The way it was explained to me is that most cleaning brushes, while removing some dust, can also force some dust that was on the surface down into the record groove where it can be impacted by the stylus tip and cause record damage.
Linn: Most record cleaning devices do more harm than good. The dust that inevitably collects on records is not harmful: it's on the surface, not in the grooves containing the signal. Attempts to remove the dust usually force the dust down into the grooves, where it does damage. The best method of cleaning records is to let the stylus remove the dust then clean it. (excerpt from "How to Care for Records" as found in the Linn Magazine)
One of the nice things about this idea, shared by Rega, is that playing records becomes a simpler, more straightforward operation. You just take the record out of its sleeve, play it, then put it back in the sleeve.
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