Josh's 18W Tremolo TMB Builds

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JMPGuitars
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

Bieworm wrote:
Thu 10/08/20 10:21 pm
Can you define 'improved'? What makes it better?
You're supposed to try and figure out parts of that by looking at the images. I will say one thing, there are less tone-sucking resistors.
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Troubleshooting Basics:
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Step 3: Use a Voltage Chart from the downloads section to test your voltages.

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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

i love it! Josh,which "single tube reverb" are you referring to when you say yours is a better version? last time i googled it at least 3 or 4 versions came up!
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Fri 10/09/20 7:24 am
i love it! Josh,which "single tube reverb" are you referring to when you say yours is a better version? last time i googled it at least 3 or 4 versions came up!
Did you click on any of them? I'm pretty sure they're all referencing the same thing.
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Modern Ground Schemes
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Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

SW22R Schematic.png
anywhere near Josh?
there is less tone sucking resistors in this schematic than the others i looked at
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

The hardest thing to determine are the resistor values. Them Dales have no color code and the pics aren't hi res enough. Could be father time for me too 🤪
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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

Yeah I’m struggling to see those resistor values as well,most of the one tube circuits I looked at had a dwell pot which I can’t see on Josh’s and i’m trying to see if his is patched in series or parallel with the effects loop.
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

geoff 1965 wrote:
Fri 10/09/20 12:18 pm
Yeah I’m struggling to see those resistor values as well,most of the one tube circuits I looked at had a dwell pot which I can’t see on Josh’s and i’m trying to see if his is patched in series or parallel with the effects loop.
Series or parallel... I would do it parallel. But I also think it really doesn't matter. When in series my guess the reverb is best placed after the fx loop
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Fri 10/09/20 12:18 pm
Yeah I’m struggling to see those resistor values as well,most of the one tube circuits I looked at had a dwell pot which I can’t see on Josh’s and i’m trying to see if his is patched in series or parallel with the effects loop.
Bieworm wrote:
Fri 10/09/20 2:06 pm
Series or parallel... I would do it parallel. But I also think it really doesn't matter. When in series my guess the reverb is best placed after the fx loop
You're both wrong. ;)

Side note: if you look at the 1 tube schematics, you'll see the dwell knob can be replaced with a 1M to ground. Which I have. As does Bjorn's schematic for his Marble.

Thanks,
Josh
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

JMPGuitars wrote:
Fri 10/09/20 2:47 pm
geoff 1965 wrote:
Fri 10/09/20 12:18 pm
Yeah I’m struggling to see those resistor values as well,most of the one tube circuits I looked at had a dwell pot which I can’t see on Josh’s and i’m trying to see if his is patched in series or parallel with the effects loop.
Bieworm wrote:
Fri 10/09/20 2:06 pm
Series or parallel... I would do it parallel. But I also think it really doesn't matter. When in series my guess the reverb is best placed after the fx loop
You're both wrong. ;)

Side note: if you look at the 1 tube schematics, you'll see the dwell knob can be replaced with a 1M to ground. Which I have. As does Bjorn's schematic for his Marble.

Thanks,
Josh
Shoot.. you're right!! Come to think, the marble has the input for the verb circuit right after the tone stack and the output right before the PI. The imperial variant I'm building is laid out like that too. But it's dual channel, so there is dome more complexity to it..
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

Bieworm wrote:
Fri 10/09/20 2:56 pm
Shoot.. you're right!! Come to think, the marble has the input for the verb circuit right after the tone stack and the output right before the PI. The imperial variant I'm building is laid out like that too. But it's dual channel, so there is dome more complexity to it..
Getting warmer.

Side note: I drilled the box for the footswitch today: https://www.instagram.com/p/CGIrOKwnxSY/

Thanks,
Josh
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

Web Design: flashydragon.com
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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

I can’t find the marble schematic! can someone post it?
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

geoff 1965 wrote:
Fri 10/09/20 3:36 pm
I can’t find the marble schematic! can someone post it?
Josh found it... I never did. I copied the schematic from the amp in front of me. ( I have the marble)
This is what I have , but the first reverb tube uses just 1 triode.. well, send and recovery in the same tube in fact. I'm keeping the option open to double the send triode, so I'm doing it with 2 tubes in my build
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Fri 10/09/20 3:36 pm
I can’t find the marble schematic! can someone post it?
I was referring to Bjorn's schematic here: viewtopic.php?p=247256#p247256

Keep in mind he has some "wryte-o's" in it. But if you compare it to the single valve reverb, you can see it's almost the same with a few value changes. His schematic clues you into some of what I did if you pay attention to my photos in this thread (I had ZP's advice also - though he might not admit to having anything to do with a reverb circuit lol).

Thanks,
Josh
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

Web Design: flashydragon.com
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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

Bassman & reverb.gif
here's another example of a 1 tube reverb,this has unequal resistance/capacitance on the cathodes "we need to suss out what Josh and ZP used here!" and if you changed the 1M dwell pot to a 1M resistor to ground it's very similar.
Josh,what's your B+ going into the driver primary and the 2nd triode plate "pre resistor"?
you will have to excuse my ignorance at times as i have zero experience with any reverb circuit!
note: see how this patches in across the resistor into the phase inverter,well i have the same effects loop as Josh's in my 6V6 amp and could i patch the reverb across the same resistor as the FX loop?
7A87B3AF-3F66-43A1-8A41-EB98F5778CB3.jpeg
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Sat 10/10/20 9:30 am
Bassman & reverb.gif
here's another example of a 1 tube reverb,this has unequal resistance/capacitance on the cathodes "we need to suss out what Josh and ZP used here!" and if you changed the 1M dwell pot to a 1M resistor to ground it's very similar.
Josh,what's your B+ going into the driver primary and the 2nd triode plate "pre resistor"?
you will have to excuse my ignorance at times as i have zero experience with any reverb circuit!
note: see how this patches in across the resistor into the phase inverter,well i have the same effects loop as Josh's in my 6V6 amp and could i patch the reverb across the same resistor as the FX loop?
My cathodes are as drawn there, I didn't change them. My voltages are on the chart I posted in this thread.

You probably could get away with that, but that's not how I did it.
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

thank's Josh, the chassis on the 6V6 is the donor laney but i've bought a sheet of aluminium to make a new one and if i put the normal channel inputs vertical "standard" it gives me room for the extra reverb pot.
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Sat 10/10/20 10:30 am
thank's Josh, the chassis on the 6V6 is the donor laney but i've bought a sheet of aluminium to make a new one and if i put the normal channel inputs vertical "standard" it gives me room for the extra reverb pot.
Or just use a single input. How often do you benefit from having 2?
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

Web Design: flashydragon.com
Guitars / Amps / Effects: JMPGuitars.com
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Re: Josh's 18W Tremolo TMB Builds

Post by geoff 1965 »

Josh when you say your cathodes are as drawn do you mean the same as the last schematic or Bjorn's sketch?
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

geoff 1965 wrote:
Sat 10/10/20 11:05 am
Josh when you say your cathodes are as drawn do you mean the same as the last schematic or Bjorn's sketch?
The standard schematic you posted.
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'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright

Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info


Troubleshooting Basics:
Step 1: Remove and discard all JJ tubes.
Step 2: Highlighter test.
Step 3: Use a Voltage Chart from the downloads section to test your voltages.

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Re: Josh's 18W Tremolo TMB Builds

Post by ViperDoc »

(diligently waiting...)
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