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Hoffman Amps Forum image Author Topic: Hotswitch Mod - can I use a 3PDT to swicth out the master volume?  (Read 1809 times)

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Offline Gareth81

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Has anybody tried using the hotswitch mod with a 3PDT switch to disengage the master volume when normal gain is selected?
Any potential issues?


Many Thanks
Gareth

Offline pdf64

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Re: Hotswitch Mod - can I use a 3PDT to swicth out the master volume?
« Reply #1 on: January 04, 2021, 02:38:32 am »
From The Trainwreck Pages we can see 4 different basic types of master volume arrangements, which are you asking about?
But for any of them, turning them up full should, to all intents and purposes, take them out of circuit, and allow full gain. The loss caused by the master volume track load under such circumstances is somewhere between 0 and -1.5dB, ie negligible.
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Offline d95err

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Re: Hotswitch Mod - can I use a 3PDT to swicth out the master volume?
« Reply #2 on: January 04, 2021, 07:12:12 am »
Has anybody tried using the hotswitch mod with a 3PDT switch to disengage the master volume when normal gain is selected?
Any potential issues?

Please provide more info about what amp and mod you are talking about.

Offline Gareth81

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Re: Hotswitch Mod - can I use a 3PDT to swicth out the master volume?
« Reply #3 on: January 04, 2021, 09:22:19 pm »
Apologies, I am referring to Doug's hotswitch mod, in a 5f6-a circuit.


https://el34world.com/projects/hotswitch.htm

 


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