Jump to content

Super-simple Distortion/fuzz Schematic


Recommended Posts

I'm bored and I'm wondering if I can make something from the scrap parts I have lying around.

Theyre all from an old effects pedal I canibalised and theres a few parts I could salvage from a Hi-fi I dismantled.

I'm just looking for something really simple and easy to make- nothing fancy. Thats why I'm guessing distortion/ fuzz effects are my best bet.

I have:

  • 2 input/output jacks
  • 1 DPDT switch
  • LM358n chip (its a dual op-amp)
  • some random resistors
  • random assortment of capacitors
  • 1 meg pot
  • wire
  • 9V battery and clip
  • 2 diodes
  • a transistor of some description
  • a few other random parts from the hifi, like relays etc.

Best thing I've found so far is this: http://www.montagar.com/~PATJ/mufffuzz.gif

The 4558 thing in that circuit is also a dual op-amp so I'm wondering if I could just use the lm358 as a substitute

anybody know if I can just substitute the chips?

or know of any other possible simple circuits?


Link to comment
Share on other sites

I was just searching through the big hifi pcbs, checking to see if I have the parts to make the muff fuzz- and theres a 4558 chip on the board! :D

Looks like I have almost all the parts for the muff fuzz now!

(except theres a few cases where I'll need to use more than 1 cap/ resistor in series or parrallel to get the correct value)

I might just build the muff fuzz

I'll post the results if I do

Link to comment
Share on other sites

Almost any standard dual opamp will sub for another. People notice the most difference in sound between a BJT opamp (like a JRC4558) and a JFET opamp (like a TL072). You can see the differenc on a scope, too. The BJT type opamps clip a little harsher than the JFET types do. :D

Link to comment
Share on other sites

Thanks, I'll try both op amps and see which sounds best.

I have all the parts now except a few caps and resistors of the correct value. I could combine some to make equivalents- but I'm not totally sure that I dont already have what I need;

All the polarised caps are cylindical and have their value printed on them, but all the non polarised caps just have something like "102J" printed on them

How do I tell what value they are?

Google wasnt very helpful in helping me figure this out.

Link to comment
Share on other sites


Get a load of my makeshift 470K resistor- made from 8 small resistors in series :D

Link to comment
Share on other sites

The 102J (don't know what the J means) is trasnlated as follows.....caps are listed in picofarads (.000000000001 is 1 picofarad) and it is common for the values to be listed in 2 digit format. So, the 10 means 10 picofarads and the 2 means to the second power (or 2 decimal places to the left). So your cap is .000000001 or 1 nanofarad.

Google "reading capacitor values" for a good list if this doesn't make sense. One of the site that pop up will be worded so you can understand. No offense meant, but I know I can read something on one site and not understand at all and then read the same information, presented differently, on another site and the lightbulb appears above my head...Rog

Link to comment
Share on other sites

I'll look at the site, but I think I understood it when you described it.

It seems similar to the labeling resistors- maybe even simpler since it doesnt requre you to remember the colours.


I've nearly finished this thing already BTW- now I understand the caps I'll probably be done in about an hour or so. :D

Probably have to allow the usual 2 hours while I figure out why it wont work though :D

Link to comment
Share on other sites

Probably have to allow the usual 2 hours while I figure out why it wont work though laugh.gif

Looks like that might be the case :D

I've pretty much finished it- and I just tested it....

No sound :D


I've ommitted the 680k resistor between pin 3 and ground because I dont have one and couldnt be bothered to make another 8-resistor long chain right now B)

I'm intending to add the resistor later- I just fancied testing it. I was expecting at least *some* sound though...

  • could the missing resistor explain the silence?
    • Also I replaced the 100k pot with a 1 meg one. I know its not ideal, but between 1 and 0 the 1 meg pot should be pretty much identical to the 100k- right?

    [*]If I just remove the 1 meg pot , would a 100k resistor be equivalant to having it set permenantly to full volume?

    Merci beaucoup

Link to comment
Share on other sites

Finished it off.

I found out that the 9V battery I was using was dead :D Some fool had put a dead battery back in the pack (probably me actually)

Fingers crossed that it will work when I get a new 9V

Link to comment
Share on other sites

The J in 102J is the capacitor tolerance, which in this case is +/- 5%. When caps have a number printed like 102J the 10 is the pico farad amount less the multiplier however this cap size will be refered to as .001uF. A cap marked as 104 is 100,000pF but will be refered to as a .1uF or .1 micro farad. For very small amounts it typically will be printed like 560pF which is 560 pico farad.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...