cardinal
Well-known member
Mesa Mark III. Asking $1750 shipped.
Just back from service from Mike B. I'll copy his service notes below.
According to Mike, it's a purple stripe that at some point was updated to red, likely by him. Note that is not the 105PT. It's the 100PT, which Mike thought was like what was used with the IIA or IIB. No idea how it ended up in this amp. Huge chunk of metal.
Sounds killer. I had a C+ a while back and thought they sounded the same until this amp started acting up. Mike B got it all fixed up and it's good to go.
Mesa service notes:
The bias supply caps were both open, the bias set resistor was missing, bias was close to correct but humming. Replace all the “remaining” original electrolytic caps. Updated the Class A sockets with screen and grid resistors to allow stability with different sorts of power tubes. This was the “gacking” sounds from the power amp. Re-did some of the cap replacement work and secured with glue as needed. Did the reverb Glitch update. Upgraded the .1/400 caps at V5 to.1/630 volt. Removed main board to replace damaged V1 socket as needed. Replace the V1 tube shield. Clean all the pots pulls pre sockets jacks etc. Cleaned out loose reverb tank and restored all connections, remounted proper with new all steel shield plate. Cleaned and lubed the EQ sliders, working OK, still scratchy when cold but no intermittents. Replace EQ sliders as agreed. Labor 4 hrs. working good with bench tubes. NOTE*** THE CHASSIS SCREWTHREADS ARE RETAPPED AND SCREWS ARE NEW **DO NOT EVERTIGHTEN!! THREAD ARE GETTING THIN!!
Just back from service from Mike B. I'll copy his service notes below.
According to Mike, it's a purple stripe that at some point was updated to red, likely by him. Note that is not the 105PT. It's the 100PT, which Mike thought was like what was used with the IIA or IIB. No idea how it ended up in this amp. Huge chunk of metal.
Sounds killer. I had a C+ a while back and thought they sounded the same until this amp started acting up. Mike B got it all fixed up and it's good to go.
Mesa service notes:
The bias supply caps were both open, the bias set resistor was missing, bias was close to correct but humming. Replace all the “remaining” original electrolytic caps. Updated the Class A sockets with screen and grid resistors to allow stability with different sorts of power tubes. This was the “gacking” sounds from the power amp. Re-did some of the cap replacement work and secured with glue as needed. Did the reverb Glitch update. Upgraded the .1/400 caps at V5 to.1/630 volt. Removed main board to replace damaged V1 socket as needed. Replace the V1 tube shield. Clean all the pots pulls pre sockets jacks etc. Cleaned out loose reverb tank and restored all connections, remounted proper with new all steel shield plate. Cleaned and lubed the EQ sliders, working OK, still scratchy when cold but no intermittents. Replace EQ sliders as agreed. Labor 4 hrs. working good with bench tubes. NOTE*** THE CHASSIS SCREWTHREADS ARE RETAPPED AND SCREWS ARE NEW **DO NOT EVERTIGHTEN!! THREAD ARE GETTING THIN!!
