Where to add tone control in Colorsound fuzz circuit?

[Chugs]

I built a Colorsound fuzz for my first build and I like it a lot. I want to add a tone control to the Colorsound. I have built a BMP tone control with a gain recovery stage from a vero layout I found here. My question is where is the best place to add the tone control to Colorsound fuzz circuit?

Due to my beginner status I tried what seemed the simplest way: The output of the Colorsound fuzz straight into the BMP tone control input and then the output from BMP tone control to the output jack. This works, but the tone control acts as a volume control as well; when you turn the turn control towards treble side you also get a lot more volume as well as treble and when you turn the tone control the other way you get less highs and a lot less volume.

Suggestions please?

[Derringer]

can you test the BMP tonestack+gain recovery outside the colorsound circuit?

if it behaves the same way, then there's probably a wiring error somewhere

if it behaves correctly then there's probably an error with how it was wired to the colorsound


do you have a schem of the colorsound to post?

[frequencycentral]

Do these two threads help?

http://www.diystompboxes.com/smfforum/index.php?topic=70498.0

http://www.diystompboxes.com/smfforum/index.php?topic=71050.0

[Chugs]

"can you test the BMP tonestack+gain recovery outside the colorsound circuit?"

I believe the tonestack is working fine but I will check it outside the Colorsound circuit to make sure.

"if it behaves correctly then there's probably an error with how it was wired to the colorsound"

Yes, I'm not sure how to wire it to the Colorsound so I am sure I got it wrong.

do you have a schem of the colorsound to post?

I used this layout for the fuzz...
http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/TUTORIALS/album21/COLORSOUND_ONE_KNOB_FUZZ.jpg.html

And this for the tonestack/recovery stage...
http://www.aronnelson.com/gallery/main.php/v/Cab42s-layouts/bmp_tonestack.jpg.html

[Chugs]

I read those two threads you posted Frequency Central before I did my post and they are indeed exactly what I am looking for. But being a clueless beginner I am still working out how schematics work.  I understand all the values and symbols but am still getting my head around the signal flow of a schematic.I think your schematic (the fuzz part of it) and the layout I used for the fuzz I built from are slightly different yes? (Links to my previous post for the layouts I used.)

PS. Your fuzz sounds great in your clip!

[Derringer]

couple more questions

1. Did your colorsound pedal work as per the layout you linked?

2. When you say that you hooked "the output of the Colorsound fuzz straight into the BMP tone control input and then the output from BMP tone control to the output jack" ... did you take the output from the 0.22 capacitor or did you take it from the middle lug of the 500K potentiometer?

3. Is all of this on one piece of vero?

[Chugs]

The Colorsound fuzz works fine on its own. The Colorsound and the BMP tone control are two separate builds. I took the output from the the 0.22 capacitor. (Also tried taking it form the middle lug of the 500K pot.)

I checked the BMP tone control on its own as you suggested Derringer and it looks like the problem lies there; on its own the BMP tone control acts as volume control. I have checked for solder bridges, checked the cathode on the electrolyte is towards ground and checked I have the wired the pot the right way and have correct component values on the board. (I used a 0.0047uf instead of a 0.004uf for C1) Any suggestions as what could be causing the tone control to act as volume pot?

[cpm]

the original fuzz has a lot of treble, so a simple series resistor and cap to ground may be enough for a tone control, cutting highs for a fatter sound

[Derringer]

The Colorsound fuzz works fine on its own. The Colorsound and the BMP tone control are two separate builds. I took the output from the the 0.22 capacitor. (Also tried taking it form the middle lug of the 500K pot.)

I checked the BMP tone control on its own as you suggested Derringer and it looks like the problem lies there; on its own the BMP tone control acts as volume control. I have checked for solder bridges, checked the cathode on the electrolyte is towards ground and checked I have the wired the pot the right way and have correct component values on the board. (I used a 0.0047uf instead of a 0.004uf for C1) Any suggestions as what could be causing the tone control to act as volume pot?

good, this means you're narrowing things down

Do you have the four track cuts in the proper places? Are they good cuts?
If you have a multimeter with a continuity checker (beeper) then this is a good place to use it.

If you don't have a multimeter, then a magnifying glass will help you get a better look.

It almost sounds like one of the tone pot's lugs is grounding out somewhere ... check those connections again ... if you have that multimeter, hook one end to the known ground and test other points and the pot lugs to see if you have connectivity to ground where you should not.

[Chugs]

Rechecked the cuts, they seemed fine to the naked eye but under the old magnifying glass one didn't appear to be quite as good as the others. Out came the craft knife, a little scratching and hey presto! It works!

Thanks for the help on that one Derringer. As a beginner I appreciate all the help I can get. Now that the tone control is working that brings me back to my original question: Where is the best place in the circuit to splice in the tone control?

I tried the following two configurations...

Taking the output off the wiper of the 500k volume pot of the Colorsound to the input of the BMP tone control and then from the output of the BMP to the output jack. This way works. There seems to be a little less output than before and there is a gradual loss of highs as you turn the volume down. Side effect of adding the tone circuit? Maybe changing the value of the output pot could compensate for this?

I also tried taking the signal from the output capacitor of the Colorosound through the BMP tone control and then back to the Lug 1 of 500K Volume of the Colorsound. (Lug 3 to ground, Lug two to output.) The volume control didn't work in that wiring configuration.

Any better way of doing this?

[Derringer]

awesome! glad to hear you're making progress!

and you're very welcome for the assistance ... I just like being able to give back to the forum in return for the guidance I have, and keep on, receiving

I would most likely do as you suggested and take the output from the 0.22 cap of the colorsound and run it directly into the  BMP tonestack+recovery and then the output of the recovery to Lug 3 of a 100KA pot (500 should still work), lug 2 out and lug 1 to ground
check your wiring in this configuration ... all grounds are connected?

if you have a 100KA pot ... try subbing that for the 500K and try it in both configurations ... see what happens

[frequencycentral]

I read those two threads you posted Frequency Central before I did my post and they are indeed exactly what I am looking for. But being a clueless beginner I am still working out how schematics work.  I understand all the values and symbols but am still getting my head around the signal flow of a schematic.I think your schematic (the fuzz part of it) and the layout I used for the fuzz I built from are slightly different yes? (Links to my previous post for the layouts I used.)

PS. Your fuzz sounds great in your clip!

I think my circuit is basically the same as yours, maybe just a few slight changes to resistor values here and there.

I would most likely do as you suggested and take the output from the 0.22 cap of the colorsound and run it directly into the  BMP tonestack+recovery and then the output of the recovery to Lug 3 of a 100KA pot (500 should still work), lug 2 out and lug 1 to ground

That's starting to sound almost exactly how my circuit ended up.

[Chugs]

I wired it up as you suggested Derringer and it works 100% now!  I think it sounds pretty similar to your build Rick. Thanks for the help once again guys. I've leant a few things and had fun. Next up on the experiment list is a gain control. Anyone tried adding a gain control?

[Derringer]

Fantastic man!

brings another smile to my face ... because just before I came back here to see what's going on, I finished soldering my new superfuzz layout, hooked it's leads to a breadboard and then to pots, powered it up, ran a sin through it into my scope and BAM ...nothing ?

damn breadboard gets me every time ... forgot to jumper the rails!

got that beautiful clipped double-frequency wave!


so where do you think you'll put the gain control? how are you going to implement it?

[frequencycentral]

Yes, good work! Glad it worked out for you. As for a gain control - compare the One Knob Fuzz with a Fuzz Face schematic. A Fuzz Face has a 1K pot instead of the fixed 1K resistor which is next to the 10uf cap in the layout you used. Its not quite as simple as just swapping the resistor for a pot, as you will also need to move the 10uf cap. See if you can figure it out - but do ask if you run into problems. Then you'll have basically a Fuzz Face with the BM tone stack. By the way - did you use a gain recovery transistor stage after the tonestack?

Fuzz Face: http://fuzzcentral.ssguitar.com/fuzzface.php

[Chugs]

I was thinking about an input gain of some sort but seeing how the fuzz only clean ups moderately well in response to changes of the guitar volume I didn't think that would work too well. I got a 1M pot and a couple of alligator clips and try connecting them to various parts of the circuit to see what the changes in resistance would do. I found that connecting the pot between the input cap and the base of Q2 acted quite well as a gain control. I got a little bit of crackle when turning the pot know which I guess is because, in effect, I am rebiasing the transistor?

I am glad your superfuzz is working Derringer. Got any soundclips?

I did use a gain recovery stage after the tone control Rick. Following your suggestion, and attempting to follow the Fuzz Face schematic you linked, I wired in a 1K pot in place of the 1K resistor with Lug 1 to ground.
I changed the orientation of the 10uf cap so the positive was to ground like in the Fuzz Face schematic and wired Lug two of the pot so it was on the same stripboard track as the negative leg of the cap. This didn't act as a gain control. I tried the same thing but with the 10uf cap after the jumper that links the track with the emitter of Q2 to the track with the 1K resistor but this didn't work either. I also tried the same two things but with orientation of the cap reversed but with the same result.

What am I doing wrong here?

Yes, good work! Glad it worked out for you. As for a gain control - compare the One Knob Fuzz with a Fuzz Face schematic. A Fuzz Face has a 1K pot instead of the fixed 1K resistor which is next to the 10uf cap in the layout you used. Its not quite as simple as just swapping the resistor for a pot, as you will also need to move the 10uf cap. See if you can figure it out - but do ask if you run into problems. Then you'll have basically a Fuzz Face with the BM tone stack.

[Derringer]

no clips yet ... still painting the enclosure

The original Fuzz Face had a positive ground and that's why the positive side of the cap went to ground.
Your fuzz has a negative ground, so you will need to put the negative side of the cap to ground.

So, in place of the original 1K resistor, you want to wire lug 3 of the 1K pot so that it connects directly to the emitter of Q2. Lug 1 Goes to ground. You want to then wire the capacitor so that the positive lead goes to lug 2 and the negative lead to ground. If I were doing this mod, I'd solder the capacitor directly to the pot (+lead to lug 2     -lead to lug 1).

[Chugs]

Yeah, I clicked about the positive/negative difference between the Fuzz face and Colorsound circuit after posting that message. I should have realised that straight away. Doh!

I tried what you suggest Derringer and it works fine and dandy. I see how that works now, its all clicked in my head. The positive/negative threw my thinking on a bit of an unnecessary tangent at first. I never would have thought of putting the capacitor on the pot lugs though. That is a good idea. Makes thing simpler.

I think I might be finished with this one now. The back of the veroboard is beginning to look a bit frazzled! It might be time to invest in a breadboard.

Thanks again for the help guys! Time to put down the soldering iron and pick up the guitar now!

[petemoore]

a simple series resistor and cap to ground may be enough
  That and some chosen values for the input/staging caps, perhaps even some LP filtering [light but permanent] earlier on.
  Notch filter though..depends on what you want your Fuzz to do.

[Derringer]

a simple series resistor and cap to ground may be enough
  That and some chosen values for the input/staging caps, perhaps even some LP filtering [light but permanent] earlier on.
  Notch filter though..depends on what you want your Fuzz to do.

depends on what you want your Fuzz to do < ---- and that's what it all comes down to!

Chugs ... CONGRATS MAN! Helluva hobby isn't it?

Yes .. buy a breadboard immediately. In fact ... buy three of them