Sandbox-style isolation

AFAIK, a sandbox with a segmented top plate is the only platform that can completely isolate all the TT elements from each other, while preserving a fixed, stable geometry between outboard motor, flywheel, and plinth. Any other system will tend to recirculate vibration across the horizontal surface of the platform.

Hi all,

Isolated segments of a top plate come at a cost - that of maintaining the correct speed relationship between the drive system and the platter. You might get better isolation, but it doesn't come for free.

In Galibiers (and by inference Teres, Redpoint, and ???), every time the coupling between motor and platter has improved, so has the sound.

Now, just like rubber belts in some designs, the net result can be an improvement. I think what we're looking at here is: (a) how much vibration you're sinking, and (b) does any of the movement inherent in this isolation strategy get masked by any compliance in the belt.

The bottom line is that there are no absolutes and the entire system needs to be considered as an ecosystem. What works in one context will not necessarily work in another.

On a related subject (and one I feel more absolute about), from time to time I find myself working hard to convince customers to NOT site their drive system on a separate stand from their turntable.

Picture two sky scrapers independently swaying in the breeze, and I think you can visualize the nature of the problem. Since no two areas on a floor vibrate identically, the two stands will move out of sync with each other. The higher the stand (in relation to its width and depth), the more this is exacerbated.

That's my story and I'm sticking to it ;-)

Cheers,
Thom @ Galibier

Cheers,
Thom @ Galibier

Thom, Segmented top plates sharing a single sandbox, each segment with an alumimum angle or aluminum heat sink anchored deep into the sand. Heavy mass-loaded plinth with heavy outboard motor. Do you really believe that the top plate segments will move relative to each other enough to cause even tiny shifts in geometry of drive train?

I can tell you from my own experience the single aluminum plate using the vibration sinks, per Thom's instructions, is superior to the segmented top plates I've tried. More refinement, resolution, more slam, solidity, greater dynamics. Now, I've thought about segmenting the aluminum plate, Thom's argument makes sense, I will not segment.

Do you really believe that the top plate segments will move relative to each other enough to cause even tiny shifts in geometry of drive train

Yes.

Based on the argument that these two pieces won't move independently, one could argue that isolation of any sort wouldn't help because all of this movement is so minute.

Ultimately we are all patently mad and arguing over small things, but as long as we're having fun with it, let the debate rage on.

Cheers,
Thom @ Galibier