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Hoffman Amps Forum image Author Topic: Question about adding power amp in jack to Bogen  (Read 2411 times)

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Offline ammscray

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Question about adding power amp in jack to Bogen
« on: May 19, 2015, 11:00:50 am »
Hi I lurk here all the time but this is my first post thanks for looking!

I have a bogen 35 watt challenger that I use to power a leslie 147, but sometimes its too hot so I wanna be able to bypass the preamp when I dont need jon lord all the time :)

I also wanna rewire the master volume from its usless position and put it in front of the PI so I have the control like it was a leslie amp

so the question is, do I take the signal at pin 6 of V2B, then go into a new coupling cap say .022, then to a shorting jack, then into the master volume, then into the junction of the .01/330 ohm?

Or, do I simply take the output from the .01 cap at pin 6 of V3 into the jack, then the master volume, then directly to the grid of V3?

Any suggestions/corrections are greatly appreciated!






Offline sluckey

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Re: Question about adding power amp in jack to Bogen
« Reply #1 on: May 19, 2015, 12:08:47 pm »
You need to think of V2B as part of the power amp. Here's what I'd do...
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline ammscray

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Re: Question about adding power amp in jack to Bogen
« Reply #2 on: May 19, 2015, 01:37:24 pm »
thanks Sluckey!

That raises another question then...b/c I was considering originally to insert the jack right BEFORE where the master is stock, to preserve the tone controls...would be nice to have them

 since I would be using 1/2 of V2 anyway if I do it your way, how much away from a power amp would it be if I did the above and used all of V2 and the tone controls?

a leslie 147 amp just has a 10K volume pot going into a 12AU7 as a PI into the two 6550s

thanks again

Offline sluckey

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Re: Question about adding power amp in jack to Bogen
« Reply #3 on: May 19, 2015, 02:04:03 pm »
You already have that capability. Just plug into the aux input.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline ammscray

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Re: Question about adding power amp in jack to Bogen
« Reply #4 on: May 28, 2015, 02:44:48 pm »
sorry man I had to go into the hospital....will try your suggestions as soon as I'm able
thank you

Offline PRR

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Re: Question about adding power amp in jack to Bogen
« Reply #5 on: May 28, 2015, 10:41:40 pm »
> I had to go into the hospital....

Glad you got out.

(I was in and out last year. Got stab-marks but they are not even impressive.)

 


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