Transformer Adapter Plate

From datc1NOSPA–(at)– Sat May 16 09:45:27 CDT 1998
From: “yes, another Tom”
Newsgroups: alt.guitar.amps
Subject: How to mount a larger Deluxe Reverb Power Transformer
Date: 16 May 1998 02:13:59 EDT
Xref: alt.guitar.amps:104978

If you wanna change the tranny in an amp without cutting or drilling, make
an adapter plate. Go down to your local scrap metal yard or source and find
a piece of 1/4″ aluminum plate about 4″ square or whatever. If you have to,
cut it or have it cut to size. On one side, drill out 4 holes in the
pattern of the stock trans footprint. Countersink these holes. Drill for
#8 hardware. On the other side, drill out the holes for the new trans and
countersink. Now, it is helpful to have countersunk screws with integral
lock washers, but those are hard to find. Anyway, you are gonna insert the
four screws to hold the new trans in place and put the plate on the chassis,
effectively sandwiching the screws between the chassis and the plate.
Install the other screws that conform to the original pattern and add nuts.
Install the new trans. You will have to drill holes for the wires (about
1/2″) before mounting the plate. This works with original type A mounting
(upright) and type B mounting (laydown), and is best suited for replacing
either type with a new type A. Since the type A is easiest to come by, this
system opens up more possibilities for you black tolex Fender types. It is
the same way racers adapt engines and trannies from different makers. It
works, and there are no added holes. It is more work, but the extra work is
the difference between someone who cares and a hack

Tom Crocker

To reply remove NOSPAM from address.

Rich Koerner wrote in message <6jj5ib$k5--(at)>…
>Gil Ayan wrote:
>> Still seems easier that cutting out the chassis for the new power
>> transformer…. 🙁
>You could try attaching endbells and standing it up. Then bolt holes
>are all you will have to deal with. Mine had a lot of iron, and to save
>chassis surface space I had to lay it down.
>> Agreed; the OT, however, is easier to relocate. But, you know the
>> PT craps out before the OT with the SS and the 6L6s. Easy to check,
>> voltages begin to brown out at around 30 watts at the output. I have
>> heard of people using old Deluxes OTs and getting 40 watts easily out
>> of them, with little distortion that is.
>Yes, that has been done. Beefing up the power supply will help get
>you there. Going to a Bandmaster OT will also help. However, the
>curve of the amp will change. To some, for the better.
>> >HEAVY output transformer was attached. I’ve popped two JBL K-120’s with
>> >it so far. An E-120 won’t fit with the fan in there. So I have to take
>> >easy on the single 12, and took out the KT-88s and use GE-6550As
>> >since.
>> My Deluxe has an 200 watt EVM 12L…
>Back when I did mine the EV-SRO was a little too heavy for my back then.
>Never could warm up to the sound of the EV speakers. Just a personal
>> Well, the most expensive part of the project would be getting a mill. 🙂
>> Really, it seems rather involved with the milling operation required.
>Try finding the endbells to fit the bolt pattern and winding size, to
>stand up your transformer of choice.
>Remember when you bolt them on to use the insulator washers too.
>> >Hope this helps.
>> Yes, it does, especially since it puts the effort required in
>> Thanks very much for the information.
>My Pleasure.
>Now, Go for it, and Have fun.
>Keep me posted on your progress.
>Rich Koerner,
>Time ELectronics.


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