Rega Planar 25 adjustments


I know that one needs to use an alignment tool, and the tool to calibrate the weight/force the needle applies to the record, adjusting the weight on the back of the tonearm that is on the arm itself.

But at the base of the tonearm there is a dial adjustment with the numbers 1, 2, and 3. WHat does this adjust? How does one know how it should be set?
anti-skate, try setting it about .5 to 1 lower the your tracking force, that's at least a good place to start.
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I found that there is no better mod to the P25 than to get it off of those rubber feet. I use 3 Cardas wood blocks around the wooden surround to great satisfaction.