Mesa Boogie Dual Rectifier Problems

If you are having trouble with any of the following boogie symptoms then I may be able to help you out as I have spent more than my fair share of time on these metallic monsters.

Mesa Boogie amps are reveered by players for their unique sound. But for us Amp techs they can be a pain.  Not only do they use unique to Mesa Boogie components but they also choose to hide  circuit board markings so that diagnosis can be tricky they are helpful with schematics but they schematics are not easy to connect with the PCB in the amp as there are no component references.

Special Boogie Symptoms I have come across include:

Intermittent output, or rather occasional fading output.  This is a common problem in amps usually caused by an unreliable connection somewhere in the signal chain.  Usually such a fault will be either permanent or intermittent and respond to thump on the cabinet.  With Boogie it is extra annoying as the intermittent nature is temperature / time related and of course it will let you down when you really need it to be reliable.

Bias LED flicker

Bias light flicker – check the little red or green light on the rear when the output fades.  Sometimes the output fading and the light flicker coincide together and sometimes not.

Channel Switching Problems

Channel switching strangeness including flicker,  dim lights, no lights etc.  Seems more noticable on footswitch but that actually it is usually the same with the rear switch.