Speed Control


I've had a Classic 3 for about 1 1/2 years. When I first bought it, I used the KAB strobe to determine it was running spot on 33 1/3 RPM.

Recently I added an SDS. At 60hz it was running fast. With the SDS adjusted to 59.81hz, it runs at 33 1/3 RPM. Any ideas on the impact of -.19hz difference in speed?

At the correct speed it has a much wider soundstage. It sounds like it is playing in a room much larger than my actual room. I have a lot of acoustical room treatment (absorption and diffusion) so that my contribute to the difference.

My system is Benz LP (re-tipped) > Classic 3 > Sutherland Hubble > VK32SE > VK75SE > Eggleston Rosa. I use the record clamp and ring.
bigby

Showing 2 responses by brf

A SDS is a great unit for equalizing the variances in pulley, platter and belt machine tolerances. Very few people who run SDS have them set for exact 60 hz and achieve exact 33 1/3 speed. You situation is completely normal.
AC motors are sync to the line frequency not the voltage. Line frequency in the US is highly regulated and controlled and does not deviate as much as line voltage.

If you use the Platter Speed test record and associated mobile app, you can set you table's speed compensated for stylus drag.