View Single Post
Old 13th Dec 2018, 10:50 am   #10
PsychMan
Octode
 
PsychMan's Avatar
 
Join Date: Jun 2013
Location: Fleet, Hampshire, UK
Posts: 1,764
Default Re: Nice Way To Measure Turntable Speed

I think tracking weight and the effect of the stylus is somewhat irrelevant here, as this is simply a replacement for strobe discs, which do not consider those factors either.

Strobes that work against platters are usually built into turntables and give a visual indication of speed with a record playing. For what we do - which largely concerns auto changers from the 50s - 70s, the most effective method is a strobe disc, or this app.

I haven't checked it for accuracy, but will do by comparing it to my SL1210s. I sometimes put a strobe disc on them and adjust the pitch back a few % to get an idea what 2% slower looks like on a strobe disc.

I think actually a few percent is quite significant. In numerical terms a very small amount, but incredibly audible in musical terms. To me anyway!

Precision is not something often found in old turntable motors, but its nice to know just how far out something is. An example being an RC210 Ive just worked on, despite stripping and oiling the motor, bearings etc, it appeared fairly slow on the strobe. Comparing with the SL1210, it looked to be 1-2% slow. I brought it in from the cold workshop, let it get t room temperature, run it for 10 mins, more like 0.5 - 1% now - probably the best it will get.
PsychMan is offline