The type of isolation/coupling to use, and where, and the "amount" of such is a matter of tuning (trial and error). I have never found it to be the case that more is necessarily better. It is possible to end up with a dry, sterile and harmonically bleached sound with too much of what is supposedly a good thing.
I have generally found the biggest effect to be under speakers. Often, the most commonly used device, the pointed spike (really a coupler, not an isolation device), is NOT the right approach over something like a suspended wood floor. In those instances, a platform with a foam type core to absorbs vibration is better than coupling through spikes (e.g., a Symposium Svelte shelf).
After speakers, I would address source components like turntables and CD players. These are sensitive components, but again, sometimes additional isolation is not what a system needs so it is a case of trying different things. I once helped with a trial of different shelves/devices under an Aero Capitole CD player that sounded surprisingly much worse with almost anything under it that is suppose to help with supression of vibration. The designer must have tuned his component for just what was needed (it came with something like Black Diamond cones for feet). My own CD player is somewhat immune to treatment--it doesn't sound that much different with special shelves, rollerblocks, etc.
In short, every system and component is different, so no single magic bullet works in all cases.
I have generally found the biggest effect to be under speakers. Often, the most commonly used device, the pointed spike (really a coupler, not an isolation device), is NOT the right approach over something like a suspended wood floor. In those instances, a platform with a foam type core to absorbs vibration is better than coupling through spikes (e.g., a Symposium Svelte shelf).
After speakers, I would address source components like turntables and CD players. These are sensitive components, but again, sometimes additional isolation is not what a system needs so it is a case of trying different things. I once helped with a trial of different shelves/devices under an Aero Capitole CD player that sounded surprisingly much worse with almost anything under it that is suppose to help with supression of vibration. The designer must have tuned his component for just what was needed (it came with something like Black Diamond cones for feet). My own CD player is somewhat immune to treatment--it doesn't sound that much different with special shelves, rollerblocks, etc.
In short, every system and component is different, so no single magic bullet works in all cases.