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Hoffman Amps Forum image Author Topic: 5f6a - 4 Filter Caps vs. Hoffman’s 5?  (Read 1977 times)

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Offline Mr. Mojo

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5f6a - 4 Filter Caps vs. Hoffman’s 5?
« on: March 24, 2020, 12:48:55 pm »
The original 5f6a had 4 filter caps in the dog house - but Hoffman’s design uses 5 - I searched, but could not find an explanation for this - can anyone tell me why?

Offline sluckey

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Re: 5f6a - 4 Filter Caps vs. Hoffman’s 5?
« Reply #1 on: March 24, 2020, 01:36:19 pm »
The original 5f6a had 4 filter caps in the dog house - but Hoffman’s design uses 5 - I searched, but could not find an explanation for this - can anyone tell me why?
Both amps have 5 filter caps. The original has 4 in the doghouse and 1 on the main board.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Mr. Mojo

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Re: 5f6a - 4 Filter Caps vs. Hoffman’s 5?
« Reply #2 on: March 24, 2020, 02:31:51 pm »
Gotcha!  I see what is going on -- the 5th Cap (#4) replaces the 8uF cap in the PreAmp Ground bus section on the Fender schematic.  That makes sense now.  Thank you!

Other question - - what does raising this value to 20uF do?

Offline 66Strat

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Re: 5f6a - 4 Filter Caps vs. Hoffman’s 5?
« Reply #3 on: March 24, 2020, 02:56:18 pm »
Other question - - what does raising this value to 20uF do?

It shunts to ground all of the magic mojo that make the 5F6-A Bassman the king of guitar amps and turns it into a lifeless tone turd. :laugh:

I seriously doubt that you could nhear any noticeable difference. It may help a little bit in filtering and reduce the potential for 120 hz hum.
« Last Edit: March 24, 2020, 03:06:07 pm by 66Strat »
Regards,
JT

 


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