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Hoffman Amps Forum image Author Topic: Hoffman plexi 50 questions  (Read 1945 times)

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Offline Stuff4bikes

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Hoffman plexi 50 questions
« on: May 19, 2022, 09:35:36 pm »
The layout shows all the can caps grounded together.......
I am one of the few people who does not like can caps....
And I have dozens of 47uf 500v caps on hand.....
I am going to use a single 100uf and 4-47uf's in
A fender(ish) dog house alignment...underneath the amp though..

How far away do you keep the impedience selector switch from the filter caps...?
Should I ground all the caps together or A,B,C grounded together and D,E grounded seperate?
I ordered a faceplate from modulus and it will have 4 holes for the inputs, the layout only
Calls for 2.
Can I just parralel another input jack for each channel?

Offline EL34

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Re: Hoffman plexi 50 questions
« Reply #1 on: May 20, 2022, 07:15:17 am »
Ground diagram from the library page is here
https://el34world.com/charts/grounds.htm


Offline sluckey

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Re: Hoffman plexi 50 questions
« Reply #2 on: May 20, 2022, 08:15:52 am »
Can I just parralel another input jack for each channel?
The schematic shows how to wire dual input jacks.
Quote
How far away do you keep the impedience selector switch from the filter caps...?
Somewhere between 1/4" and 1/4 mile.
« Last Edit: May 20, 2022, 08:18:37 am by sluckey »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Online Williamblake

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Re: Hoffman plexi 50 questions
« Reply #3 on: May 20, 2022, 08:27:50 am »
Quote
How far away do you keep the impedience selector switch from the filter caps...?
Somewhere between 1/4" and 1/4 mile.
[/quote]
Just dont go metric.

Offline Stuff4bikes

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Re: Hoffman plexi 50 questions
« Reply #4 on: May 20, 2022, 08:54:42 am »
Thanks for all your help.

 


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