Hi millercarbon! Glad to have you back!
@nhmanmtb , I rode mountain bikes for decades here in New Hampshire. Our favorite was always Massabesic. My kids would do the logroll over and over again laughing hysterically.
Your best bet is to order a MinusK platform tuned for 150 lb and put it directly under the turntable. This the ultimate isolation both vertically and laterally. Nothing else comes close. There are painfully few other options that really work. Most of it is just wishful thinking.