First sounds of the 18W TMB tremolo build

[Bieworm]

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.

https://www.dropbox.com/s/g6i9j0pbygiq1 ... 6.m4a?dl=0
Darn...

[JMPGuitars]

What happens when you tap the filter caps with a chopstick? If you get a loud pop or click noise, they're probably bad. But if that's not the case, they might need to be soldered better.

...and if that's not it, you might be searching for a cold solder joint somewhere else. That's my guess anyway.

[JMPGuitars]

BTW- I just updated the layout. It should make for a quieter / cleaner build.

[Bieworm]

BTW- I just updated the layout. It should make for a quieter / cleaner build.

looks nice!
yesterday I tried the 10k resistor to ground at the bifurcation of the normally 2x 470k from V2 pin 7. That was clean allright. But also the low disappeared and the amp sounded boxy like a f*nder champ
So I tried different values (220k and 100k)
The 220k was still little grindy, but much less than the 470k. The 100k was really clean, but also too thin.
Was thinking of putting a 500k pot to replace the resistor to ground. Are there remedies to bring back the low end across the pot or resistor? Would a parallel cap such as a .022uf be a 'cure'? In that case I would considder this the clean/drive knob. Maybe even make it footswitchable between the pot and another 470k resitor?

concerning the noise... tonight I will be rewiring the input jack. I had this kind of noise on my vibrolux and it turned out to be the connections on the input jack. Does that make sense, considdering the noise being there even with the preamp tubes removed?
Or what area should I be scanning for default?

For the filter cap tapping...I didn't get any weird noises doing that (I did this already before). But on my classic the .022 or the .01 cap coming from V2 (PI) pin 2 or 7 make a hollow amplified sound when popping them with a chopstick. I thought that was normal? Is that normal or should caps never make any sound?

And something strange happened to the voltages on the PI tube V3. Pin 1 has 219V which is ok, but pin 6 measures 202V. Is this a normal consequence of lowering the resistor to ground on pin 7 V2?

[Bieworm]

BTW- I just updated the layout. It should make for a quieter / cleaner build.

looks nice!
yesterday I tried the 10k resistor to ground at the bifurcation of the normally 2x 470k from V2 pin 7. That was clean allright. But also the low disappeared and the amp sounded boxy like a f*nder champ
So I tried different values (220k and 100k)
The 220k was still little grindy, but much less than the 470k. The 100k was really clean, but also too thin.
Was thinking of putting a 500k pot to replace the resistor to ground. Are there remedies to bring back the low end across the pot or resistor? Would a parallel cap such as a .022uf be a 'cure'? In that case I would considder this the clean/drive knob. Maybe even make it footswitchable between the pot and another 470k resitor?

concerning the noise... tonight I will be rewiring the input jack. I had this kind of noise on my vibrolux and it turned out to be the connections on the input jack. Does that make sense, considdering the noise being there even with the preamp tubes removed?
Or what area should I be scanning for default?

For the filter cap tapping...I didn't get any weird noises doing that (I did this already before). But on my classic the .022 or the .01 cap coming from V2 (PI) pin 2 or 7 make a hollow amplified sound when popping them with a chopstick. I thought that was normal? Is that normal or should caps never make any sound?

And something strange happened to the voltages on the PI tube V3. Pin 1 has 219V which is ok, but pin 6 measures 202V. Is this a normal consequence of lowering the resistor to ground on pin 7 V2?

[JMPGuitars]

Something else you could try, which I've done successfully in another similar circuit I designed...

You could do what I said before about adding the gain pot after the 470K/470K pair...and instead of just adding the gain knob, add both the gain (volume) and tone stack from the Lite 2b(ish) docs.

If you wanted to just replace the second resistor with a pot, I would still leave a minimum value resistor in place. Maybe a 250K pot in series with a 150K or 220K resistor.

Tapping caps on the signal line will likely give you a response depending on your position. Tapping filter caps (electrolytics) shouldn't give you any noise.

A bad connection on your input jack could cause similar noise. Does the noise go away with or without a guitar plugged in? However, I think you said that the noise was still there with the preamp tubes unplugged? If that's the case, you've already ruled out the preamp section, which includes the input jack.

Swap V1 and V3 and see what your voltages look like.

[Bieworm]

Something else you could try, which I've done successfully in another similar circuit I designed...

You could do what I said before about adding the gain pot after the 470K/470K pair...and instead of just adding the gain knob, add both the gain (volume) and tone stack from the Lite 2b(ish) docs.

If you wanted to just replace the second resistor with a pot, I would still leave a minimum value resistor in place. Maybe a 250K pot in series with a 150K or 220K resistor.

Tapping caps on the signal line will likely give you a response depending on your position. Tapping filter caps (electrolytics) shouldn't give you any noise.

A bad connection on your input jack could cause similar noise. Does the noise go away with or without a guitar plugged in? However, I think you said that the noise was still there with the preamp tubes unplugged? If that's the case, you've already ruled out the preamp section, which includes the input jack.

Swap V1 and V3 and see what your voltages look like.

The tube appeared to be with 1 pin next to the pingrabber , touching it, but not proper connected. So voltages ok after putting it correct.

Installed a 500k pot with 10k in series, connected to pin 7 V2, which also has the 470K to the board. This is a superb adjustment. Listen to the soundclip . I went from zero to all the way gradually.
The pot dimed with the 10k in series measured 480k...so big ok on that one
https://www.dropbox.com/s/zb1avxvofykqc ... 0.m4a?dl=0

[JMPGuitars]

Installed a 500k pot with 10k in series, connected to pin 7 V2, which also has the 470K to the board. This is a superb adjustment. Listen to the soundclip . I went from zero to all the way gradually.
The pot dimed with the 10k in series measured 480k...so big ok on that one
https://www.dropbox.com/s/zb1avxvofykqc ... 0.m4a?dl=0

That sounds great. Do you have a 100pF or 200pF cap you can put in parallel across the 470K resistor?

[Bieworm]

Installed a 500k pot with 10k in series, connected to pin 7 V2, which also has the 470K to the board. This is a superb adjustment. Listen to the soundclip . I went from zero to all the way gradually.
The pot dimed with the 10k in series measured 480k...so big ok on that one
https://www.dropbox.com/s/zb1avxvofykqc ... 0.m4a?dl=0

That sounds great. Do you have a 100pF or 200pF cap you can put in parallel across the 470K resistor?

I have got a 180pf ceramic..it's a very little cap. Is that allright? What's it do? Not making it brighter I hope... I have the treble pot on zero because the amp is very bright already

[JMPGuitars]

Installed a 500k pot with 10k in series, connected to pin 7 V2, which also has the 470K to the board. This is a superb adjustment. Listen to the soundclip . I went from zero to all the way gradually.
The pot dimed with the 10k in series measured 480k...so big ok on that one
https://www.dropbox.com/s/zb1avxvofykqc ... 0.m4a?dl=0

That sounds great. Do you have a 100pF or 200pF cap you can put in parallel across the 470K resistor?

I have got a 180pf ceramic..it's a very little cap. Is that allright? What's it do? Not making it brighter I hope... I have the treble pot on zero because the amp is very bright already

Ha, never mind then. What speaker are you using?

[Bieworm]

That sounds great. Do you have a 100pF or 200pF cap you can put in parallel across the 470K resistor?

I have got a 180pf ceramic..it's a very little cap. Is that allright? What's it do? Not making it brighter I hope... I have the treble pot on zero because the amp is very bright already

Ha, never mind then. What speaker are you using?

Ah...ok
It's a 2x10 jensen C10Q pair. They're in an old fender combo cab... plainly to try the amp
I'm still deciding the speakers for the endproduct. Probably 2x10 with emi 1028K 20 watts. Those are really great and smooth sounding . Bought the pair for 50€ a wile back. They come from a Dr Z 4x10 cab...

BTW that's a jaguar you're hearing

[JMPGuitars]

It's a 2x10 jensen C10Q pair. They're in an old fender combo cab... plainly to try the amp
I'm still deciding the speakers for the endproduct. Probably 2x10 with emi 1028K 20 watts. Those are really great and smooth sounding . Bought the pair for 50€ a wile back. They come from a Dr Z 4x10 cab...

BTW that's a jaguar you're hearing

That makes sense. I'm sure those Jensens are too bright. Like painfully bright. Judging by the tone curve, I'm guessing those 1028Ks should sound pretty nice, especially to tame the brightness.

[Bieworm]

It's a 2x10 jensen C10Q pair. They're in an old fender combo cab... plainly to try the amp
I'm still deciding the speakers for the endproduct. Probably 2x10 with emi 1028K 20 watts. Those are really great and smooth sounding . Bought the pair for 50€ a wile back. They come from a Dr Z 4x10 cab...

BTW that's a jaguar you're hearing

That makes sense. I'm sure those Jensens are too bright. Like painfully bright. Judging by the tone curve, I'm guessing those 1028Ks should sound pretty nice, especially to tame the brightness.

I think this amp is even bright enough for G12M's. But the dB on them is poor for this 18W
I think they would rock with g12 classic 80's. Bogner uses these in the EL34 shiva

[JMPGuitars]

I think this amp is even bright enough for G12M's. But the dB on them is poor for this 18W
I think they would rock with g12 classic 80's. Bogner uses these in the EL34 shiva

There's a lot of G12M Greenback clones that are more efficient to give you that extra headroom. But personally, I would probably pair a WGS BlackHawk with a WGS Reaper HP. I'm likely going to use that same pair for a friend's amp. Right now I have the BlackHawk with an Invader 50 in my cab, but that might be too punchy if it's as bright as you say. Or perfect since it's higher mids in the Invader, but it's hard to tell until I eventually get around to building this version.

I'm also a big fan of the Eminence Alnico Red Fang 12" 16Ohm, but they don't make it anymore. It's similar to the WGS BlackHawk, so that's convenient.

[Bieworm]

I think this amp is even bright enough for G12M's. But the dB on them is poor for this 18W
I think they would rock with g12 classic 80's. Bogner uses these in the EL34 shiva

There's a lot of G12M Greenback clones that are more efficient to give you that extra headroom. But personally, I would probably pair a WGS BlackHawk with a WGS Reaper HP. I'm likely going to use that same pair for a friend's amp. Right now I have the BlackHawk with an Invader 50 in my cab, but that might be too punchy if it's as bright as you say. Or perfect since it's higher mids in the Invader, but it's hard to tell until I eventually get around to building this version.

I'm also a big fan of the Eminence Alnico Red Fang 12" 16Ohm, but they don't make it anymore. It's similar to the WGS BlackHawk, so that's convenient.

In the classic I have an early 70S G12H30...probably from an old marshall or Orange cab
That one is crazy nice

[zaphod_phil]

To me the Red Fang sounds a little too bright, almost ice-picky with EL84s.

I have one of those 1970s G12H30s too. An awesome speaker with a big, solid sound!

[Bieworm]

Cab's in progress. Going to put the classic in the new cab. It's going to be a 2x10 with knobs on the front a la matchless. I will build the TMB tremolo in the 1x12 cab from my classic. That way I can stack them and have access to both control panels...

15868907823535924483298150363968.jpg

[JMPGuitars]

Very nice. You'd probably be glad to know I built a board for my Tremolo TMB Reverb version.

Check it out: https://www.instagram.com/p/B--WxlkHZib/

It will be a while before I can build it, I have another amp to do before it. But I'm looking forward to hearing it.

[Bieworm]

Very nice. You'd probably be glad to know I built a board for my Tremolo TMB Reverb version.

Check it out: https://www.instagram.com/p/B--WxlkHZib/

It will be a while before I can build it, I have another amp to do before it. But I'm looking forward to hearing it.

Great!! I'm curious how yours is gonna turn out..
I wonder if you will also need the clean mod pot. Mine won't get clean until the resistor to ground on V2 pin7 is between 60 and 120k. So the 250k pot with 220l resistor wouldn't get me in the right ballpark.
I have a new board, new turrets, belton sockets, all resistors and caps + 22 AWG stranded clothwire on the way. The new board is longer than a standard 18W type. Gives me room for the components + the PR mod.

[JMPGuitars]

Great!! I'm curious how yours is gonna turn out..
I wonder if you will also need the clean mod pot. Mine won't get clean until the resistor to ground on V2 pin7 is between 60 and 120k. So the 250k pot with 220l resistor wouldn't get me in the right ballpark.
I have a new board, new turrets, belton sockets, all resistors and caps + 22 AWG stranded clothwire on the way. The new board is longer than a standard 18W type. Gives me room for the components + the PR mod.

I made the schematic for the version I'm building include the pot by default. I'm going to use an A500K pot to determine the minimum and maximum useful values, and then go from there. I'll add a resistor in for whatever minimum value sounds good to me. I'm guessing 47K, but I won't know until I've tested it.

If your wire isn't pre-tinned, and bonded, tin it first.

Make sure you download the latest docs before you build. Whatever they are that day.