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Old 01-03-2018, 03:39 PM
cleeds cleeds is offline
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Quote:
Originally Posted by VicsVinyls View Post
... as the needle drags over the record the speed can change b/c the grooves are different as it goes. You have an SDS to maintain the speed, isn't this the whole reason for the SDS? ...
I'm not sure what you mean when you say "the grooves are different" or why that would affect platter speed. Frankly, it's very difficult to imagine that a diamond stylus with a tiny footprint tracking an album at a couple of grams on a 22-pound platter can be subject to groove-induced speed variation.

The role of the SDS is to filter the AC power - actually, it regenerates it - and allow the turntable speed to be set precisely. That's how it maintains speed - it doesn't use a servo to correct for any speed deviation.
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