Mk IIA Reverb Question

Greetings and Salutations my fellow Boogie Brothers and Sisters, I wish you greater tone for the New Year!

Ok, enough of the BS. :lol:

I noticed recently that when I switch to the Lead channel, the reverb seems to disappear. I thought maybe it was because of the footswitch, but the same thing happens when I pull the knob to engage the Lead. It's there, just not as present as in the Clean channel.

Also, I've tried connecting footswitches (single and double) to the jack under the chassis, which should control either the Reverb or Gain Boost, but nothing happens.

Anybody else notice this (or have) the same issue with their Mk IIA?

Depending on which version of the IIA you have, particularly the early ones with the Teledyne channel switching relay, you will need to lower the series resistance going into the relay...

Mesa issued a service bulletin for this in 1980 which says to lower the lead channel series resistance to 150K for good lead reverb...you can go even lower...and play around with the balance between the 2 channels until you get something you like...

Much thanks!