Mark IV Overhaul:Send to Mesa or ??

[Allegron]

Greetings, Ric here. I have a MarkIV combo,purchased new in '91 or '92 that seems to need some major going over. In the past I've replaced various pots(due to the plastic shafts getting sheared off in transit); I've replaced the rotary switch that selects modes for the foot controller(which once again isn't functioning); and the amp gives off an irritating low frequency hum(with or without a guitar plugged in), therefore I have to turn the master volumes down to work around it; and I've re-tubed the amp with a kit from Eurotubes (except the 6l6's which I replaced with matched pairs of Svetlanas), and now my volume or power output has dropped about 50 percent. I know it's time for a major tuneup. maybe caps need replaced;maybe the tubes suck,biasing is off etc; maybe the foot controller problem lies outside of the rotary switch etc. My question is has anyone been in the same boat and what did you do to get the amp back to spec? Thanks for the time and any "feedback" Ric.

 

[LUCRETIA]

send to mesa for full check up.

 

[twally]

I don't have any experience with this. However, I have heard nothing but good things about sending your amp to Petaluma. If this was my situation, I would send the thing to Mesa and let the builders have a go with it.

JMHO,

TW