Critical mass CS2. Prior to moving my whole system to these, I was using footers that cost $1000/- per piece (list) and thought they were brilliant. But the CS2 footers make everything else seem like a joke. About $1200 per set of the lowest series.
Have been experimenting with footers from the mid 90's and been thru all the latest fads over the years. Stay away from all rubber based ones. Yes, rubber does absorb vibration....BUT a lot of it gets reflected back after a delay. This is the reason for the 'soft' sound associated with sorbothane et al
After rubber came cones, then these were improved by bearings. Both types help, cones by acting as a sort of mechanical valve for vibration, and bearings by obstructing the transmission path of vibration. Different brands are more or less effective.
CS2 is a completely new concept - the composites and structure drain away vibration in a way I confess I don't understand, but the effect is undeniable.
I would strongly suggest putting all component upgrades on hold and investing instead in these footers. Once 'burned in' (in my system 300 - 400 hours playing time) one tends to find what one was looking for without messing around with component and cable (also a component?) upgrades.
Best wishes
