Isolation and Harsh Highs?

Hello I isolated my tube preamp with some equa footers. I notice a lot more detail and the sound is much cleaner and focused but I also notice the high are now kinda of harsh. Currently my system is on Lovan glass shelves and I have a couple maple platforms coming which will hopefully help matters. I would imagine the isolation revealed some brightness in my system I had not noticed before. Any ideas?

My System is
VPI Scout/Blackbird Cart/SDS/on Ginkgo Cloud 9 Iso platform
Granite Audio 770fp preamp
B and K Reference 2220 Amp
AQ Diamondback IC
Sonus Faber Concetos on sand filled stands