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Hoffman Amps Forum image Author Topic: YAH* - Bogen K15 PA  (Read 3210 times)

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Offline DummyLoad

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YAH* - Bogen K15 PA
« on: March 19, 2011, 07:13:24 am »
* = Yet Another Hack. had it advertised on local craigslists and here on the forum, but no bites...

as usual donor amp is going to need PS attention, however, it does look like it was re-capped in the late 70's. in stock form the tone is dark and the tone control network does not impress. overall it's in fair to good cosmetic condition. a previous owner hacked a bunch of extra holes in the top of the chassis with dull bits so it's not very pretty - fortunately it's all hidden by the cover. cover is in decent shape, needs paint and comes complete with one user added 3/8" mystery hole...

of course, the ubiquitous grounded power cord will be installed.

tube compliment is: 2 x 12AX7; 1 x 6AV6; 2 x 6L6GB; 1 x 6AX5GT.

from my perspective, it is desirable to make use of as many of the tube holes as possible; looking through several fender plans, i settled on a mix of two fender pro tweed amps - the pre-amp of the 5E5A and the 5E5 cathode bias output stage.

for fender pro model voltages the PS looks like a good fit with solid state rectification in lieu of the 6AX5GT recto. the plan is to use the recto socket for tie points for the SSRs to minimize hacking. the presence control is to be rear mounted, and the first volume pot hole is to become an input jack hole.

schematic attached of proposed build.
« Last Edit: March 19, 2011, 08:56:13 pm by DummyLoad »

Offline PRR

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Re: YAH* - Bogen K15 PA
« Reply #1 on: March 19, 2011, 06:56:52 pm »
Presence pot probably does not go there.

Offline DummyLoad

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Re: YAH* - Bogen K15 PA
« Reply #2 on: March 19, 2011, 08:01:03 pm »
Presence pot probably does not go there.

did i miss something in the transposition?    :w2:


http://www.el34world.com/charts/Schematics/files/fender/pro_5e5a_schem.pdf

Offline DummyLoad

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Re: YAH* - Bogen K15 PA
« Reply #3 on: March 19, 2011, 08:56:41 pm »
Presence pot probably does not go there.

fixed - thanks!   :icon_biggrin:

 


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