How do I make a passive volume box? It's for a one knob fuzz

[shipatsea]

I am assuming I can take a 250K pot and wire the input to one outer leg, the output comes out the middle and the other outer lug goes to ground. Sound right?

 

I am making a one knob fuzz and want to be able to keep it at around unity gain so I figured I could wire a pot after it to act like a master volume.

[IvIark]

Yep, input to lug 3, 2 to output and 1 to ground with this being the layout looking at the back of the pot:

 

[shipatsea]

cool thanks! And a 250k audio taper pot would be good?

[IvIark]

Any pot will work, but it will also create a high pass filter with the output capacitor of the previous pedal, so your selection will affect the overall brightness. Sometimes it's just a case of experimenting and choosing the one which sounds best to you.

[IvIark]

Just had a look at the Colorsound One Knob Fuzz schematic (if that's the one you're talking about), and the pot is volume. The level of dirt is preset with a fixed value resistor.

 

It's almost identical to the Meathead.

[shipatsea]

excellent info. Thanks for your help IvIark!

[kpd78]

Just had a look at the Colorsound One Knob Fuzz schematic (if that's the one you're talking about), and the pot is volume. The level of dirt is preset with a fixed value resistor. It's almost identical to the Meathead.

 

 

I had a Colorsound One Knob Fuzz, and the pot definitely increases gain/distortion/fuzz/whatever-you-want-to-call-it too...

 

the ones they sell now have a master volume trimpot inside.

[IvIark]

 

I had a Colorsound One Knob Fuzz, and the pot definitely increases gain/distortion/fuzz/whatever-you-want-to-call-it too... the ones they sell now have a master volume trimpot inside.

 

 

I'd be interested to see what the trimpot does because the one control on the original was a final attenuation which is a volume control. Any change to the level of fuzz is the same affect that a guitar's volume knob has on a fuzz pedal, so yes if you turn it down it tames the fuzz (and vice versa) but it's not the same as a fuzz control. If you were to put a passive volume control after the original one knob fuzz, then what you have is two volume controls, one feeding the other, with the second one basically acting as a fine tuner for the first.

 

I'd guess in the current ones they will have replaced the original control with a trimpot to set volume, and used the external pot as an overall fuzz control, replacing the 1K resistor. Which essentially gives you a Fuzz Face.

[kpd78]

this is how Colorsound describe it: "...with ONE control that did everything at the same time - gain , volume , nastiness , garaginess..."

 

When I had one, I used it in a TB loop with passive volume control - because it was stupidly loud.

All I know, is that turning the control up added loads more fuzz and changed the character a lot... doing exactly what Colorsound said it would.

 

I have seen 3 versions of the 1-Knob Fuzz; an early one with a very small circuit board (possibly the one you have the schematic for), the one I had (NO trimpot, but with a larger circuit board and higher parts count) and the current version (similar board but different layout) with the master volume trimpot.

[Reauchambeau]

I have a Colorsound Overdrive Boost that's way too loud, and I did what's been mentioned already, I added a volume pot to my TB loop pedal. works great.

[NITEFLY182]

I have yet to see a one-knob fuzz with a control that does anything beyond simple master volume. If you are hearing an alteration in tone as you turn it up, it's because the increased volume is changing the tone of gear after the pedal, or the physical experience of the pedal being loud is changing your perception of it.

[SonicVI]

I built one and there would be more highs as it got louder, but probably just because it was just louder. Another volume control after the pedal might just load it down and rekill the highs. You could try putting a small cap (250pF-ish) across the volume control to bypass some highs to the output.

[claytonjohn18]

I have yet to see a one-knob fuzz with a control that does anything beyond simple master volume. If you are hearing an alteration in tone as you turn it up, it's because the increased volume is changing the tone of gear after the pedal, or the physical experience of the pedal being loud is changing your perception of it.

 

 

This, especially if you amp is easily affected by boosted signals.

[kpd78]

 

This, especially if you amp is easily affected by boosted signals.

 

 

Even though I had effectively added a volume control to it?

(so turning it up DIDN'T increase the volume.)

 

Don't forget, Colorsound now sell them with a master volume control inside, so the circuit has probably been revised - probably several times knowing Colorsound - and no longer resembles the widely available schematic.

[IvIark]

Don't forget, Colorsound now sell them with a master volume control inside, so the circuit has probably been revised - probably several times knowing Colorsound - and no longer resembles the widely available schematic.

 

True, but if someone is making a DIY one up, then chances are he will be using the widely available schematic.

[kpd78]

True, but if someone is making a DIY one up, then chances are he will be using the widely available schematic.

it's also true that - prior to seeing the way this thread developed - I didn't know the schematic on the net was different to the Colorsound 1-Knob Fuzz I had.

[SonicVI]

I'm not sure, but I think the trimpot in the new CS pedal is a clean blend control, not master volume. As Nitefly pointed out, the old 1-knob volume control IS nothing but a volume control like you find in almost every other dirt pedal. It is not controlling the fuzz amount. If you are looking for less overall output and less low end you could use a smaller value for the volume pot, like 250K or 100K.