Russian Big Muff mod problem

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better_information
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Russian Big Muff mod problem

Post by better_information »

I removed R4, R12, R16, (more distortion) and R19 (I'm still trying to change up the tone control to taste).

I added true bypass, a sort of tone control bypass (bypass-able C11. It sounds like mush bypassed, still playing around.) and a feedback loop (Q3 emitter to Q1 emitter) . I swear it was working until I put back in it's case. It's now not passing wet audio, bypass still works. The funny thing is the feedback loop still works. The tone and volume controls do nothing as well. All the transistors are getting voltage. Where should I start?

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http://www.premierguitar.com/Stream/Str ... Type=image
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nbabmf
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Re: Russian Big Muff mod problem

Post by nbabmf »

Did you get the input and output wires backwards on the switch? Check all the wires to make sure they are connected, as well. Russian Muffs are notorious for flimsy wiring. Last, check your work with the mods. In the future, I would recommend one mod at a time.
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Re: Russian Big Muff mod problem

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I am a worthless human. Last night, a wire came loose, which I incorrectly traced, and incorrectly identified as a ground. Issue resolved. Well, other than I still hate the sound of it.

But yes, I did one mod at a time.

I have a late 70' muff that I really like, so this thing just sat in a drawer for 4 years or so. I'm hoping to make something usable out of it. There's loads of shit to try, that's for sure.
Last edited by better_information on Wed Apr 28, 2010 11:49 pm, edited 2 times in total.
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Re: Russian Big Muff mod problem

Post by devnulljp »

better_information wrote:I swear it was working until I put back in it's case. It's now not passing wet audio, bypass still works. The funny thing is the feedback loop still works. The tone and volume controls do nothing as well. All the transistors are getting voltage. Where should I start?
Bad ground
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Re: Russian Big Muff mod problem

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Yep. It's working like a charm now.
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Re: Russian Big Muff mod problem

Post by nbabmf »

If you've already done the emitter resistor mods and want MORE... swap the diodes in the first feedback loop for germanium ones. I'll be a little quieter, but more crunchy and beastly.
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I love the smell of solder in the morning.

Successful dealings with: blooghost, starcastic, bronzetalon, theavondon, absent, jero, sevenSHARPnine, magiclawnchair, oldangelmidnight, and others that I can't remember lol
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