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Hoffman Amps Forum image Author Topic: Question on Hoffman Deluxe Reverb build  (Read 2325 times)

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Offline Joeriz

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Question on Hoffman Deluxe Reverb build
« on: April 09, 2017, 06:28:40 pm »
Hello,

I am currently building a Hoffman Deluxe Reverb. In the instructions I received with the board from the Airtight Garage it says that one should either ground the green/yellow 6.3v center tap coming from the power transformer or use the 100 ohm resistors on the board...but not both. My question is: is there an advantage to one approach vs. the other?

Thanks,
Joe

Offline sluckey

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Re: Question on Hoffman Deluxe Reverb build
« Reply #1 on: April 09, 2017, 07:24:03 pm »
Flip a coin.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Joeriz

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Re: Question on Hoffman Deluxe Reverb build
« Reply #2 on: April 09, 2017, 09:13:51 pm »
I can do that.

Thanks!

Offline Joel

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Re: Question on Hoffman Deluxe Reverb build
« Reply #3 on: April 09, 2017, 09:51:38 pm »
As I undertand it, the 100 ohm resistors simulate a centre tap.  Useful when the 6.3Vac winding is not of the centre tap variety. 
The mouth of a happy man is filled with beer  - Egyptian Proverb

Offline pompeiisneaks

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Re: Question on Hoffman Deluxe Reverb build
« Reply #4 on: April 10, 2017, 04:32:20 pm »
Yeah as stated, the 100 ohms simulate a center tap, so you're wasting a few cents using them if you have a center tap.  On the other hand, if you want to go for almost 0 heater noise (so long as other things are done right) you can use a hum balance pot,  The center tapped transformer should be pretty perfectly balanced, BUT that doesn't mean it 100% is.  The hum balance pot allows dialing the hum to near 0.

~Phil
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Phil Davis
tUber Nerd =|D

Offline Tone Junkie

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Re: Question on Hoffman Deluxe Reverb build
« Reply #5 on: April 10, 2017, 07:11:41 pm »
+1 for humdinger.
Bill

 


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