Colorsound inductorless (twin-t) wah schematic

[analog kid]

Does anyone have a practical layout done for this schem that they wouldn't mind posting?? I am not great with making them , even with a simple and small crkt like this but probably could do with a bit of time. Just thought It would be easier to see one that someone else uses to give me a 'template ' to go by or use.
thanks

[Noplasticrobots]

I'm trying to breadboard this circuit using the most recent schematic from above, but I don't know where any connections are. Does the 5M7 connect to the C, B or both?

[trevize]

there's a pcb on paul marossy webpage.

i built it and works fine.

http://www.diyguitarist.com/PDF_Files/ColorsoundWahPCB.pdf

as always, thank you paul marossy!

[John Lyons]

Hey Paul

I've tried to open the PCB for the colorsound wah a few different times in the last week...I get it to open but the page is blank and says its "done".
Is this just me?

[Paul Perry (Frostwave)]

For another twin T wah, PAIA did one in a Poptronics article in the late 60's and also did a leslie simulator that way. I think it was the "Synthespin".

I think Mark Hammer has the Synthespin article here:
http://ampage.org/cgi-bin/hammer/index.cgi?cmd=lt&xid=&fid=&ex=&pg=4

[RedHouse]

Hey Paul

I've tried to open the PCB for the colorsound wah a few different times in the last week...I get it to open but the page is blank and says its "done".
Is this just me?

It is probably your Acrobat reader version, update and you should be ok.
(that did it for me anyway)

CD, I'm surprised anyone is bothering to help you with the kind of reply's your posting, are you having a bad day?

[The Tone God]

CD, I'm surprised anyone is bothering to help you with the kind of reply's your posting, are you having a bad day?

RedHouse, I'm surprised anyone is bothering to reply to a post almost two years after the fact.

Andrew

[cd]

CD, I'm surprised anyone is bothering to help you with the kind of reply's your posting, are you having a bad day?

RedHouse, I'm surprised anyone is bothering to reply to a post almost two years after the fact.

Andrew

ROTFLMAO - there's a verified schematic, a layout, and a frequency response graph.  I'll let the USEFUL information in this thread speak for itself.

[claytushaywood]

I recently built this circuit on vero according to the layout at tagboard fx... http://tagboardeffects.blogspot.com/2012/03/colorsound-wah.html#comment-form

It was made according to the schematic at beavis audio... and it doesnt function correctly as it was.  acted more like a tone control being turned up and down.  I found this schematic and have tried to change my current vero board to match this schematic... I changed the two 100n caps on the left side of the board to 10n, and I changed the 33k resistor on the right side of teh board (the one in series with the sweep pot) to 470ohm like the schamtic from the previous page of this topic.  And now it's getting a LOT closer. 

However, the sweep is messed up.  It doesnt do much in most of it, then it jumps and quickly shifts from bass to treble in the middle of the pedal sweep.  I've tried adjusting the treadle.  But I think it's either the pot of the circuit.  I built it into a standard modern GCB95 crybaby, which I nkow has a 100k pot, but I dont know if its audio or linear taper.  It kinda seems like its an audio taper and a linear taper might suit it a lot better.   I know you can convert audio pots to linear but I'm not sure how... I've searched all over, but I'm not sure how change the taper without changing the actual value of the pot if anyone could point me in the right direction, that would be awesome!

Also, I'm not sure my vero currently matches up with the shcematic here.  It has those changes right now, but I'm not sure i have the 100n caps and 10n caps right....

And... currently my sweep is backwards... toe up is treblely and toe down is more bassy.  And although the pedal is working better than it was according to the beavis schematic and tagboard layout.  I still dont think it gets bright enough at toe up position.  As I said I've tried rearranging the treadle position on the pot.  But thats not helping.

Any input or direction would be greatly appreciated, I'd love to help get these schematics right and give credit to the guys that pulled this schematic here together!
THANKS!

[alberdmonak]

Thanks for this useful circuit!

(Just a question: can i transpose the twin-t part to a valvecaster circuit without changing any values of the components?)

[ringworm]

here are some scans of an original board





gutshot



The pot was a 100k linear but that relies on having the colorsound type gear. A 100k log pot was used with a rack and pinion gear version of this circuit that was made by Frontline in the 80s, that should work with a crybaby rack and pinion setup.

In top image, the resistor on it's end in the top right is 33k
In top image, the resistor just hidden by the cap at bottom left is 100k
Transistor is C549C (i assume it's same as BC549C)
Markings on the polystyrene caps have faded, can just make out 2n2 on the one on the right. Second gut shot shows a 4n7 rather than 6n8.
Hope some of this helps.

[joegagan]

i believe zak said a long time ago that the the wah probb was based on the colorsound inductorless. it has nice squishy, rainbow, or candy like sound.