I run the EGDM at 18v. (Thanks Newarkwilder).
I've never altered the internal trim pot as I've always thought why try and fix something that isn't broken?
I use a Strat and a Tele into a Vibro King.
I read a thread on TGP where someone said said they did mess with the trim pot looking for something different/ better,
only to eventually return it to the stock setting convinced it was the optimum setting to begin with.
(see note below )
Regarding Mr. Juhl's description pages that come with his pedals-
I use suggested starting points for external knobs as a guide and happily tweak them.
People say trust your ears- but regarding inside the pedal,-
I've always trusted his ears especially if he tests pedals using Fender amps (among others).
So can you tell me how the trim pot is meant to alter the tone/ voicing
to be better suited to a particular amp/ set up etc. Especially if you use the EGDM with a Blackface style amp.
(Many who visit here are also regular Gear Page users/buyers/ sellers etc-in fact I discovered the BJF Forum through TGP! ).
Cheers.