I have talked to Hagstrom and they will not commit to any specific ohm values other than a range of 500 to 1m ohms.
REALLY!!!! Strange. I have always found then VERY helpful.
Maybe what they are saying is that any value in the range will work fine. The main tip I acn give you is get linear taper pots. Audio taper is logrithmic.. and will not work.
If you are goinmg to gear the mechanical linkage, maybe look for multi-turn pots. But you'll need to do the gear ratio calcs so that you get the full range of the pot's values.
best,
................john
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