• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Masco MA-35 rebuild

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi all.

First time posting here. Now that I'm retired and I'm spending alot of time restoring and building tube type amps from my 40 years of parts colecting (hording pack rat).

I've recently compleated the rebuilding of a Masco MA-35.

This thing was prety dirty but it was all there. The original circut used a 6V6 driving an interstage transformer to drive the PP 6L6s.

I've replaced that with the "Fender" type PI. I'm using the "Fender" tone stack feeding the PI. Also using the last fender preamp stage single triode just ahead of the tone stack.

This single triode is being used as a mixer for 3 diferant input preamp tubes. Each of these preamp inputs have there own 1/4" jack.

Input 1 is standard "Fender". Input 2 is a low gain 6C4 triode (1/2 of a 12au7). Input 3 is a high gain 6au6.

I replaced the filter caps with 10uf/600 v military oil filled. I've added a DC power supply for the filliments.

Another thing that seemed to be of original pore design was the placement of the preamp pots within very very close proximety to the output section.

Ive installed a metal devider to isolate all audio controls from the output section to eliminate any oscilations or instability.

You can crank the controls and all you here is a slight hisss.

I should have mentioned that this rebuild started with a complete chassis strip down and paint job. I've also retained the original output, power transformer and choke (iron).

I've also added a fan to keep the 6L6s kool.

I did not restore the faceplate, its a littel scuffed but quite usable. I've had guitar players, harp players and bass players all play through this amp.

They have all been very impressed. The unfortunet thing is I'm not a player. I just like building and restoring tube amps.

I would like any sugjestions on a fair market value and where I shuold offer this amp for sail.

I do have befor and after pictures if I can figure how to post them?

Thanks for any help.

Jerry
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.