mike gilmour

I'd agree to an extent. Since this thread about clamps started I've run some
listening tests comparing both vacuum Vs spindle clamping. On my vacuum
clamp SOTA turntable, it is trivially easy to see the affects by switching
out vacuum pump. With the pump on there is a discernibly lower noise floor
i.e a 'blacker' background less surface noise, imaging and general focus
improves. Without vacuum but using the SOTA centre 'pull down' clamp the
benefits are not as good but better than no clamp at all. I don't have the
periphery clamping ring so I can't comment about that one. I've also heard
the Basis vacuum turntable that exhibited similiar results.
This suggest to me that centre clamping athough good is not as successful as
vacuum clamping.
Just my 2p's worth...

Mike