Flint said:
I wouldn't call it decoupling when a 100lbs sub if focusing all the weight into four tiny feet and compressing all of the air out of the carpet and foam underneath. It may be better than spikes (the worst thing ever for speakers), but factor hard rubber or plastic feet are not as good as some sort of material which can actually give and take a little bit.
Of course, this gets to the conversation I was having in the "Empirical Observation" thread. Improving a system from 97% close to perfection to 97.5% close to perfection isn't a big deal. A good isolation may only be 1% better than not having it and thus unnecessary in the big picture. But isolation is good.
With respect to the underlined passage above, I suspect that you've erred on the low side. My personal experience is that it can make a very noticeable difference.
I think though, that we need to also look at the notion of "better."
I've been in and listened to quite a few members' home theatres. I have been impressed by all of them. (We members do tend to put a lot more into our systems than the "average" person - so I would expect no less!)
However there have been significant differences in sound - and in bass performance in particular. I'm not going to mention names, but the biggest noticeable difference, to me, has been the amount of, or lack of, bass transferred to the seating position through the rooms' structure - rather than through sound alone.
The effect ranges from "buttkickers completely off" to "buttkickers at maximum Captain!"
NB: This in no way implies better or worse. These systems are doing what the members want of them.
However I have also noticed a very significant correlation in the degree of this effect depending on the room and how the sub(s) are coupled (or not) to the floor.
I'll mention my room: all subs on solid concrete slab. Buttkicker effect completely off.
Whether it's the SVS product, or something else, I have no doubt that there will be a very noticeable difference in many cases. It may not be better - and in fact the owners may be disappointed with the result (in that the buttkicking gets turned off - or at least turned down.) But there will be a difference.
However in cases where that structural transmission of energy is exciting undesired vibrations in other items in the room / house (which I don't recall happening in any of the HTs that I visited) then this would probably be considered "better."
Assuming that this new SVS product works as described, I, like Flint, feel that $50 is not an unreasonable asking price - especially for those who really want and need the isolation promised by SVS.
Jeff
ps. And this might very well be the easiest SVS product ever to try first and return later if not completely satisfied!