smallsound/bigsound - Fuck Overdrive

[kwame]

I know a few people were interested so I took this to work with me last week. Sorry for the large pictures







I wanted to take it apart to get actual shots of the components and traces but it's pretty set on staying put.

[cdeschenes]

Thanks for the pictures.

Here is what I spy... Is there any way you can get some closer/clearer pictures of the board so we can get resistor values. Also if there is any way you can pull the PCB out to photograph the traces better Im sure that will help a lot more.

Smallsound/Bigsound Fuck Overdrive v1.3 2012

Diode:
1n4001
yellow LED

Capacitor:
220uF
10uF
10uF
10uF
10uF
10uF

Transistor:
2n5089
2n5X67
2n5089
2n5457
j201
j201

Pot:
Duel Gain Pot

Switches:
DPDT On-On
DPDT On-On
3PDT
SPST Momentary

[kwame]

I'll definitely try to take it apart again, but the solid core wiring along with the way he used the mounted pots make the board quite stable. Worse comes to worse I'm hoping better pictures will make it so that when I break this thing, I can put it back together or make another!

[Motter]

It says fuck in a number of languages on that silkscreen. We need more pics if not just for that reason.

[Motter]

One of those toggles ("light/heavy") looks like SPDT, not DPDT

[fakcior]

His polish translation of "fuck" is "pieprzyc" (under 2n5089). Very light translation though, haha

[cdeschenes]

One of those toggles ("light/heavy") looks like SPDT, not DPDT

Your right. I'll edit it. Thanks

[Nocentelli]

Despite reading about the "dynamically modulated sag feature", I can't help looking at the collection of separate transistors and jfets and thinking "several boosters strung in series": is the dual pot the gain control?

[Motter]

Despite reading about the "dynamically modulated sag feature", I can't help looking at the collection of separate transistors and jfets and thinking "several boosters strung in series": is the dual pot the gain control?

The manufacturer's manual says that the gain control affects two stages simultaneously, this is the ganged pot.

Also, the manual says that the other toggle (the DPDT, called "crackle") switches the operating mode of the momentary burst stomp. So that in one position of the crackle the pedal is in normal mode and the momentary switch puts it into "blown amp" mode, and in the other crackle position the normal state of the pedal is blown amp mode and the momentary puts it into normal mode.

There's also apparently a way to use an expression pedal to control the threshold knob, but the pedal in the OP doesn't seem to have that feature.

[cdeschenes]

Despite reading about the "dynamically modulated sag feature", I can't help looking at the collection of separate transistors and jfets and thinking "several boosters strung in series": is the dual pot the gain control?

The manufacturer's manual says that the gain control affects two stages simultaneously, this is the ganged pot.

Also, the manual says that the other toggle (the DPDT, called "crackle") switches the operating mode of the momentary burst stomp. So that in one position of the crackle the pedal is in normal mode and the momentary switch puts it into "blown amp" mode, and in the other crackle position the normal state of the pedal is blown amp mode and the momentary puts it into normal mode.

There's also apparently a way to use an expression pedal to control the threshold knob, but the pedal in the OP doesn't seem to have that feature.

I know this pedal have evolved some and one offs were made also. If we figure this out we might be able to make the Mini also by removing the crackle.

[jonasx26]

Hmm.. Looks like the yellow LED anode is connected to pin 5 of the TL072.
Bet its used for the offset-bias-trick used in many envelope-followers. Dr. Q etc..

[smallsnd/bigsnd]

Despite reading about the "dynamically modulated sag feature", I can't help looking at the collection of separate transistors and jfets and thinking "several boosters strung in series": is the dual pot the gain control?

the fuck is 3 jfet (2 j201, 1 2n5457) gain stages in series with the dual pot (gain) controlling the volume of the first 2. final 2n5089 is an emitter follower. SWTC for the high-cut control. the rest of the components are for an envelope follower aka the "dynamically modulated sag feature". it's modulating the voltage on the 2n5457 for the crackle and gnar gnar... i tried modulating each different stage, two at a time and all three but the particular stage was the best choice for a number of reasons.

Hmm.. Looks like the yellow LED anode is connected to pin 5 of the TL072.
Bet its used for the offset-bias-trick used in many envelope-followers. Dr. Q etc..

right you are.

I know this pedal have evolved some and one offs were made also. If we figure this out we might be able to make the Mini also by removing the crackle.

there are some other differences between the mini and the fuck since i wanted them to be different enough from each other to warrant the purchase of the two... larger coupling capacitors, bass cut, static bias (or starve) control. but yeah, get this and you'll essentially have the mini.

Also, the manual says that the other toggle (the DPDT, called "crackle") switches the operating mode of the momentary burst stomp. So that in one position of the crackle the pedal is in normal mode and the momentary switch puts it into "blown amp" mode, and in the other crackle position the normal state of the pedal is blown amp mode and the momentary puts it into normal mode.

There's also apparently a way to use an expression pedal to control the threshold knob, but the pedal in the OP doesn't seem to have that feature.

yeah. the dpdt switches the state of the momentary switch, so in one throw you have momentary on for crackle and the other throw you have momentary off for crackle. the momentary control seemed the most useful to me that way but i have made a handful for folks who wanted a latching switch - the dpdt is obviously unnecessary in that situation. the expression input just controls the resistance of the threshold knob - nothing fancy - i've probably only built a half-dozen with it included.

this is an older version of the pedal, by the way. the newer ones are vertically oriented and have the audio on one board and the envelope follower on another little daughterboard.

[juanro]

I really like this. Always wondered why there's so few "envelope -> control some parameter -> distortion" pedals.

Regards
Juanro

[Seiche]

Thanks brian, always great to have the manufacturer over giving clues! Doesn't happen very often anymore!

[kwame]

last of my pictures, again sorry for the size.

potentiometer values

[smallsnd/bigsnd]

you'll probably need to clip all of the wires if you want a proper trace since it's tracked on both sides.
either way, anyone can make something similar given the info i've provided - of course the devil is in the details.
also, in the newer version i use a 10kB threshold pot with a 10k trim in series to dial it in more precisely or to adjust for different pickup types) - works much better.

[Beedoola]

bump, did the owner get a chance to remove the PCB completely and attempt a trace?

[Beedoola]

bump. Anyone wanna trance theirs?

[maortojn]

resurrect-bump. Requesting audience with the almighty gods of circuit-tracing. This pedal is awesome and it's such a shame that it hasn't been traced.. Anyone wanna help? The thing i'm most interested in is the momentary sag control.

[smallsnd/bigsnd]

resurrect-bump. Requesting audience with the almighty gods of circuit-tracing. This pedal is awesome and it's such a shame that it hasn't been traced.. Anyone wanna help? The thing i'm most interested in is the momentary sag control.

any envelope control circuit will work and can allow you to further tailor a pedal to your particular liking.