Music Master Bass Amp Mafia

I got turned on to these by Robbie D of the TDPRI and catnine over on the FDP. Hearing two cool cats singing the praises of such a funky stepchild of a Fender amp got my attention. When I learned how relatively affordable they were/are I really got interested. 12 inches of tube tone for cheap? I'm in.

I have gone through a few of these over the years but recently settled on this early 6AQ5 one:

http://www.tdpri.com/telephoto/data/500/MMBstepsRotated_Medium_.JPG

Bone stock except for the tubes - three RCA's - and, at the moment, a Weber Sig Alnico. Truth be told, for at home play the stock speaker in this thing sounded great for my low-fi hacking. I may end up going back to it.

I have also decided to leave the tone circuit alone on this one - although I will install an in-line fuse soon to protect the trannys.

Step up and show me yours!

Nice one, Vicious. Poor man's Deluxe....I love mine.

This one's got the 6v6's. Changed the input to a more standard "Fender" arrangement, i.e. 68K and 1Meg resistors and shorted that .047uF cap out of circuit. Sounded really good with a RI Jensen P12Q but wound up with the C12N due to the fact I noodle with a bass on it occasionally. The alnico couldn't take it, the N does fine. I've since added a 1/4" socket/plug connection for the speaker. Made it easier to hook to diferent speaker cabs and such.

Dan

edgetone:

That thing is CLEAN! Thanks for posting.

She'd been around the block a time or two when I met her....

Had one - but good such a good offer on it (well over then-current value) I had to sell! Highly recommended little amp.

Here is a good legible copy of the MMB amp schematic:

http://www.tdpri.com/telephoto/data/500/medium/mmb_schematic_Medium_.jpg

Here is an original schematic for a '74 6AQ5 version MMB
Kinda wish I still had mine...

http://i280.photobucket.com/albums/kk163/pchilson/MusicMaster_Schematic_1152-1.png

[QUOTE=pchilson;2130503]Here is an original schematic for a '74 6AQ5 version MMB
Kinda wish I still had mine...

Thanks for that - I had not previously seen a schematic specifically referencing the 6AQ5 version.

Here's mine lurking in the right upper corner... it's a modded version with EL84's (or 34's... how to remember that?)
http://i532.photobucket.com/albums/ee324/chesterburger/teletjastyrkaritpanpienempi.jpg

Nice rig, varakeef. The 6AQ5 model, right?

Aside from the feet and tone knob, any other modifications?

Nice rig, varakeef. The 6AQ5 model, right?

Aside from the feet and tone knob, any other modifications?

I think it is 6AQ5, 1974 I guess.

It's modded to use different tubes (EL34/84?) since the ones they normally would use were hard to find here when the mod was excecuted (in the early nineties). They probably still are.

I have no idea what the mod exactly is, I just know what tubes to stick in there.

I believe the 6BQ5 is "close" to the el84 and so that is likely the tube it was modded to accept. '74 sounds right. Cool amp.

It's modded to use different tubes (EL34/84?)


These are very different tubes. I would guess they modded to the EL84.

I just know what tubes to stick in there.
Only one type would fit the socket.

Here's mine. Yeah, I'm in the happy camp with MMB's. They are little tone monsters. I picked up an old '65 Jensen P12R for this one and it really stepped it up. This thing will really grind with a P-90. I found this amp at an old obscure flea market about a year ago for $40.

http://www.tdpri.com/telephoto/data/539/medium/IMGP0026.JPG

These are very different tubes. I would guess they modded to the EL84. Only one type would fit the socket.

Yep... and I have a tube chart glued on the back of the amp where the right type is printed on. So I know but I just can't remember that kind of info by heart. The flaws of human brain. :mrgreen:

I hear ya! Use it or lose it...