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SME speed adjustment

I have been reading with much interest the thread about speed accuracy and the Timeline device.

I have an SME Model 10 turntable which has no speed adjustment on the motor controller. I use the KAB strobe and my table is fine, but I fear that if I have the chance to check it with the Timeline, and the speed is off, I will not be able to adjust it, so the exercise would be futile anyway. Currently, when the speed changes over time, I replace the belt, as SME suggests and this usually works.

Could someone suggest a method to adjust the speed on a motor controller that does not have such an option? Is there an aftermarket device that can be used to alter the voltage to the motor controller or some other method?

Any advice would be much appreciated. Thank you.
peterayer

Showing 4 responses by halcro

halcro's avatar
halcro
2,664 posts
 
Of course you're both correct :-)
The distance from the spindle to the wall in my example above.....is 350mm.

The problem with stylus drag is that one doesn't consciously hear it.
From all that I have seen, read and heard over the last 6 months........I imagine that the majority of turntable users might be experiencing this phenomenon and are quite happy?
It is only really when one hears the complete elimination of any speed inconsistency that an epiphany occurs?
halcro's avatar
halcro
2,664 posts
 
You may be worrying needlessly Peter?
It is not necessary to have the turntable revolve at precisely 33.33rpm to have good sound.
Orchestras around the world don't always base their pitch on the note A being at 440Hz. Anywhere +or-12Hz in pitch is quite acceptable.
This would relate to a shift in the Timeline mark on the wall of up to 1/2" every revolution of the platter.
As long as this shift is consistent.......you will have no speed-related issues.
The only way to find out....is to buy/borrow a Timeline.
The 'fear' is much worse than the knowledge :^)
Good luck.
halcro's avatar
halcro
2,664 posts
 
Sorry Tony,
Whilst I measured the distance from the turntable spindle to the wall at 350mm at right angles.....the laser line was actually projected approx. 400mm from the spindle to the wall at approx. 30 degrees.
Everything I said was approximate not expecting anyone to actually do the maths?
This was just to give Peter some relativity to his concerns :-)
Incidentally.....+6Hz from 440Hz @33.33 is 33.41rpm
+12Hz from 440Hz @33.33 is 33.48rpm
-6Hz from 440Hz @33.33 is 33.25rpm
-12Hz from 440Hz @33.33 is 33.18rpm
halcro's avatar
halcro
2,664 posts
 
Hi Tony,
I'm not into the maths :-)
I'm simply quoting the read-outs on the digital display of the TT-101 as I change the pitch in 6Hz increments.
Perhaps someone can help with the correct calculations?
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