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Hoffman Amps Forum image Author Topic: Has anyone tried a resistor or pot between the PS and G2 in a 5F1 amp ?  (Read 1903 times)

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Offline kagliostro

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Has anyone tried a resistor or pot between the PS and G2 in a 5F1 amp ?


(with the obvious purpose to reach early crunch effect)


Thanks


K
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Offline jjasilli

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  • Took the power supply test. . . got a B+
Yes, adding a screen resistor is a standard Champ upgrade.  See, e.g., my VibroChamp Schematic attached.  You can increase the value of the resistor for effect.


I'm suspicious of pots.  Another alternative is a SW to select between R values in pentode mode; maybe also add triode mode.   

Offline kagliostro

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Thanks JJasilli

which was your personal reason on adding this mod ?

Was the fact that is "good practice" to add a G2 resistor for G2 protection purpose

or you were looking for earlier compression effect ?

Thanks

Franco


p.s.: A rotary swith with multiple resistors ......... interesting idea
« Last Edit: April 28, 2015, 09:43:00 am by kagliostro »
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Offline jjasilli

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  • Took the power supply test. . . got a B+
I did it for "good practice", not for tone. 


BTW I tried the KOC mod of 2.2K screen resistors in an EL-84 amp, but didn't like it.  Tried some in-between values but didn't notice much difference. 

Offline kagliostro

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Thanks


Franco
The world is a nice place if there is health and there are friends

 


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