Does this mod even exist for a MkIII?

[Ed Mullins]

I'm interested in a mod for my MkIII that would assign Simul-class power to the rhythm channels and Class A to the lead channel. In my mind this would be similar to the EQ AUTO function which assigns the EQ to the lead channel. Does anyone know if this mod is possible and/or availble through Mike B. at Mesa Boogie?

 

[Boogiebabies]

Not that I am aware of. It would have to have a heavy duty relay and some sort of switching device. You would have to have a relay off of the lead LDR that pulls the inner sockets to ground when you switch. You can replace the simul class / class a switch with a footswith. All it does is switch out the ground on the 6L6/Inner sockets. You may have to do a small tap dance, but it would accomplish what you are looking to do. The MK IV has a Simul/Class A footswitch. A very cool feature, but not automatic.

If I get a chance I will look at the schematic and see if I can do it.

The Road King has an amazing array of not only tube switching but cabinet switching. The relays are very large, but the switching matrix is awfully complicated. Rather amazing.

 

[Ed Mullins]

Thanks very much for the info. Making the Simul-class/Class A switch footswitchable might be good enough for me. Is that an easy mod or should I send the amp back to Mike B.?