Josh's 18W Tremolo TMB Builds

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Re: Josh's 18W Tremolo TMB Builds

Post by TriodeLuvr »

Bieworm wrote:
Mon 03/08/21 5:46 am

You have to know that the blackface style optocell tremolo is totally different from the bias vary tremolo. I hate the opto tremolo too.. I even converted the opto style of my vibro king to bias vary for that reason
Well, the amp in this thread doesn't use either method, right? It modulates the gain of the tremolo channel by varying the B+ on the preamp stage. That means there are actually at least three methods.

My first-ever commercial amplifier was a Guild Thunder 1 that I bought new around '65 or '66. It had bias tremolo, and I hated it. Whether that was due to the specific tremolo technique I'm not sure, but to me it was just a cheesy effect that no one except Tommy James would ever use. A very different sound than the clip Josh recorded.

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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

TriodeLuvr wrote:
Mon 03/08/21 1:26 pm
Bieworm wrote:
Mon 03/08/21 5:46 am

You have to know that the blackface style optocell tremolo is totally different from the bias vary tremolo. I hate the opto tremolo too.. I even converted the opto style of my vibro king to bias vary for that reason
Well, the amp in this thread doesn't use either method, right? It modulates the gain of the tremolo channel by varying the B+ on the preamp stage. That means there are actually at least three methods.

My first-ever commercial amplifier was a Guild Thunder 1 that I bought new around '65 or '66. It had bias tremolo, and I hated it. Whether that was due to the specific tremolo technique I'm not sure, but to me it was just a cheesy effect that no one except Tommy James would ever use. A very different sound than the clip Josh recorded.

Jack
No this amp wiggles the signal in the preamp stage. It's a very nice tremolo effect. Strong enough.
But the bias vary on my vibro king is a copy of the brown vibroverb. That is the best trem on the planet. When you play with lots of overdrive the tremolo effect mushes up the sound, but that 6G16 tremolo holds the sound together in a superior way, oozing and swamping in a way you think your speakers are gonna blow up. Niiiiiiice!!!
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

Josh, in the next clip please demo the reverb know with the extra caps switched on and off. Being a reverb-o-phile I'm really curious about that feature.
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Re: Josh's 18W Tremolo TMB Builds

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Bieworm wrote:
Mon 03/08/21 1:36 pm
TriodeLuvr wrote:
Mon 03/08/21 1:26 pm
Bieworm wrote:
Mon 03/08/21 5:46 am

You have to know that the blackface style optocell tremolo is totally different from the bias vary tremolo. I hate the opto tremolo too.. I even converted the opto style of my vibro king to bias vary for that reason
Well, the amp in this thread doesn't use either method, right? It modulates the gain of the tremolo channel by varying the B+ on the preamp stage. That means there are actually at least three methods.

My first-ever commercial amplifier was a Guild Thunder 1 that I bought new around '65 or '66. It had bias tremolo, and I hated it. Whether that was due to the specific tremolo technique I'm not sure, but to me it was just a cheesy effect that no one except Tommy James would ever use. A very different sound than the clip Josh recorded.

Jack
No this amp wiggles the signal in the preamp stage. It's a very nice tremolo effect. Strong enough.
But the bias vary on my vibro king is a copy of the brown vibroverb. That is the best trem on the planet. When you play with lots of overdrive the tremolo effect mushes up the sound, but that 6G16 tremolo holds the sound together in a superior way, oozing and swamping in a way you think your speakers are gonna blow up. Niiiiiiice!!!
The Thunder 1 was bias tremolo, but different in several ways. For one thing, there was no Intensity control. For another, I don't remember it being able to tremolo as slowly as the version in Josh's clip. Also, the 6G16 and Tremolo TMB appear to have more gain stages. That would change the tone quite a bit, especially when it's cranked. Maybe my negative impression of that amp's tremolo is the result of all these things together.

I'm already thinking that if I build another amp, it might be based on the Guild Thunder 1 RTV (reverb-tremolo) version. That also uses bias tremolo, but it includes an intensity control. Tone controls are based on the James bass/treble topology, not TMB. Most interesting to me is that it uses an entirely separate amplifier chain and speaker for reverb. I just happen to have two amplifier chassis from Hammond organs that do the same thing. Each chassis powers a pair of 7591 at 45-50W for the main channel, and a pair of 6GW8 at about 15W for the reverb-only output. I need to decide over the next few months whether to use these for a stereo pair (HI-FI) or two guitar amps. :D

Jack
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

TriodeLuvr wrote:
Mon 03/08/21 3:07 pm
The Thunder 1 was bias tremolo, but different in several ways. For one thing, there was no Intensity control. For another, I don't remember it being able to tremolo as slowly as the version in Josh's clip. Also, the 6G16 and Tremolo TMB appear to have more gain stages. That would change the tone quite a bit, especially when it's cranked. Maybe my negative impression of that amp's tremolo is the result of all these things together.
My trem goes that slow because I doubled the 1st capacitor to reduce the speed. There are different methods to achieve slower speeds with this circuit. Merlin covers at least 1 or 2 of them on his site. I'd suggest looking over his thoughts on tremolo if you're planning on doing something funky.
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Re: Josh's 18W Tremolo TMB Builds

Post by TriodeLuvr »

JMPGuitars wrote:
Mon 03/08/21 3:12 pm
TriodeLuvr wrote:
Mon 03/08/21 3:07 pm
The Thunder 1 was bias tremolo, but different in several ways. For one thing, there was no Intensity control. For another, I don't remember it being able to tremolo as slowly as the version in Josh's clip. Also, the 6G16 and Tremolo TMB appear to have more gain stages. That would change the tone quite a bit, especially when it's cranked. Maybe my negative impression of that amp's tremolo is the result of all these things together.
My trem goes that slow because I doubled the 1st capacitor to reduce the speed. There are different methods to achieve slower speeds with this circuit. Merlin covers at least 1 or 2 of them on his site. I'd suggest looking over his thoughts on tremolo if you're planning on doing something funky.
I'll review the articles at Valve Wizard. I'm pretty much done (and happy!) with this 36W as it stands. However, my next guitar project will be a tube-based vibrato for the effects loop. That will have a tremolo-type oscillator, and after hearing your clip, probably a switch to select between vibrato and tremolo. Thanks for the info!

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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

TriodeLuvr wrote:
Mon 03/08/21 3:44 pm
I'll review the articles at Valve Wizard. I'm pretty much done (and happy!) with this 36W as it stands. However, my next guitar project will be a tube-based vibrato for the effects loop. That will have a tremolo-type oscillator, and after hearing your clip, probably a switch to select between vibrato and tremolo. Thanks for the info!

Jack
It's funny because I'm pretty sure you mean it will switch between tremolo or tremolo. ;)
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Re: Josh's 18W Tremolo TMB Builds

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JMPGuitars wrote:
Mon 03/08/21 6:54 pm

It's funny because I'm pretty sure you mean it will switch between tremolo or tremolo. ;)
Sorry, forgot who I was talking to. I meant to say it will switch between tremolo and real tremolo. :lol: :lol:

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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

TriodeLuvr wrote:
Mon 03/08/21 8:39 pm
JMPGuitars wrote:
Mon 03/08/21 6:54 pm

It's funny because I'm pretty sure you mean it will switch between tremolo or tremolo. ;)
Sorry, forgot who I was talking to. I meant to say it will switch between tremolo and real tremolo. :lol: :lol:

Jack
lol, exactly! *real tremolo TBD ;) ;)
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

JMPGuitars wrote:
Tue 03/09/21 6:50 am
TriodeLuvr wrote:
Mon 03/08/21 8:39 pm
JMPGuitars wrote:
Mon 03/08/21 6:54 pm

It's funny because I'm pretty sure you mean it will switch between tremolo or tremolo. ;)
Sorry, forgot who I was talking to. I meant to say it will switch between tremolo and real tremolo. :lol: :lol:

Jack
lol, exactly! *real tremolo TBD ;) ;)
...and yank the guitar's vibrato along the line..
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Re: Josh's 18W Tremolo TMB Builds

Post by JMPGuitars »

Bieworm wrote:
Tue 03/09/21 11:25 am
...and yank the guitar's vibrato along the line..
Yeah, but you play a lot of F*nder guitars, so your vibrato thinks it's a tremolo. :lol: :lol:
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Re: Josh's 18W Tremolo TMB Builds

Post by Bieworm »

JMPGuitars wrote:
Tue 03/09/21 11:34 am
Bieworm wrote:
Tue 03/09/21 11:25 am
...and yank the guitar's vibrato along the line..
Yeah, but you play a lot of F*nder guitars, so your vibrato thinks it's a tremolo. :lol: :lol:
Naaahh. ..my offsets sport real* vibratos. Hope there aren't any lonely housewives reading here, gettin' crazy ideas 😃😃😃
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Re: Josh's 18W Tremolo TMB Builds

Post by TriodeLuvr »

LOL, didn't see that coming. :lol:
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Re: Josh's 18W Tremolo TMB Builds

Post by TriodeLuvr »

Seriously, I can't ever leave anything alone. What I really want (in one effects chassis) is a pitch-shifting tremolo driven by it's own LFO (low frequency oscillator), and a "standard" amplitude-shifting tremolo driven by a second LFO. I want the ability to control speed of the two independently, or to drive the two shifters simultaneously from one LFO, either in phase or out of phase with each other (selectable). That's not too much to ask, is it? :lol:

Also on this subject, if you were going to add standard tremolo to a non-tremolo Marshall using an effects loop, how would you implement it? Would you use a preamp tube as is done inside the Tremolo TMB? Would you consider an opto-coupler or some other method acceptable instead?

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Re: Josh's 18W Tremolo TMB Builds

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TriodeLuvr wrote:
Tue 03/09/21 2:12 pm
Seriously, I can't ever leave anything alone. What I really want (in one effects chassis) is a pitch-shifting tremolo driven by it's own LFO (low frequency oscillator), and a "standard" amplitude-shifting tremolo driven by a second LFO. I want the ability to control speed of the two independently, or to drive the two shifters simultaneously from one LFO, either in phase or out of phase with each other (selectable). That's not too much to ask, is it? :lol:

Also on this subject, if you were going to add standard tremolo to a non-tremolo Marshall using an effects loop, how would you implement it? Would you use a preamp tube as is done inside the Tremolo TMB? Would you consider an opto-coupler or some other method acceptable instead?

Jack
I'm pretty impressed by the tremolo of my imperial clone. It's an IRF840 mosfet doing the wiggle
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Re: Josh's 18W Tremolo TMB Builds

Post by dbharris »

TriodeLuvr wrote:
Tue 03/09/21 2:12 pm
Seriously, I can't ever leave anything alone. What I really want (in one effects chassis) is a pitch-shifting tremolo driven by it's own LFO (low frequency oscillator), and a "standard" amplitude-shifting tremolo driven by a second LFO. I want the ability to control speed of the two independently, or to drive the two shifters simultaneously from one LFO, either in phase or out of phase with each other (selectable). That's not too much to ask, is it? :lol:

Also on this subject, if you were going to add standard tremolo to a non-tremolo Marshall using an effects loop, how would you implement it? Would you use a preamp tube as is done inside the Tremolo TMB? Would you consider an opto-coupler or some other method acceptable instead?

Jack
Jack, have you looked at the Magnatone vibrato? I believe the varistors are the tricky part. But I understand there are some workarounds with modern parts

-Dan
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Re: Josh's 18W Tremolo TMB Builds

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I'm always disappointed with tremolo that's not part of the amp. Previous strymon flint owner talking here...
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Re: Josh's 18W Tremolo TMB Builds

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dbharris wrote:
Tue 03/09/21 8:34 pm

Jack, have you looked at the Magnatone vibrato? I believe the varistors are the tricky part. But I understand there are some workarounds with modern parts

-Dan
Dan, I spent a huge amount of time researching that about 10 years ago. I looked at data sheets for dozens and dozens of modern varistors, but couldn't find any that seemed correct. I even bought several types of silicon-carbide varistors from Russia. Based on the curves, some of them should have been close, but the actual measurements were all over the place. I still have 30 or 40 of those lying around somewhere. :cry:

In the end, I've decided it will make more sense to forget the varistor concept and develop something using Hammond saturable-core vibrato transformers (similar to the "Warbler"). I already have the transformers, so that's the first thing to try when I get back on this project.

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Re: Josh's 18W Tremolo TMB Builds

Post by TriodeLuvr »

Bieworm wrote:
Tue 03/09/21 10:49 pm
I'm always disappointed with tremolo that's not part of the amp. Previous strymon flint owner talking here...
I hope that doesn't turn out to be the case here. My initial thought on all this is to build an outboard tube version that's identical to Tremolo TMB or Fender tremolo. This isn't on the front burner right now due to several hi-fi projects that need my attention. It's a serious interest though, and I'll get to it eventually. :)

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Re: Josh's 18W Tremolo TMB Builds

Post by dbharris »

TriodeLuvr wrote:
Wed 03/10/21 4:38 am
dbharris wrote:
Tue 03/09/21 8:34 pm

Jack, have you looked at the Magnatone vibrato? I believe the varistors are the tricky part. But I understand there are some workarounds with modern parts

-Dan
Dan, I spent a huge amount of time researching that about 10 years ago. I looked at data sheets for dozens and dozens of modern varistors, but couldn't find any that seemed correct. I even bought several types of silicon-carbide varistors from Russia. Based on the curves, some of them should have been close, but the actual measurements were all over the place. I still have 30 or 40 of those lying around somewhere. :cry:

In the end, I've decided it will make more sense to forget the varistor concept and develop something using Hammond saturable-core vibrato transformers (similar to the "Warbler"). I already have the transformers, so that's the first thing to try when I get back on this project.

Jack
Yeah, I understand. If you still have any interest, this thread may be helpful.

http://ampgarage.com/forum/viewtopic.ph ... &start=105

I think I also have a PDF white paper sort of thing on my hard drive on the Maggie circuit, modern varistors that should work and the solution Martin Manning found. Let me know if you want me to send it to you.

I've thought I may build an active effects loop with built in reverb and Maggie style vibrato at some point. But it's a little beyond my abilities right now.

-Dan
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