I am definitely going to be using 70 duro sorbothane from now on instead of the softer 30-40 duro I have used to date. I finished several days of listening to the Stax STXII pro alternating between the metal cover damped with 40 duro pieces or 70 duro and the 70 was clearly better. As soon as I tried them out the soundstage was wider, the bass cleaner and the separation of instruments as well as dynamics even more pronounced. Several people here had kind of figured out that smaller pieces were more effective than large, but the use of denser sorb is a new finding. We have discussed the issue of the duro of sorb a bit in this forum and I assumed that the softer lower duro material would absorb vibrations better than harder material. However some months back I spoke with a technical rep for Sorbothane who told me that the higher duro might be better because it was heavier and more dense. It seems he was right. I have a few more varieties to listen to and it now appear blutak needs to be considered too. I should be able to stick pieces of it on the SRXIII just like sorbothane.. . Quote: I agree with this comment and that of Sc0ttstax, above that we are looking at improvements in sound of the sort that audiophiles will pay thousands for. As much as anything done with the various Stax and ortho phones discussed here I recall some months how placing 2 little bits of sorb on an otherwise crappy set of earbuds suddenly brought them into the high-fi category. This makes me hope that we can yet do even better when starting with higher quality phones. II expect that after I get more information from these comparison studies that I will go back to my various Stax phones and apply what has been learned. And the improvements we are seeing cannot be obtained just by throwing money at the rest of the system since damping distortion will remain in the phones unless treated somehow. It seems as if few in this forum are ready to look into this problem. The need to damp mechanical vibrations in audio is not discussed very much. There is some discussion of speakers, and sorb has been sold as footer for many years for speakers and equipment, but I have never had the kind of success with footers that I am getting with thin pieces of sorb attached to the body of equipment. Similarly I read years ago that Naim was using sorb inside its equipment and one of the Schitt engineers personally told me that they also used it, although I didn't get the details of what equipment. But the need to damp headphones seems to have been mostly missed. Even now when we know that Sennheiser is damping the HD800 and that Grado has a new line of damped phones, the message is not getting out. There is a fanboy, flavor-of-the-month mentality in many of the forums, people are convinced that their preferred phone is the best and the posts just feed on each other. They don't follow the field very broadly. Stax people seem convinced that quality has all to do with the driver and little else. And having spent hundreds, if not thousands for a phone people don't want to hear that it still has design issues. However as the manufacturers start competing in this area I expect that the importance of this aspect of design will come to the fore and then buyers of current phones are going to realize that their current models are obsolete unless they can figure out how to damp them.