# Pyromania



## Chuck D. Bones (Mar 29, 2020)

Thorpy FX Fallout Cloud aka Pryocumulus.  It's basically a triangle Big Muff with Baxandall tone controls.  What a fantastic sound!  It's in need of some decoration and labels, but I'm having too much fun playing thru it right now.  Marshall knobs and case from Tayda, gold stomp switch & nut from BLMS, intense yellow LED from EG.  Highly recommended.


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## Barry (Mar 29, 2020)

Looks great, gold is the new black!


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## Gordo (Mar 29, 2020)

Are those clear switch washers?


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## Chuck D. Bones (Mar 29, 2020)

Yes, clear nylon.


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## cooder (Mar 29, 2020)

Spiffin'!


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## BurntFingers (Mar 29, 2020)

Annoyingly there's no schematic for it. Cool looking thing though. Isn't it a 4 knobber? What does the 5th pot do?


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## MightySmallElectrons (Mar 30, 2020)

How does it compare to the Blackout Musket?


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## Chuck D. Bones (Mar 30, 2020)

BurntFingers said:


> Annoyingly there's no schematic for it. Cool looking thing though. Isn't it a 4 knobber? What does the 5th pot do?


What?  You mean other Fallout Clouds only have 4 knobs?  

The Fallout Cloud's first three stages are identical to the Triangle in the Muffin Fuzz build docs, except the 50nF caps are replaced with the easier-to-get 47nF caps and the transistors are BC549C.  The last stage is altered to support the Baxandall tone controls.


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## Chuck D. Bones (Mar 30, 2020)

MightySmallElectrons said:


> How does it compare to the Blackout Musket?



Does not have the up-front boost stage of the Musket, but does have a version of the Musket's FOCUS knob (that's the 5th pot).  I traced the schematic
from the board, then added a few features.
2nd-stage diode switch: Si - none - MOSFET
3rd-stage diode switch: Si - none - LEDs 
With the switches down (Si) and the CONTOUR knob at zero, it's a stock Fallout Cloud.  Turning CONTOUR up reduces bass going into the 1st stage.
The Baxandall tone controls work great, completely different from the standard BMP tone control.


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## Gordo (Mar 30, 2020)

Very nicely done Chuck.  I like the air intakes by the power jack  

It's a design feature I've used myself.


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## Mourguitars (Mar 30, 2020)

Chuck D. Bones said:


> Does not have the up-front boost stage of the Musket, but does have a version of the Musket's FOCUS knob (that's the 5th pot).  I traced the schematic
> from the board, then added a few features.
> 2nd-stage diode switch: Si - none - MOSFET
> 3rd-stage diode switch: Si - none - LEDs
> ...



" I traced the schematic from the board, then added a few features "....always a CDB Style !

Ive been studying it like always....would using different color LEDS change the tone ?

You put the caps on the  one pot....? for us newbies

Anyways , Awesome  build, i like that Tayda orange color enclosure...it hides the P-Touch labels very well..makes them blend in

Mike


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## Chuck D. Bones (Mar 30, 2020)

Gordo said:


> Very nicely done Chuck.  I like the air intakes by the power jack
> 
> It's a design feature I've used myself.



Keeps the transistors from overheating.  
I'll plug or cover those holes with something...


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## Chuck D. Bones (Mar 30, 2020)

Mike,
I wanted to experiment with a BMP that had better tone controls and the Pyrocumulus was a perfect platform for that.  Changing the diodes was an obvious choice.  I tried Schottkys, but they didn't sound much different from the 1N4148s.  I also tried varying the bias on the 2nd stage, but it didn't do anything useful IMHO.

LEDs vs the 1N4148 silicon diodes makes a significant difference in the sound.  Less compression, fatter midrange.  I didn't try different colors.  My expectation is that there would be a volume change and not much of a tonal change going from red to green or blue.

I mounted the 2 capacitors on the pot because it was easy to do.  They are supported by their leads.  It's hard to see, but there is clear heatshrink covering the joint where the capacitors are soldered to one of the yellow wires and a larger piece of heatshrink tying the two yellow wires together.  I could have put the caps on the vero board, but decided to go this way instead.


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## Mourguitars (Mar 30, 2020)

Chuck D. Bones said:


> Mike,
> I wanted to experiment with a BMP that had better tone controls and the Pyrocumulus was a perfect platform for that.  Changing the diodes was an obvious choice.  I tried Schottkys, but they didn't sound much different from the 1N4148s.  I also tried varying the bias on the 2nd stage, but it didn't do anything useful IMHO.
> 
> LEDs vs the 1N4148 silicon diodes makes a significant difference in the sound.  Less compression, fatter midrange.  I didn't try different colors.  My expectation is that there would be a volume change and not much of a tonal change going from red to green or blue.
> ...



Gotcha !

You told me to use the Green LEDS in that LGSM and it made it very creamy ..very smooth. My last LGSM i used the reg diodes off the build sheet...but I'm going to most likely replace them with maybe a diffrent color LED...

Just wondering if maybe using a Green,Yellow, Blue, White LED make the Fuzz types a little more smoother like in the Mod you done, i did notice a difference from the Red to Green in the LGSM..i socketed those and experimented...Green won hands down


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## Chuck D. Bones (Mar 30, 2020)

It's possible there would be a tonal difference with different LEDs on the Pyro, I didn't try it.  The distortion stages don't have a huge amount of headroom and if the LED voltage gets too large, the transistor saturates, giving a completely different sound.  That's what happens when I put the toggle switches in the middle position.  There are Muff-type circuits, like the Raincoat, that have no diodes and use transistor saturation to make distortion.

FYI, green & yellow LEDs have pretty much the same Vf, so they will sound the same.  White LEDs are made from blue LEDs, so their Vf is the same.  Red LEDs have the lowest Vf of the visible LEDs and IR LEDs have even lower Vf.


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## Mourguitars (Mar 30, 2020)

Oh just like green M&M's..lol

Yea i had a chart that showed all that stuff of the LED's.....just can't find it at the moment


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## phi1 (Mar 30, 2020)

LED color for Clipping diodes
					

Working on a Parentheses V1 but this question could apply across the board.  This design calls for a Red diode.  I have a clear one.  How much will it matter?  Is red more or less of something over clear, or blue or green?  Or multi colors?  I really want to use what I have on hand but I could...



					forum.pedalpcb.com
				




Just discussing this the other day. Here is a chart I found online, pretty consistent with what I’ve seen in the past.


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## Chuck D. Bones (Mar 30, 2020)

Here's a better chart.  Vf depends on If.  LEDs use for clipping are run over a range of currents.  The peak LED current in my Pyro is under 0.5mA.  Same goes for the LGSM.  At 0.5mA, Vf is 1.62V for red, 1.78V for green.  Hard clippers, like the Angry Charlie can get up to about 4mA thru the LEDs.


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## Mourguitars (Mar 30, 2020)

Thanks for the chart !

Saved in a new folder this time....you da man CDB !


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## Nostradoomus (Mar 30, 2020)

No serenade no fire brigade!


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## Hexjibber (Mar 31, 2020)

Nice! I have a board for this that I ordered ages ago but haven't got round to building yet, I've built quite a few Muffs in the past, does this have anything that separates it from the crowd? The original sounds great in all the YouTube vids I've watched.


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## Chuck D. Bones (Mar 31, 2020)

No, these pix are not Photoshopped.  Those holes next to the power jack were letting some of the good sound escape, so I plugged 'em.  Using countersunk screws was The Wife's idea.  Two 1/4-20 x 1/2" CRES screws did the job.  





I don't know how many of you watched "The Young Ones" back in the '80s, but those screws remind me of the studs in Vyvyan's 4head.





I had to shorten one of the screws to clear the Vero board.


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## Chuck D. Bones (Mar 31, 2020)

Hexjibber said:


> Nice! I have a board for this that I ordered ages ago but haven't got round to building yet, I've built quite a few Muffs in the past, does this have anything that separates it from the crowd?



The tone controls, particularly the Bass control, do some good stuff.  And of course, my mods are the icing on the &%^#ing cake.


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## Gordo (Mar 31, 2020)

Counter weights to keep the nose down on fast riffs.


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## MightySmallElectrons (Mar 31, 2020)

it's making me crave a Reese's Cup!


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## music6000 (Apr 1, 2020)

Cool , Looks Great!!!!

I built 2 Zen/Dumkudo's around 4 years ago & Tossed up where the 3 way Toggle's should go.
I went with the Side mounts to start with, Didn't like it & mounted them on the Back.
If I ever sell, the User can pick where he wants them!
I used these Flat Rubber Bungs to seal out the Dust!


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## music6000 (Apr 1, 2020)

Chuck D. Bones said:


> No, these pix are not Photoshopped.  Those holes next to the power jack were letting some of the good sound escape, so I plugged 'em.  Using countersunk screws was The Wife's idea.  Two 1/4-20 x 1/2" CRES screws did the job.
> 
> View attachment 3732
> 
> ...


Does it sound a bit Top Heavy after this Mod?


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## Chuck D. Bones (Apr 1, 2020)

music6000 said:


> Cool , Looks Great!!!!
> 
> I built 2 Zen/Dumkudo's around 4 years ago & Tossed up where the 3 way Toggle's should go.
> I went with the Side mounts to start with, Didn't like it & mounted them on the Back.
> ...



Nice build!


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