add TMB tone stack to Brown Note Foxy 18

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rstoeck
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add TMB tone stack to Brown Note Foxy 18

Post by rstoeck »

Hi all,

I've successfully built a Marshall-style 18-watt amp whose sound I love (and only minor hum about on par with my factory tube amps)(thanks to Phil Zaphod and JMPGuitars for the layout). I would now like to try a more Vox-style amp and am intrigued by the Brown Note Foxy 18. But I am wondering about replacing the single tone knob with a TMB tone stack. I've found Rob Robinette's tone stack at https://robrobinette.com/images/Guitar/ ... n_Pots.pdf but I'm skeptical. Is it really as easy as just connecting the ground/input/output of the TMB tone stack in place of the single tone pot? I'll bet not, eh?

Thanks in advance for any info.
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Bieworm
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Re: add TMB tone stack to Brown Note Foxy 18

Post by Bieworm »

Its actually pretty easy, but know that you're noteably going to lose gain. Normally one would want to add an extra triode to recover the lost gain.
I'm not an expert, but connecting the tone stack to the cathode instead of the plate would avoid that loss, but the tmb tone controls will act differently at the cathode.
You've got to ask the right people or do a lot of research on Merlin Blencowe's documents.
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rstoeck
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Re: add TMB tone stack to Brown Note Foxy 18

Post by rstoeck »

Thanks! I did some of that and other reading and get your point.
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