Snarling Dogs - Bootzilla Fuzz Section [schematic]

[bbhardoin]

This is my first time trying anything like this, and first post here, so correct me if anything seems iffy.

My bassist brother had a Snarling Dogs Bootzilla fuzz/wah laying around collecting dust, so I bought it off him to see if I could mod it. I looked around online, saw next to nothing on anything that wasn't the Mold Spore or Whine-oh, so I figured I had a duty to post this thing up.

From the Factory:

I liked the wah sound - the hi and mid range wah settings work pretty well on guitar. But I was mostly in this pedal trying to score some cheap fuzz.
It sounded terrible to start with - all the highs and mids are filtered down heavily. This pedal was obviously designed for one note, totally fuzzed basslines. But the actual breakup sounded pretty ok.

Teardown:

I started off by tearing it open, and checking out the guts:


The fuzz section is at the top of the board, wah at the bottom. The board and wires seem kinda cheap, but not horrible. Knobs and switches attach via those white connectors, so the board is pretty easy to get out of the housing, and knobs/switches would be super easy to replace.

MC1458N dual-op amp in the middle there.

The I got to work drawing up a schematic of the fuzz section.

This is the back of the board - image flipped horizontally so I could check back and forth between the pedal and the picture without having to keep rearranging components in my brain.


I ended up with this schematic. No guarantees that it's even close to correct (this is my first time doing this, any input would be appreciated) but it seems really straightforward. Also, given my lack of experience here, I wouldn't be surprised if this was actually some super common circuit that I didn't recognize because of the goofy layout of my schematic.
Ca and Ra are notated to match the labels assigned on the other side of the board.


Mods:
So the most obvious thing to me was that massive input cap - labeled 2A224K. That is 220 microF right?
Anyway, I went ahead and replaced it with a cap in the pico-farad range (I don't exactly remember what I threw in but it was between .5 and 5 pF) - and now it sounds awesome! Response is still a lot of rolled off treble, but still some note definition in the highs as it gets fuzzy. Breakup is quick, but I've got this pedal following a Damage Control Demonizer set to just a bit of drive with a decent amount of compression. I'll get a recording up in the next couple days.

Future work may be to replace those LEDs with some stacked silicon diodes for smoother breakup (I think, based on what I've read online?). I may also play with Ca9 to mess with the filtering around the fuzz a bit more.



So, anything else anyone wants to see/know about the pedal before I get a recording up? Any other thoughts on modding it? Anybody else played with one before?

[Blitz Krieg]

i don't see the images

[bbhardoin]

hmm. Can't figure out how to make my google photos public.
In the meantime, this link should take you to the three photos I tried to share.

https://goo.gl/photos/1nxxv7Vzp18SqBNQ6

[domdec314]

I don't know if this is much use to you but I had copied the circuit board in DipTrace about a year ago:

The original board was of such poor quality and condition (lifted pads and traces) that I ended up just making a new one. At some point I plan on rebuilding the wah without the fuzz section into a standard wah shell.

[bbhardoin]

So I also pulled Ca9, basically removing the initial low pass filter. The fuzz knob now has the cool side effect of becoming brighter as I add fuzz, but I really like the sound of it.
It sounds a little dry if I run guitar straight into it. But with a bit of tube preamp overdrive ahead of it, things get fun. I finally got time to record a little jam just now, so you can hear what this thing sounds like. I love the sound of it with a bit of reverb.

I'm basically rolling up the volume on my LTD-Hybrid400 as the recording goes along, so you can hear the fuzz progress on the "Low Freakuency" setting. This guitar has a treble roll off as the volume drops, so much of that rounded off sound is the guitar smoothing out. Single coil neck pickup. The second guitar that just comes chunking in is what the fuzz sounds like on "High Freakuency" LED clipping setting - a bit nasally in this recording with a heavy boost ahead of it, but with a cleaner input it sounds much less fizzy.

First recording, dry:

Same recording, with reverb:

[chicago_mike]

You have MY interest!

I have been thinking of buying one of these and never got the chance. Now I must build one!!

[bbhardoin]

Glad to help (or to have hurt your wallet? haha). I'm probably gonna keep tinkering with it, maybe try different diode combos and fiddle with cap values a bit more. I'll try to remember to post whatever I end up with.

[chicago_mike]

Would you be willing to take more gut shots?

I think I want to build the thing and mod it, both the wah and fuzz.

[bbhardoin]

Sorry it took a bit, but I've added a few more photos to that same album I'd posted above: https://goo.gl/photos/1nxxv7Vzp18SqBNQ6
If there's any bits in particular you're curious about, lemme know.

[XinkycrowX]

I am new to this forum and new to building as well but I'd like to ask some advice. my friend came to me with one of these pedals and asked me to help him fix it. it lights up for both wah and fuzz but theres no signal that comes through, it's totally quiet. I've gone over the board with an audio probe and can't find any cold joints and I redid the solder on the input/output jacks. do you think I need to replace the molex and/or the wires for those spots? I'd appreciate any guidance, thanks. also I think it's pretty rad you went and posted the layouts and boards on here, it's been very helpful.

[chicago_mike]

Ordered one of these off evilly....Might look to see what mods I can do...if needed..

[manelik]

Digging up an old thread, just got a bootzilla that I was told had the fuzz way too loud. It had signs of repairs on the eyes so I came to check if components were correct. Everything seems fine and I think the previous owner tought it was too loud just because indeed it is a loud fuzz.

Nevertheless, I found some details on the posts on this thread that I may as well correct for further visitors. The layout trace posted above has the opamp inverted. And the schematic is almost right, just the output cap is connected to the opamp output (it goes to the minus input on the schematic) and the volume control is wired as a voltage divider (the outut on the pot goes to the switch). And some cap values are wrongly interpreted (input polyester 224 is 220 nF, 102 ceramics are 1 nF, 1000 times less than the reported uF values on the schematic)