The Most Expressive Wah I Have Played...

[Paul Marossy]

Someone recently sent me an original Colorsound inductor wah pedal to tweak. When I was testing it out, I noticed that it had a really big range in sounds due to the 2" of travel it has!

So I was able to work out a deal with the owner of this wah pedal to do a partial trade for my labor - for an empty Colorsound wah pedal shell that he had. I initially put my Colorsound inductorless circuit in it, but it just didn't excite me at all. Today I decided to build this inductor based circuit and put it in there instead. It's very similar to a CryBaby, but without a resistor in parallel with the inductor, a 100K input resistor and a 100K resistor/10uF cap to ground at the inductor instead of 68K resistor/4.7uF cap.

Aside from a very microphonic inductor which I have to replace, I must say that this is the most expressive wah pedal I have ever played. I think I like it as much as the Maestro Boomerang. It's a different sounding wah, but I like it just as much. It's real good at the "whacka-whacka" thing, too.

One other thing I thought I'd mention is that I really like how the shell is designed. The mechanism that turns the pot is very ingenious and effective. It also feels a lot smoother than the rack and pinion system found in other wah pedals. In any case, just thought I'd share... 

[RedHouse]

Post a pic?

[Nasse]

Years ago I had a friend who had such wah wah. One very clever former forumite send me pics of that mechanism years ago

I have thought that one thing that makes that mechanism work so good is it takes better advantage for full rotation angle of a potentiometer. I have very limited wah experience but those old cheap italians and japanese I saw did not make full travel. But with my friends Colorsound was such that you had to move your foot more, and that was not so nice feel action. I did some cardboard modellings and thought if you make the wah case and footrest longer perhaps you could get more "normal" feel to the colorsound mechanism. But I never managed to make some sawdust and diy plastic parts

And cant remember if it was workin opposite direction than my own wah

[Paul Marossy]

Years ago I had a friend who had such wah wah. One very clever former forumite send me pics of that mechanism years ago

I have thought that one thing that makes that mechanism work so good is it takes better advantage for full rotation angle of a potentiometer. I have very limited wah experience but those old cheap italians and japanese I saw did not make full travel. But with my friends Colorsound was such that you had to move your foot more, and that was not so nice feel action. I did some cardboard modellings and thought if you make the wah case and footrest longer perhaps you could get more "normal" feel to the colorsound mechanism. But I never managed to make some sawdust and diy plastic parts

And cant remember if it was workin opposite direction than my own wah

I think that is the key to it being so expressive - the more full pot rotation. The long throw does take some getting used to. I never liked the short throw on a CryBaby type wah - it's too short for my liking. I like the Maestro Boomerang in terms of length of throw, it has probably 1/2" more than the CryBaby does. And the Colorsound has even more than the Boomerang does. 

Post a pic?

I'll try to take a few pics of it tomorrow sometime.

PS - Here is the schematic: http://fuzzcentral.ssguitar.com/schematics/colorsoundwah.gif
I used a 2N5089 for Q1 and a 2N3904 for Q2.

[Paul Marossy]

Here's a few pictures:



You can kind of see the rubber isolators on the four corners of the circuitboard here
(installed to help with microphonic inductor syndrome)


Look at the amount of travel this thing has...  It's cool, though, because
it can go from a more traditional wah sound to an almost synthy sound in the lower range.


I tried to get some close up pictures of the mechanism that operates the pot, but I couldn't get any good shots, so I made a little video of it: http://www.diyguitarist.com/Misc/CSW-Mechanism.MOV

[tiges_ tendres]

I tried out a reissue coloursound a few years back.  The pedal throw was enormous!  It made me feel a bit seasick!

[DougH]

I must say, this thread and your clips of the Boomerang are starting to give me a hankerin' for building a wah.

[Paul Marossy]

I must say, this thread and your clips of the Boomerang are starting to give me a hankerin' for building a wah.

Just do it! 

I'm going to do a soundclip for this Colorsound wah pedal sometime in the next day or two, because hearing is believing. 

[R O Tiree]

It still only looks as though the pot is getting about 120 degrees of rotation in that video clip?

[Paul Marossy]

It still only looks as though the pot is getting about 120 degrees of rotation in that video clip?

I think it's more than that. It has a lot more range than a CryBaby does, so it's more than whatever the range is on a CryBaby.

[Gus]

I worked on one years ago.  I traced the plastic cam and measured resistance at differet parts of the sweep (wiper to each end two reading for 1/2, 1/3 etc)
  Now I can't find my tracing and readings.  If you still have the real wha you might want to do this to figure out the taper.  To do it 100% you would need to pull the pot and set it at different degrees and measure resistance to figure out the taper of the pot the total taper might be affected by the offset of the slot in the plastic piece that fits on the wha pot and the foot petal pin slides in.
i think there is something to the pot cam and foot petal and pot that makes the colorsounds inductor and inductorless whas sound good.

[Paul Marossy]

IIRC, a normal pot has a 270 degree rotation. So if something turns a pot thru 1/2 of its allowable rotation, that would be 135 degrees. Looking at the actual rotation of the pot shaft and not the plastic gizmo that turns it, I'm guessing that the Colorsound mechanism turns the pot more than 1/2 way thru its rotation, it's more like 180 actual degrees. That would make the throw more than 135 degrees, and more like 2/3 thru the allowable pot rotation. It's definitely way more than any other well known commercial wah pedal design I have seen.

[R O Tiree]

IIRC, a normal pot has a 270 degree rotation. So if something turns a pot thru 1/2 of its allowable rotation, that would be 135 degrees. Looking at the actual rotation of the pot shaft and not the plastic gizmo that turns it, I'm guessing that the Colorsound mechanism turns the pot more than 1/2 way thru its rotation, it's more like 180 actual degrees. That would make the throw more than 135 degrees, and more like 2/3 thru the allowable pot rotation. It's definitely way more than any other well known commercial wah pedal design I have seen.

Still looking like about 120 degrees and certainly not more than 1/2 travel on a 270 degree pot (although it could be 300)...



I took screen shots of the cam at the extremes of travel (top 2 pics), marked a red line along the lower edge of the cam, rotated the left pic so the bottom edge of the shell lined up, then copied the area of interest and pasted it as a semi-transparent layer over the right hand pic, using the lug of the pot with the grey(?) wire as a common point of reference for the overlay. Voila! the pot travel is about 110 - 120 degrees, making some allowance for the change in camera angle. Check this, by looking at the very first and last frames in the video - the cam is about 30 - 40 degrees "above" the top face of the shell in the first frame. In the very last frame, it is about 80 degrees "below". Again, 110 - 120.

I'm with Gus on the geometry of the cam/actuator giving it this unusually vocal and expressive result.

[Paul Marossy]

No, it's more like 180 degrees, I can see the pot shaft turning approximately 180 degrees when the treadle goes from one extreme to the other. The cam is doing less work than the pot is. It's the amount that the pot is rotated that gives it this distinctive range in sounds - it's way more than the conventional wah pedal, and this is due to the design of the cam.

[R O Tiree]

OK, I'm missing something here - you couldn't shoot it again looking at the pot from the other direction, could you?

[Pedal love]

Its very very nice looking, just gets hard to care about anything anymore.

[R O Tiree]

Its very very nice looking, just gets hard to care about anything anymore.

...which is one way of telling me to drop it, I suppose.

However, in the absence of a gear/pulley system with a better than 1:1 ratio, or another lever arm or 2, or some other system, there is no way that the pot shaft can be rotating further than the actuator arm (aka "plastic gizmo" in Paul's post above).

The older/wiser/more knowledgeable heads on this site are always encouraging people not just to be cooks (copying others' work) but learn to be chefs (paraphrasing a thread from some months ago). Some, like RG, Mark Hammer, etc, spend an inordinate amount of time explaining again and again, from different angles, for which I for one am most grateful. But, that does not absolve anyone from taking time and effort to prove things for yourself, learn the equations and how to manipulate them, researching other resources, so you really understand why things happen the way they do, and not to just accept something just because someone else says so. And we all (should) know that, to make decent pedals, we have to be a combination of artist, elec engineer and mech engineer.

So, if Colorsound managed to design a way to get an extra 60+ degrees out of a simple 2-lever arrangement that only appears to rotate through 120 degrees or so, then I'd really like to know how they did it. If there's extra gearing in there of some description, then that explains all. If not... then it doesn't.

[slacker]

I don't know if this helps or not, but I've got an old FrontLine Wah which is basically a Colorsound Inductorless Wah. The shell and the plastic part look the same as Paul's.
That uses a 100k linear pot, mine measures as 91k, a full sweep of the pedal covers a range of about 41k, which is virtually half the rotation.

[R O Tiree]

41/91*270 = 121.6 degrees. Thanks, slacker

[MohiZ]

Hmm... Am I missing something here? I have a CryBaby with the pinion gear mechanism, that rolls the pot over 240 degrees and actually travels through the whole range of the pot. The only thing I did was that I removed the bumpers from each end of the treadle. The reason the colorsound wah has a wider sweep has to be because of the circuit and not the mechanism, I think.