VPI Analogue Drive System

I moved my motor drive belt up to the top slot on the motor drive pulley which effectively lowered my 3150 test tone from 3160 to 3149 on my PlatterSpeed app.  There was a significant improvement in sound quality with all my MC cartridges (I have 4 of them).  This obviously didn't cost me anything and I should probably have done it awhile ago, but I've just started paying attention to this tweak.  So far I'm not running out to buy anything yet.

Running your TT at the right speed (or nearly so) is not a tweak.  It's just a very basic thing everyone should do, like leveling the platter.

Melm:

Sorry.  Wrong word.  At this point I'm almost ready to take your advice not to buy anything and maybe the DIY components that Phoenix Engineering used to make will be available again.
So far no one who has bought the ADS has responded as to how great it is.

All the "speed control" fanatics are completely missing the point and the REAL issue.  Speed control is NOT the issue.  It is VOLTAGE control.  At wall voltages, the motor will generate pulses that are carried to the table through the belt (or drive).  Reducing the voltage will reduce the magnitude of the pulses and fix the noise issue.  THAT is the reason to get one of these units.  A variostat will do the job at a fraction of the price of a "speed control."  Start the table at full voltage then reduce to 70 volts or so when it's time to drop the needle.

Doesn't my SDS that drives my turntable do what the ADS does??  What's the difference - is one better than the other, etc.