Edition Tube 20th Anniversary

[plexi50]

I have a Huges & Kettner Edition Tube 20th Anniversary that has a nasty pop when using the footswitch or front panel channel switch

Pretty darn good sounding amplifier otherwise / Schematic PDF below

[tubeswell]

Gawd! What a horrible looking schematic! Tried looking at the (on-board) switching circuit?

[plexi50]

Gawd! What a horrible looking schematic! Tried looking at the (on-board) switching circuit?

Yeah i tried to figure it out. Im still picking at it

[RicharD]

Check D18 and C51. 

[plexi50]

Check D18 and C51. 

D18 & C51 are good. I swaped them out anyway but still major pop

[RicharD]

Maybe I picked the wrong relay?  That is a busy schematic.  Check D17 & C50.  What I as suspecting is one of the relay coil protection circuits.

[plexi50]

Maybe I picked the wrong relay?  That is a busy schematic.  Check D17 & C50.  What I as suspecting is one of the relay coil protection circuits.

Yes i looked at D17 & C50 and they are good as well. Im still trying to figure the schematic out

[John]

I don't guess it could be something as simple as a sketchy ground at either the jack, or S1/S2?