Thoughts On Turntable Clamps And Weights

This leaves out a crucial part of what happens when one placing a floppy disc of vinyl on a surface. There will be a cavity below that shift from center to front of the disc when adding a clamp.

Tap the disc with your nail and you clearly hear the hollow space below. Thinking any cartridge will not "hear" and reproduce this cavity is denying the acoustics of that environment.

Me thinks, a vacuum is the only way to couple disc and platter into one acoustic unit. Tap that sandwich and you will only hear the sound of your nail striking the record, nothing more.

I would not consider any turntable, in any price range without a proper vacuum hold.

It is as basic an issue as firm speed stability and lack of bearing noise.

My VPI has a periphery clamp and weight.....works very well, but it was designed for its use.

I contacted Pro-Ject regarding clamps and weights but did not receive a response.   

@lewm , @terry9 

Wow, hold on now. Lew, there is supposed to be a firm rubber washer about 0.5 to 1mm thick and 1/2 to 3/4" in diameter over the spindle, under the record. The Sota REFEX clamp contacts the label only at its very edge. When you tighten the clamp down the edge of the label is forced down into the label rebate flexing the record into the platter/mat. This will remove small warps and flatten dished records. It is way better than just a record weight. SME, Avid, Oracle, Kuzma and Dohmann use this method. It is not as good as vacuum clamping but a bunch less complicated and it will work everytime. Vacuum clamping will fail if the record is badly dished or too warped. 

@stringreen , IMHO periphery clamps are a Pita and an accident waiting to happen. They are totally unnecessary if you get a reflex clamp like the SOTA.