this was the first dedicated headphone setup I have ever really put together. My main setup downstairs is comprised of Proceed, Lexicon and Mark Levinson gear, which all have gotten the treatment I am about to describe. My Modius and Asgard 3 right now is packed up because I am selling my home, but I did take a pic of the inside of the Modius and what I did with the f.o.Q T-102 material. I applied the same treatment to the Asgard 3. As an aside, the f.o.Q material was originally designed to be used in Japanese aerospace industry and was tweaked for audio use. A package of the T-102 costs about $60, which I now purchase through eBay. I have also recently been told by someone I have shown the different uses within an audio system that f.o.Q T-102 and T-32 can be purchased from amazon.co.jp. The T-102 is a 2mm thick piece of dampening material with an adhesive backing. Inside a package there is enough to treat an entire headphone system, including headphones.
WHAT I DID: In the picture you see a single small, about 3/16" diameter piece of the T-102 on top of each cap. On the PC board where there are no conductive traces I placed pieces to dampen the board. Eventually I also placed pieces on areas of the chassis that I found to ring and near connectors. On the Asgard 3 I also used the T-102 on the Alps volume pot and IEC connector. In the Asgard I was lazy and just used scissors to cut approx. 1/4" squares and placed them on top of the caps vs punching small circles like in the picture with a leather punch.
WHAT IS IT INTENDED TO DO: remove vibration
HOW HAS IT HELPED: On each piece of gear, which is Modius and Asgard 3 for this discussion you will audibly hear the lowering of the noise floor. Like veils have been removed so more can be heard and felt into the music. To me easily 2-3 layers of noise floor for "each" piece of gear. I started with the Modius because it is so easy to open up. After treating the Modius with the T-102 dampening material I got a slightly wider and deeper sound stage, a bit more organic presentation (more like a ladder DAC then chip based), more micro and macro detail across the frequency spectrum, more nuance to all sounds. After treating the Asgard 3 I got the same results, now the combo has IMHO better PRAT. This will seem far fetched but after each piece of gear was treated it was obviously sonically superior then before treatment. The change is by a large enough margin that it would pass a blind A/B test. In another words treating each piece of gear is like getting a upgraded version.
There are a lot of uses or places within an audio system that T-102 or T-32 can be applied to improve sonics. Each application depending where applied will very from wow to that is an improvement kind of response. But it is all accumulative. Before I tried the f.o.Q products mentioned above in an inexpensive (or modestly priced) system, I thought the T-102 and T-32 will only be effective with more resolving gear, I have been proved wrong. Now the Modius and Asgard 3 combo sonically to me sounds much more refined then the $470 I paid for them (including tax and shipping), by a large margin actually.
Also important to mention, if you do try what I explained above use a Q-Tip and rubbing alcohol to clean the surface before applying the T-102 dampening tape. The tape takes about 5 days to fully cure but you will hear the majority of the sonic benefits immediately. If you like to tinker or want to upgrade the gear in your system, you should try what I described above. If you do, please post your experience so that others can benefit. Peace