To Couple or Decouple?

You need decoupling on that floor, and your Crescendos deserve Stillpoints Ultra 5s. Expensive but worth it.

Vibrapods (or things like them) are MUCH less expensive than what I consider to be over-machined accessory porn (!) stuff like Stillpoints, and they accomplish the same thing...turning vibration into heat or at least decoupling direct speaker vibration from a floor. I'm waiting for magnetic levitation pods for speakers...should cost as much as my car.

I second the Herbies gliders, if only to make moving/positioning the speakers very easy. Much disagreement about whether to couple/decouple. My experience is that unless you play at very high db's it might not matter. YMMV

It's a very good question that I really had to think about. I would say decouple first then couple perhaps if all else fails.

That's not to say that coupling might not sound better in some cases but each case of coupling will produce different results. So how can a speaker be designed to couple when every case is different? Therefore decouple to achieve what was intended best. In most cases coupling will result in hearing the room more rather than just the speakers.

I recently added a pair of isoacoustic speaker stands designed to decouple and these have helped make a believer out of me. I then added a pair of auralex sub dude isolation platforms under my ohm speakers in my family room with common suspended plywood flooring and the results in both cases are a revelation.

Symposium will custom make isolation platform not cheap but its the best.