First sounds of the 18W TMB tremolo build

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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

JMPGuitars wrote:
Sat 04/04/20 8:50 am
Bieworm wrote:
Sat 04/04/20 8:29 am
Got some stuff on the way ...
BUT the only diodes and zeners I could get were:

UF5408
1N5359B

I'll have to try it with those
Those 24V Zeners are almost certainly too high. You want your Zener diodes to be around 2V higher than your cathode voltage. So somewhere in the vicinity of 14V. I recommended 15V in the docs, and I've seen people go as high as 16 and test well. You can try the 24V, but there's a good chance it won't work.

The UF5408 should be fine, that's supposed to be a higher wattage version of the UF4007 (1W vs 3W).

Thanks,
Josh
Right,now I remember .. bought those zenders to drop the B+. The were the lowest voltage 5 watters I could find.
Couldn't find the ones die the PR mod. Is there an alternative for zeners for the fizz? LED ?
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Sat 04/04/20 9:37 am
Right,now I remember .. bought those zenders to drop the B+. The were the lowest voltage 5 watters I could find.
Couldn't find the ones die the PR mod. Is there an alternative for zeners for the fizz? LED ?
5W is only for the voltage dropping. You can use 1W or probably even .5W for the Ruby Mod. 1N4744 is what I put in the schematic for that mod. Those are about 1W. Doesn't Mouser ship to you? They have outlets everywhere.
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Re: First sounds of the 18W TMB tremolo build

Post by zaphod_phil »

Bieworm wrote:
Fri 04/03/20 3:05 pm
JMPGuitars wrote:
Fri 04/03/20 3:00 pm

I think it would be much funnier if we sneaked into ZP's house and installed reverbs in all his amps while he's out.
...and rivet them amps closed ;)
How low! :lol: :lol: :lol:
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Re: First sounds of the 18W TMB tremolo build

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JMPGuitars wrote:
Sat 04/04/20 9:53 am
Bieworm wrote:
Sat 04/04/20 9:37 am
Right,now I remember .. bought those zenders to drop the B+. The were the lowest voltage 5 watters I could find.
Couldn't find the ones die the PR mod. Is there an alternative for zeners for the fizz? LED ?
5W is only for the voltage dropping. You can use 1W or probably even .5W for the Ruby Mod. 1N4744 is what I put in the schematic for that mod. Those are about 1W. Doesn't Mouser ship to you? They have outlets everywhere.
Some more crappy recordings with the TMB tremolo :
https://www.dropbox.com/s/sh56wppb87ti6 ... 3.m4a?dl=0
https://www.dropbox.com/s/m9q2woypzpc51 ... 4.m4a?dl=0
https://www.dropbox.com/s/m9q2woypzpc51 ... 4.m4a?dl=0
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

I really like the overall sound of your amp. In some parts it definitely sounds like you'll benefit from the Ruby mod.

Now, if you want to mess around a little more, let's try something out.

The 470K/470K attenuator going in to pin 2 of V2, let's move that away from the tube.
In between that and pin 2 let's add a couple things:

Put a 10K (or so) resistor back at pin 2 of V2.

Add a new knob for gain control, A1M. Connect pot pin 1 to the 470K/470K attenuator; connect pot pin 2 to the 10K resistor at pin 2 of V2 (using shielded cable only on this one); connect pot pin 3 to ground.

I'm guessing that will give you all the control you need.

If that works out for you, I'll either add that to the docs, or make a second version.

Thanks,
Josh
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

JMPGuitars wrote:
Sun 04/05/20 7:38 am
I really like the overall sound of your amp. In some parts it definitely sounds like you'll benefit from the Ruby mod.

Now, if you want to mess around a little more, let's try something out.

The 470K/470K attenuator going in to pin 2 of V2, let's move that away from the tube.
In between that and pin 2 let's add a couple things:

Put a 10K (or so) resistor back at pin 2 of V2.

Add a new knob for gain control, A1M. Connect pot pin 1 to the 470K/470K attenuator; connect pot pin 2 to the 10K resistor at pin 2 of V2 (using shielded cable only on this one); connect pot pin 3 to ground.

I'm guessing that will give you all the control you need.

If that works out for you, I'll either add that to the docs, or make a second version.

Thanks,
Josh

EDIT: I attached a schematic including the changes.
I like it big time too.
Going to perform the mod this evening and report back.
Thx

Edit: don't do it. It removed no grind, but only scooped off the highs and only dulled the sound to boring woolly and unrefined . Really not a progress. Not even worth recording. I changed it back. Anyway, Josh... it's just plain great as is. No need for tweaking, unless the PR mod.. otherwise it's really really great sounding. I think I will use it for a few rehearshals ( when quarantine is over!!!) and see from there. Apart from the fizz it's really good sounding. I am going to focus on the Ruby mod and building her home. Thx anyway
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Re: First sounds of the 18W TMB tremolo build

Post by zaphod_phil »

To bring back your highs and get rid of the dullness, I recommend placing a 100pF or 200pF treble bleed cap between pins 1 and 2 of the pot, as well as one across the series resistor in the 470K/470K attenuator pair.
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Re: First sounds of the 18W TMB tremolo build

Post by AussieTim »

Just had a listen to your sound clips and realised I need to get off my arse and finish my 18 watt project it has stalled for way too long, Ive realised this is what is missing in my life. Now that freedom work etc. is missing and I have time on my hands I am about to get busy with the soldering iron.
Tim
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Re: First sounds of the 18W TMB tremolo build

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AussieTim wrote:
Tue 04/07/20 8:02 pm
Just had a listen to your sound clips and realised I need to get off my arse and finish my 18 watt project it has stalled for way too long, Ive realised this is what is missing in my life. Now that freedom work etc. is missing and I have time on my hands I am about to get busy with the soldering iron.
Tim
start now! ;)
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

zaphod_phil wrote:
Tue 04/07/20 3:19 pm
To bring back your highs and get rid of the dullness, I recommend placing a 100pF or 200pF treble bleed cap between pins 1 and 2 of the pot, as well as one across the series resistor in the 470K/470K attenuator pair.
ZP... then there's still the OD from zero on the vol dial. I don't think that this mod's a solution.
Don't shoot, but I don't need heavy distortion anyway. I never use it and if I do there are good pedal on my board to move in that direction. I am satisfied when I have a light amount of drive at 3-4 on the vol dial. I aim for the breakup point on that setting. Now maybe...just maybe... an adjustable NFB loop would bring solace? If it could act like my classic 18W, but with TMB tone abilities. Wouldn't it be possible? And as an extra I have no need for the ruby mod, since the OD will never get into that area?
Any info on the values of caps, resistors and pot?
How about the JA TMB version 2.0 ?
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Tue 04/07/20 11:31 pm
ZP... then there's still the OD from zero on the vol dial. I don't think that this mod's a solution.
Don't shoot, but I don't need heavy distortion anyway. I never use it and if I do there are good pedal on my board to move in that direction. I am satisfied when I have a light amount of drive at 3-4 on the vol dial. I aim for the breakup point on that setting. Now maybe...just maybe... an adjustable NFB loop would bring solace? If it could act like my classic 18W, but with TMB tone abilities. Wouldn't it be possible? And as an extra I have no need for the ruby mod, since the OD will never get into that area?
Any info on the values of caps, resistors and pot?
How about the JA TMB version 2.0 ?
In theory this mod should reduce the gain, so maybe something else is wrong.

NFB is not the answer. It will kill the tone of the amp, and reduce the touch sensitivity.

Another option you have is to lower the second resistor (the one to ground) from the 470K/470K attenuator. You could try 330K or 220K and see what kind of results you get. If this reduces the gain, but you also feel you're lacking some of the highs, then do ZP's suggestion. Add a 100pF cap across the 470K series resistor.

You definitely need the Ruby Mod. I heard it in your demos. Installing the Ruby Mod could very well improve the way the amp works for you, and improve the distortion sound. Don't give up on it because it's hard for you to source (which it shouldn't be - you were looking at too high a wattage). Find a 1 watt 15V Zener diode. 16V or 14V would be fine too.
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Re: First sounds of the 18W TMB tremolo build

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JMPGuitars wrote:
Wed 04/08/20 6:19 am
Bieworm wrote:
Tue 04/07/20 11:31 pm
ZP... then there's still the OD from zero on the vol dial. I don't think that this mod's a solution.
Don't shoot, but I don't need heavy distortion anyway. I never use it and if I do there are good pedal on my board to move in that direction. I am satisfied when I have a light amount of drive at 3-4 on the vol dial. I aim for the breakup point on that setting. Now maybe...just maybe... an adjustable NFB loop would bring solace? If it could act like my classic 18W, but with TMB tone abilities. Wouldn't it be possible? And as an extra I have no need for the ruby mod, since the OD will never get into that area?
Any info on the values of caps, resistors and pot?
How about the JA TMB version 2.0 ?
In theory this mod should reduce the gain, so maybe something else is wrong.

NFB is not the answer. It will kill the tone of the amp, and reduce the touch sensitivity.

Another option you have is to lower the second resistor (the one to ground) from the 470K/470K attenuator. You could try 330K or 220K and see what kind of results you get. If this reduces the gain, but you also feel you're lacking some of the highs, then do ZP's suggestion. Add a 100pF cap across the 470K series resistor.

You definitely need the Ruby Mod. I heard it in your demos. Installing the Ruby Mod could very well improve the way the amp works for you, and improve the distortion sound. Don't give up on it because it's hard for you to source (which it shouldn't be - you were looking at too high a wattage). Find a 1 watt 15V Zener diode. 16V or 14V would be fine too.
I found a supplier. So will be ordering them 15V 1.3W zeners.
But all that tweaking has made the amp noisy..sh*t! I can not find the problem. Chopsticked and resoldered everything that I've been tweaking but no result. When I start playing the noise goes away and I think it stays away. But when I switch the amp off and little later back on ..The noise is there again.
I will order new and better turrets + all the board components again and redo it. But first I want to be tweaked out... so I can built a neat and new board without the perspective of soldering on and off after that.
I pulled the preamp tubes and the noise is there too. Must be a connection somewhere...
This is a very vague description and I realise it can have a ton of causes ...But anything comes to mind?
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Wed 04/08/20 6:38 am
I found a supplier. So will be ordering them 15V 1.3W zeners.
But all that tweaking has made the amp noisy..sh*t! I can not find the problem. Chopsticked and resoldered everything that I've been tweaking but no result. When I start playing the noise goes away and I think it stays away. But when I switch the amp off and little later back on ..The noise is there again.
I will order new and better turrets + all the board components again and redo it. But first I want to be tweaked out... so I can built a neat and new board without the perspective of soldering on and off after that.
I pulled the preamp tubes and the noise is there too. Must be a connection somewhere...
This is a very vague description and I realise it can have a ton of causes ...But anything comes to mind?
If you pulled the preamp tubes, and you still have the noise, then the noise isn't in the preamp.

When you rebuild, be sure to follow the latest layout (whatever that is at the time :wink:).

Post your current voltages, and a sample of the noise.
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

JMPGuitars wrote:
Wed 04/08/20 7:38 am
Bieworm wrote:
Wed 04/08/20 6:38 am
I found a supplier. So will be ordering them 15V 1.3W zeners.
But all that tweaking has made the amp noisy..sh*t! I can not find the problem. Chopsticked and resoldered everything that I've been tweaking but no result. When I start playing the noise goes away and I think it stays away. But when I switch the amp off and little later back on ..The noise is there again.
I will order new and better turrets + all the board components again and redo it. But first I want to be tweaked out... so I can built a neat and new board without the perspective of soldering on and off after that.
I pulled the preamp tubes and the noise is there too. Must be a connection somewhere...
This is a very vague description and I realise it can have a ton of causes ...But anything comes to mind?
If you pulled the preamp tubes, and you still have the noise, then the noise isn't in the preamp.

When you rebuild, be sure to follow the latest layout (whatever that is at the time :wink:).

Post your current voltages, and a sample of the noise.
I keep thinking it's the wire from V3 pin 2. Where it's connected to the .022 cap and 470k resistor I can hear noise when scratching with the chopstick. I already replaced that resistor tu rule that one out...
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Wed 04/08/20 12:13 pm
JMPGuitars wrote:
Wed 04/08/20 7:38 am
Post your current voltages, and a sample of the noise.
I keep thinking it's the wire from V3 pin 2. Where it's connected to the .022 cap and 470k resistor I can hear noise when scratching with the chopstick. I already replaced that resistor tu rule that one out...
That's because you're guessing. See my comment above. ;)
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

JMPGuitars wrote:
Wed 04/08/20 12:18 pm
Bieworm wrote:
Wed 04/08/20 12:13 pm
JMPGuitars wrote:
Wed 04/08/20 7:38 am
Post your current voltages, and a sample of the noise.
I keep thinking it's the wire from V3 pin 2. Where it's connected to the .022 cap and 470k resistor I can hear noise when scratching with the chopstick. I already replaced that resistor tu rule that one out...
That's because you're guessing. See my comment above. ;)
Josh I was right. I removed the cap, resistor and wire from the turret. Cleaned it from solder and rewired. Sounds way better. If it wasn't the cause of it, it sure didn't help. There were little pieces of wire leftovers in the solder I think. But it's way better now.

Even the pop when switching the amp off is gone...that was one effect of the malchanges too..
Last edited by Bieworm on Wed 04/08/20 1:41 pm, edited 1 time in total.
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

New voltage chart:
15863711773083414959812145982417.jpg
We'll see...
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Wed 04/08/20 1:28 pm
Josh I was right. I removed the cap, resistor and wire from the turret. Cleaned it from solder and rewired. Sounds way better. If it wasn't the cause of it, it sure didn't help. There were little pieces of wire leftovers in the solder I think. But it's way better now.
Well, that makes sense. You need to keep your connections clean. If you can get a proper desoldering gun, that will make your life easier. My soldering station has one built in, so I find it easy to rework things.

You could try your luck with some de-soldering braid, or a desoldering pump, but they take more effort with less ideal results.
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Re: First sounds of the 18W TMB tremolo build

Post by Bieworm »

JMPGuitars wrote:
Wed 04/08/20 1:55 pm
Bieworm wrote:
Wed 04/08/20 1:28 pm
Josh I was right. I removed the cap, resistor and wire from the turret. Cleaned it from solder and rewired. Sounds way better. If it wasn't the cause of it, it sure didn't help. There were little pieces of wire leftovers in the solder I think. But it's way better now.
Well, that makes sense. You need to keep your connections clean. If you can get a proper desoldering gun, that will make your life easier. My soldering station has one built in, so I find it easy to rework things.

You could try your luck with some de-soldering braid, or a desoldering pump, but they take more effort with less ideal results.
An amateur like me obviously has the pump ;)
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Re: First sounds of the 18W TMB tremolo build

Post by JMPGuitars »

Bieworm wrote:
Wed 04/08/20 2:39 pm
An amateur like me obviously has the pump ;)
lol, I don't miss those days. But try adding a drop of solder while you heat up the turret. That might help the pump do its job.
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