The turn-off "thump" is not related to the operating dc offset. It will still be there. Best not to turn off the PICCOLO unless you are turning off the phono too.
jh
Guess I didn't make that clear...any mods to reduce offset have nothing to do with the behavior of the Piccolo on power-down.
I suggested selecting something other than phono simply to ensure that, if you have a FET phono stage, that there is no possibility of damage to the FET's, since even with power off, forward-biasing the FET's is a Bad Thing™. If the selector on a receiver or preamp is set to something other than phono, then the Piccolo is effectively disconnected from the phono stage, and its power-down behavior is moot.
