B&M Sola Sound - Fuzz Unit  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...
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SPeter
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Post by SPeter »

Hi All,
Nice guts and ridiculous price! Identical to Vox MKIII ToneBender:
https://cgi.ebay.com/ws/eBayISAPI.dll?V ... 0464153930
:)
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Electric Warrior
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Post by Electric Warrior »

that's not true. the Barnes and Mullins Fuzz is nearly identical to the Jumbo Tonebender. The MKIII is a different breed.
there's a whole lot of gut shots to be found at the D*A*M forum...

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Greg
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Post by Greg »

Electric Warrior wrote:that's not true. the Barnes and Mullins Fuzz is nearly identical to the Jumbo Tonebender.
Which is pretty much a Big Muff.

Yes the MKIII is very different.
culturejam wrote: We are equal opportunity exposure artists.

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rs
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Post by rs »

I have a colorsound supa-wah-fuzz-swell, and the fuzz board is identical, same layout.

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Post by Electric Warrior »

There's two or three different layouts for the jumbo circuit with vertical controls.

some have slightly different resistor values (39k instead of 33k and 10 instead of 8k2) and/or component types (ceramic caps vs. styroflex). What I believe to be the earlier units have tropical fish caps instead of the greenies.
The values of the ceramic/styro caps may vary as well, but it's hard to see in the pictures I found. I've seen styroflex caps with a 500pf color code. Others have the number 220 printed onto them (or is this the voltage rating?). The ceramics in the ebay pics are 470pF. Does anybody have some more data?
And I'm not quite sure about the small cap at lug 1 of the tone pot. is it supposed to be 0.003µF or 0.004µF?

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Post by sonicvi »

Electric Warrior wrote:There's two or three different layouts for the jumbo circuit with vertical controls.

some have slightly different resistor values (39k instead of 33k and 10 instead of 8k2) and/or component types (ceramic caps vs. styroflex). What I believe to be the earlier units have tropical fish caps instead of the greenies.
The values of the ceramic/styro caps may vary as well, but it's hard to see in the pictures I found. I've seen styroflex caps with a 500pf color code. Others have the number 220 printed onto them (or is this the voltage rating?). The ceramics in the ebay pics are 470pF. Does anybody have some more data?
And I'm not quite sure about the small cap at lug 1 of the tone pot. is it supposed to be 0.003µF or 0.004µF?
It's usually .0039uF and that's what the original schematic calls for. Sola Sound called the B&M circuit "Fuzz A" and it is identical to the Jumbo with the exception of a 220K resistor at the output. I'm not sure what the purpose of that resistor is as it reduces the volume quite a bit. The pots are usually either all log taper or log for the volume and sustain and linear for the tone. Everything else about this circuit is pretty much evident from the photos and the "Fuzz A/Jumbo Tone Bender" schematic on the web. I think everybody pretty much knows by now the Jumbo is the same circuit as the Big Muff with first pair of clipping diodes and post tone gain stage removed. Doesn't sound like much but they're pretty significant differences soundwise.

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Post by Electric Warrior »

sonicvi wrote:
Electric Warrior wrote:There's two or three different layouts for the jumbo circuit with vertical controls.

some have slightly different resistor values (39k instead of 33k and 10 instead of 8k2) and/or component types (ceramic caps vs. styroflex). What I believe to be the earlier units have tropical fish caps instead of the greenies.
The values of the ceramic/styro caps may vary as well, but it's hard to see in the pictures I found. I've seen styroflex caps with a 500pf color code. Others have the number 220 printed onto them (or is this the voltage rating?). The ceramics in the ebay pics are 470pF. Does anybody have some more data?
And I'm not quite sure about the small cap at lug 1 of the tone pot. is it supposed to be 0.003µF or 0.004µF?
It's usually .0039uF and that's what the original schematic calls for. Sola Sound called the B&M circuit "Fuzz A" and it is identical to the Jumbo with the exception of a 220K resistor at the output. I'm not sure what the purpose of that resistor is as it reduces the volume quite a bit. The pots are usually either all log taper or log for the volume and sustain and linear for the tone. Everything else about this circuit is pretty much evident from the photos and the "Fuzz A/Jumbo Tone Bender" schematic on the web. I think everybody pretty much knows by now the Jumbo is the same circuit as the Big Muff with first pair of clipping diodes and post tone gain stage removed. Doesn't sound like much but they're pretty significant differences soundwise.
right, it says "Fuzz A" on the schematic and on the trace side of the circuit board.
thanks a lot for your help!

this is where the B&M porn is: http://dam.10.forumer.com/viewtopic.php ... es+mullins

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Post by peps1 »

Anyone come across a PCB layout for the B&M Fuzz Unit/3rd party Jumbo Tonebenders? :hmmm:
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celadine
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Post by celadine »

http://www.generalguitargadgets.com/

all kinds of goodies there; look under "projects".

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Post by peps1 »

Going the DIY route :D

Anyone happen to know the make and model of POTs, so I can get the pin spacing to scale the board?

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Image

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Post by Scruffie »

peps1 wrote:Going the DIY route :D

Anyone happen to know the make and model of POTs, so I can get the pin spacing to scale the board?
Aren't they the same Pots that EHX used? I think 24mm Pots have a fairly standardized pin spacing unless you use those other EHX ones with more spread out legs.

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Post by Electric Warrior »

They're Radiohms. No idea what happened with Radiohm, their products were available until recently. Replacements are available from Omeg amongst others..

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Post by sonicvi »

I used the right angle 16mm pots from Small bear in my clones and they just about fit the original spacing. I couldn't find the original type pots anywhere.
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Post by Electric Warrior »

Tyco/Citec makes Radiohm replacements as well..

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Post by peps1 »

mmmmmm......still finding variants in the pin spacing for the Tyco/Citec/Omeg Radiohm replacements (you got a model number for the 24mm Radiohm color sound used in this bad boy?)

Would be nice to drill the pot pads large enough to allow use of original, and 16mm Alpha pots :hmmm:
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Post by SPeter »

peps1 wrote:Going the DIY route :D

Anyone happen to know the make and model of POTs, so I can get the pin spacing to scale the board?

Image
Luckily I have some of these old pots!I realy love them! Pins(lugs) are 1mm wide and distance from lug 1 to lug 3 (center to center) is 10 mm!
:D

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Post by SPeter »

Scaled to the above mentioned distance(10 mm)!
Enjoy!
:D
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Post by Electric Warrior »

peps1 wrote:mmmmmm......still finding variants in the pin spacing for the Tyco/Citec/Omeg Radiohm replacements (you got a model number for the 24mm Radiohm color sound used in this bad boy?)

Would be nice to drill the pot pads large enough to allow use of original, and 16mm Alpha pots :hmmm:
I believe these are the right ones:
radiohm.png
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The Omegs are identical:

Image

So are the Citecs:
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Post by peps1 »

Electric Warrior wrote:
peps1 wrote: I believe these are the right ones:
Thanks Electric Warrior, with a 10mm pitch that fits in with SPeter...... sincerely thank you for taking the time to help! :D

Etched a test board, and found a couple of minor things i need to change to get it BANG ON authentic........ but will post with amended files tomorrow :D

Now the fun part of working out the component layout
Image

here is the photo im working from, incase anyone is handy with resister color codes and wants to help :wink:
Image
Image

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