a good mixer will be able to set the speed using the pitch slider that good that he/she dont need to touch it to keep it in time...it stays in on its own.
Only a small push/shove will be needed every now and then and can be done either by touching the platter/record/spindle or moving the pitch slider a little.........but this should be hardly ever needed if the speed has been set correctly...
that my theroy.....just set the pitch correctely and life is easier.
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