Best Isolation Device for Speakers?

First thing is, you can't "isolate" the speakers. The speakers are a strongly vibrating component, and they cannot be isolated from themselves, ever. If you think the cabinets are "dead", the driver baskets and cones are vibrating like mad anyway.

The ONLY way to deal with a situation like this is by a well engineered vibration drain system such as the Sistrum speaker platforms, or the Audiopoints. I have tried both, and the Sistrum platforms exceed the Audiopoints, in terms of performance. They should, because they are the next step up, and they cost more than the Audiopoints. But they are significantly better.

ANY soft type of material like rubber blocks or the like, will allow slight movement of the speaker in a fore/aft axis, thereby smearing attack and dynamics and coherence by doppler. They will also eliminate the path for vibrations to exit, and they are doomed to circulate and re-circulate in the speaker.

I have a suspended floor, and the Sistrum Platforms and Audiopoints have made a remarkable improvment in sound, especially in the speakers.

Another interesting benefit, is that you get another db or two efficiency out of your speakers, because they are operating in a more efficient mode, when the vibrations are properly removed from the motor. This is not a joke, or exaggeration. This is a real increase in speaker efficiency, and I have experienced it for myself.

I recently left the confines of working for a retailer that sold Thiel speakers..I know from experience the Thiel's will improve as much as any speaker I have ever tried either the Audiopoints or the Sistrum platforms on. It is because of the Thiel cabinet mass and density that the improvement will be so large..It is imperative to match the proper size Audiopoint to the respective Thiel product..Again because of their mass and the great amount of excess energy that these very dense cabinets do store..Sistrum Sp101 platforms are what I personally use under my still almost Dunlavy SCIV's..Tom

Twl is correct. I too have measured an increase in spl when using the Sistrum of about 1.5 to 2db.. This was measured in the retail showroom with an Audiocontrol RTA..Oh and these are not isolation devices and if you were to try to dampen or isolate the Thiels they would only gain in bloat and blurr.Tom

This thread is of great interest to me currently. I have recently placed my 5As on a piece of MDF over the carpet on a large second floor listening room over the garage. I did this to help me move them around for purposes of testing. What I discovered is that the speakers had much more life in them on the MDF. The highs were much clearer and the vocals more magical. After listening for a couple of weeks, I put them back on the carpet in exactly the same position and the life was sucked back out.
I had previously believed that the speakers were best off coupled to the floor, and the 5As have cones which I assumed were coupling devices. Now I realize that for reasons I can't explain, the image is much better with a degree of isolation.
Let me also say that the cones may not have penetrated the thick carpet and pad very successfully.
Can anyone help here? Should I be considering a better isolation platform under the speakers? Or should I be cutting through the carpet to let the cones get to the subfloor? Can an of the Systrum technology help? I looked at their stands and I don't think they can mate to the botton of the 5A with its sub opening and grill.
Thanks for any help.

You need to call the boys at Starsound about the use of Sistrum with your speakers..You should be able to position the triangle of the Sistrum in a way that will not interfere with the driver on the bottom..They will help a lot. Even the use of Audiopoints 1.5 in will be large..Tom