Measure My Turntable Speed

"it worked great and cost $20, with an accuracy of +/- 0.05%. Plus you want you can play an LP for stylus drag while you measure. This is the only way to go!"

+/-0.05%? Unless it has a calibration sticker traceable back to the Bureau of Standards- no way. +/- 0.05% is the domain of very expensive laboratory grade equipment. A stobe-disc and fluorescent light is the most effective method. It leverages the Power Company's technology and accuracy- and it is dirt cheap. Plus, you can check the speed while playing a record.

Gerardff... how very interesting and simple.

Exceedingly dumb question (but I have to ask it anyway):

Does the accuracy of the measurement of a Digital Photo Laser Tachometer matter at to the placing of the reflective tape: whether the reflective tape is on the outer edge of the LP, toward the center, or somewhere in between?

Thanks & have an excellent new year's eve and new year.

:) listening,

Ed

.

I made my own strobe for pocket change, when I was making 3$/hr as a kid.

Used an NE-2 / socket and diode. changes AC to half wave and pulses the neon bulb on/off. Perfect 60hz. I scavanged a cord/plug from something and used a plastic tube for a mount. No exposed AC and worked fine. My TT at the time had 'barcode' circling the spindle for 45/33rpm at 50 or 60hz.

90$ for a strobe? nutty.

I had another idea.
Test tone CD and a test tone record.

Play them both, switch between them as you adjust TT speed until no pitch change between them.

If you have 2 systems available, you could even 'beat' the frequencies generated and get very close to perfect. Using that method you could even do drift checks.

Does anyone have any problem with CD pitch accuracy or repeatability?
Are there any speed variable CD players?