Hi all,
A friend of mine has a Maverick that "just quit" one night. Actually didn't quit but lost a lot of power and is distorted.
I opened it up and found a grid resistor that was about burnt in half. I replace that but no change in symptoms.
The voltages are in line with the schematic, I touched up some suspect looking solder joints, etc.
I'm not a great tech but usually manage to repair things.
This one has me stumped.
Tried different tubes(all of them) preamp,one at a time. Power and rectifier seem to be ok too.
Any help is appreciated.
Rick
Mesa Maverick problem
Moderators: pompeiisneaks, Colossal
Mesa Maverick problem
Building amps, one wipf of fumes at a time.
Re: Mesa Maverick problem
it has an FX loops isolate the problem to preamp or power stage.
tubes = power and bads ones sound distorted. after you isolate the location explore the tube sockets and surrounding components.
you may need to replace additional parts around the burned resistor... Do you know why it burned? If you can figure out what triggered it to burn you should be able to fix the problem.
tubes = power and bads ones sound distorted. after you isolate the location explore the tube sockets and surrounding components.
you may need to replace additional parts around the burned resistor... Do you know why it burned? If you can figure out what triggered it to burn you should be able to fix the problem.
My Daughter Build Stone Henge
Re: Mesa Maverick problem
Thanks for the reply.
It does have a FX loop and I have done that.
Don't know why the grid resistor went, just one of them on one of the power tubes. I've subbed in known good power tubes to no avail.
Output tranny?
It does have a FX loop and I have done that.
Don't know why the grid resistor went, just one of them on one of the power tubes. I've subbed in known good power tubes to no avail.
Output tranny?
Building amps, one wipf of fumes at a time.
Re: Mesa Maverick problem
Ok so it the issue in the preamp or the power section?
Once you know you can quickly go over that section.
The resistor most likely blew from a tube failing.
Mesa Boogie require matched factory tubes unless the amp has an adjustable bias mod. It's Mesa's way of keeping the customer coming back.
It's Possible the OT is shorting thought the OT is pretty robust. Test it.
If you aren't comfortable testing the OT take it to a tech. the fact you get signal at all leaves me doubting it's the OT.
Look around the area of the burnt component see if anything else took a hit. Clean the tube sockets.
I think you are over looking something. how was your soldering when you put in the new component? Did you take the board off to get to the solder traces?
Have you tried the OT on different impedance settings?
Once you know you can quickly go over that section.
The resistor most likely blew from a tube failing.
Mesa Boogie require matched factory tubes unless the amp has an adjustable bias mod. It's Mesa's way of keeping the customer coming back.
It's Possible the OT is shorting thought the OT is pretty robust. Test it.
If you aren't comfortable testing the OT take it to a tech. the fact you get signal at all leaves me doubting it's the OT.
Look around the area of the burnt component see if anything else took a hit. Clean the tube sockets.
I think you are over looking something. how was your soldering when you put in the new component? Did you take the board off to get to the solder traces?
Have you tried the OT on different impedance settings?
My Daughter Build Stone Henge
Re: Mesa Maverick problem
My Daughter Build Stone Henge
Re: Mesa Maverick problem
try cleaning the FX loop contacts on the jacks.
I just cruised the Boogie Forum a half dozen other Mavericks have had a similar issue. You can test it by pluggin in a jumper cable to bridge the FX loop if the volume comes back up clean / replace the jacks.
I just cruised the Boogie Forum a half dozen other Mavericks have had a similar issue. You can test it by pluggin in a jumper cable to bridge the FX loop if the volume comes back up clean / replace the jacks.
My Daughter Build Stone Henge
Re: Mesa Maverick problem
A quick lunch time reply.
Thank You so much for the info.
I do want to get better at this.
Tonight I'll have the whole evening to devote to this amp.
I'm not a member of the Mesa forum so I couldn't use the search function, I can do that this evening.
I'll also check the things you've suggested. The reason i came to this forum is the level of experience here and the willingness to help anyone with an interest. Thanks again.
Thank You so much for the info.
I do want to get better at this.
Tonight I'll have the whole evening to devote to this amp.
I'm not a member of the Mesa forum so I couldn't use the search function, I can do that this evening.
I'll also check the things you've suggested. The reason i came to this forum is the level of experience here and the willingness to help anyone with an interest. Thanks again.
Building amps, one wipf of fumes at a time.