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Hoffman Amps Forum image Author Topic: 5F6A Build  (Read 6817 times)

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Offline rvaughan

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5F6A Build
« on: April 18, 2023, 07:42:51 am »
Investigating doing a Bassman 5F6A build and want to incorporate a couple of the Robinette mods, adjustable bias and master volume.  I want to use a turret board instead of eyelet and was wondering where I could find the dimensions for eylet/turret spacing to compare the Robinette, Hoffman and standard Fender layouts.  I wanted to see what kind of room there is for bias and balanced bias pots.

Offline sluckey

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Re: 5F6A Build
« Reply #1 on: April 18, 2023, 08:52:33 am »
Hoffman's board is 10.5" x 3.125". Bias pot is on the board. The board is pretty full but there "may" be room to add a balance trim pot. His layout is quite different (in a good way) from the original.

Rob's board looks identical to the original.

If I was building this, I would use Hoffman's turret board and forget about bias balance. Cost $34 with turrets installed.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline acheld

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Re: 5F6A Build
« Reply #2 on: April 18, 2023, 10:11:43 am »
Quote
If I was building this, I would use Hoffman's turret board and forget about bias balance.

That's what I did, and it's a great amp.  Hoffman's layout is the right stuff.  No need to get complicated with this circuit.  It just works.

 


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