How is tone affected by input impedance (if at all)?

[lmacmil]

I built the Jack Orman MOSFET booster and am using it with an acoustic guitar equipped with a K&K Pure Western (passive) pickup.  I am doing open mic nights and plug into the house mixer.  I usually leave the gain fairly low (min gain is 6 db according to the MOSFET booster info).

The MOSFET booster has a 10 meg input impedance which seems to be typical for acoustic guitar preamps.  K&K sells their own preamp and it only has a 1 meg input impedance so I'm thinking they must have determined that's a better match to their pickup.

Wondering in general, what the effect would be of lowering the input impedance from 10 to 1 meg?

[R.G.]

Wondering in general, what the effect would be of lowering the input impedance from 10 to 1 meg?

Essentially none. Maybe a tiny bit more treble.

The deal is that pickups are inductive. Inductors have a rising impedance with frequency. Standard non-piezo pickups peak out at about 100K to 200K of impedance at the upper frequencies. If the input impedance is not more than 10x as big (that's where the 1M comes from) then you lose treble. You get diminishing returns by making it ever bigger. 10M may let a little more treble through, depends on the pickup.