Josh's Tremolo TMB Xtra Reverb

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Re: Josh's Tremolo TMB Xtra Reverb

Post by JMPGuitars »

Bieworm wrote: ↑
Sat 04/23/22 10:08 am
Holy Bible, Josh! I'm too drunk to be able to dial that amp in... too many knobs!πŸ˜€
Yeah, 1 more than yours. πŸ˜‰πŸ˜‰πŸ˜‚πŸ˜‚πŸ˜‚
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Re: Josh's Tremolo TMB Xtra Reverb

Post by Bieworm »

JMPGuitars wrote: ↑
Sat 04/23/22 2:27 pm
Bieworm wrote: ↑
Sat 04/23/22 10:08 am
Holy Bible, Josh! I'm too drunk to be able to dial that amp in... too many knobs!πŸ˜€
Yeah, 1 more than yours. πŸ˜‰πŸ˜‰πŸ˜‚πŸ˜‚πŸ˜‚
TouchΓ© πŸ˜‰ .. you do have more switches. OTOH, you're a switchy dude πŸ˜€
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Re: Josh's Tremolo TMB Xtra Reverb

Post by JMPGuitars »

I finally got around to test the voltages, and this amp sounds awesome! The tremolo sounds fantastic too. I have to fix an oscillation issue at the reverb tube. Because if its odd location, the wires are a little long, and I'm guessing the plate should probably be shielded. I might try moving the cathode wires first since that's easier. Next time I do something weird like this, I'll probably keep the tubes in order.

Here's a funny thing I caught when first testing the voltages. A couple wires in my PI were reversed. Normally I highlighter test before powering up, but this time I didn't. This is why we highlighter test, and why we take voltages. The voltages made it very clear the socket was wired wrong when 1 plate was HALF the voltage of the other. Awake me was able to fix tired me's mistake quickly.

I'll post photos and a demo after I sort out the reverb tube oscillation.

Thanks,
Josh
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Re: Josh's Tremolo TMB Xtra Reverb

Post by Bieworm »

JMPGuitars wrote: ↑
Wed 05/04/22 9:12 am
I finally got around to test the voltages, and this amp sounds awesome! The tremolo sounds fantastic too. I have to fix an oscillation issue at the reverb tube. Because if its odd location, the wires are a little long, and I'm guessing the plate should probably be shielded. I might try moving the cathode wires first since that's easier. Next time I do something weird like this, I'll probably keep the tubes in order.

Here's a funny thing I caught when first testing the voltages. A couple wires in my PI were reversed. Normally I highlighter test before powering up, but this time I didn't. This is why we highlighter test, and why we take voltages. The voltages made it very clear the socket was wired wrong when 1 plate was HALF the voltage of the other. Awake me was able to fix tired me's mistake quickly.

I'll post photos and a demo after I sort out the reverb tube oscillation.

Thanks,
Josh
I found out that the reverb circuit topology isn't to be underestimated. The way F#nd$r designed reverb topology inside his amps is very good and pretty problem free.. and that includes 2 tubes plus 2 RCA inputs plus transformer. The amps I built that way are really noisefree at reverb level, even when it's full on.
Screenshot_20220504-172819_Gallery.jpg
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Re: Josh's Tremolo TMB Xtra Reverb

Post by JMPGuitars »

Bieworm wrote: ↑
Wed 05/04/22 10:29 am
I found out that the reverb circuit topology isn't to be underestimated. The way F#nd$r designed reverb topology inside his amps is very good and pretty problem free.. and that includes 2 tubes plus 2 RCA inputs plus transformer. The amps I built that way are really noisefree at reverb level, even when it's full on.Screenshot_20220504-172819_Gallery.jpg
My board topology has certainly changed over time, but I don't think that's relevant here. I have long wires running parallel, and that's obviously a potential issue.
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Re: Josh's Tremolo TMB Xtra Reverb

Post by Bieworm »

Hey Josh... how about the little bugger? Ain't it operational yet?
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Re: Josh's Tremolo TMB Xtra Reverb

Post by JMPGuitars »

Bieworm wrote: ↑
Wed 06/08/22 2:44 pm
Hey Josh... how about the little bugger? Ain't it operational yet?
Yup, sounds cool too. The noise issue I had was that the 220K resistor for the reverb tank jack broke (broken lead snapped at the body). There's a minor issue that probably needs chopsticking, but I've been really busy with actual work. I'll post a demo once I have time to mess with it and play a little.

Thanks,
Josh
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