Penfold wah

[col]

I finally managed to get hold of a broken crybaby at a reasonable price and put the circuit from R A Penfold's book "Electronic Music Projects" into it. I also added the auto wah circuit and made it true bypass so the on/off switch on the wah controls either the manual or auto circuit depending on which is selected from a toggle switch on the side.
This wah is fantastic, and no inductor. The auto wah is also good, sort of like a vowelly tremelo. The only problem i have is that theaction on the travel is all between 0 and 10k on the pot. I intend to change the 100k for a 10 or 22k pot at the first opportunity I get.
This circuit has been posted on the web but I can't remember where. For anyone who wants to build an inductorless wah I'd definantely recommend it, very simple based on 1 IC.

[Paul Marossy]

Sounds cool. Are you planning on sharing any soundclips with us? Or maybe sharing the schematic?

EDIT: found the schematic - http://hammer.ampage.org/files/PenfoldAutowah.zip

EDIT #2: So... did you wire it for true bypass?

[col]

That is a different version. I think there are 3 or 4 altogether. The one I built is a very simple version based on a single op-amp, he suggests a LF351, I used a TL071. The modulation on the auto wah is given by a 7555. It isn't a reactive auto wah like the one in the article, it just modulates at whatever frequency you set it to just like a tremelo. I built the reactive one and it worked occasionally but also made some strange noises. It is very similar to one of the DOD autowah circuits which I built and it worked perfectly. I'm sure I posted that stripboard layout here some time last year.
I know there is a problem posting Babani circuits here but I have definately seen the schematic I'm referring to elsewhere on the web.
I didn't make it true bypass. I was going to use a 3PDT switch but the shaft wasn't long enough for the crybaby shell to operate. I have seen others with the same switch so I can't understand that! I used one side of a 2PDT switch for effect on and off and the other to light an LED in the same way that Guyatone do.
I don't have the ability to record sound on my computer unfortuantely.

[Paul Marossy]

Oh, I see. Still sounds interesting... 

[snoof]

Do post  or link to the schem if you have time, I'd like to see a different version of this crkt.

[DryRoasted]

I have a copy of his book, If the general concensous is favorable I'll post the schem

[ItZaLLgOOd]

I would like to see the schematic.  I have a Snarlin Dogs wah shell that I wnat to use.