Hammond A0-29 Chassis Church Organ Amp Mutation, the "Holy Roller"

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tablebeast

Well-known member
Joined
Feb 8, 2005
Messages
147
Location
Forest City, NC, USA
I've been storing a half dozen old tube Hammond organs for years and just got around to digging into the first couple of them this week, with the intention of making a couple of modified instrument amps. At first I looked at an M-3 from about 1955, but it had the big, silver, 380-0-380 secondary power transformer and field coil speaker. With the voltage being too high for what I'm thinking about for this first project, I'll save that one for later...

Next I looked at an M-111 from about 1966. It was more of what I wanted in a parts donor. It had a later A0-29 chassis with the smaller, black, 320-0-320 power transformer. A separate reverb amp (A0-44 chassis) with its own tank and a total of three regular AlNiCo speakers were also lurking inside. Besides repurposing the amps, reverb tank and speakers, I plan to reuse some of the wood and other bits to build the modified cabinets. I'm planning on a 2x12 combo with the A0-29 and a 1x8 combo extension reverb amp with the A0-44 (which I will document on it's own thread later).

To be clear to Hammond lovers out there, these organs were all saved from being thrown out and are rougher than they look. I love Hammonds too, and I plan to reuse as much as possible myself and then put parts I'm not using into the hands of the people that need them to keep survivors going. Anything left over after that will be made into some fun art projects, but NONE of them will be wasted! I intend to take these nearly tossed parts and make them into something interesting and innovative, while saving a couple of old units that may need hard to find parts. So no need for this to upset anyone.

If you see any parts in the pics you need (stuff that I'm not talking about using, of course) just let me know! Full plans for my "Holy Roller" amp will be revealed here soon...

IMG_6902 Large.jpeg
 
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