For isolation, I have tried: HRS Nimbus Couplers, M3, solid 4" thick birch ply, granite slabs, Auralex isolation, slate slabs, brass weights, Artesania weights, vibrapod. Among all of these, The Ultra 5 stands alone in its ability to deliver clean, delineated notes. Time and again across 9 different components, it stood alone in these important element (for me) of isolation. Only the HRS came close, and in the case of the Pre and DAC, I found in the end that I preferred HRS M3s in the overall balance. But for speakers, power units, transport, amp...I use Ultra 5s finding that the more I added, the more delineation of notes I got, the more syncopated rhythms became easily apparent, and the more depth, pace and extension I got...all effortlessly understandable. Each time I added Ultra 5s, I noticed a slight shaving of the upper mid to lower treble weight...but was always able to get it back if I carefully place the Ultra 5s under components 'just so'...and in most cases if I also added HRS Nimbus/Coupers on top of them. But this was to get back the tonal weight in the upper mids to lower treble. IN terms of clarity, nothing above has been better than the Ultra 5s. My two cents.