Yet-to-be-named wah pedal

[mjg]

This is a wah pedal that I've been procrastinating on for at least six months now.  I started by reading the RG Keen article, and played around with all the components until I settle on a 4 way switch for the centre frequency, and I've added a pot to control the gain/distortion of Q1.  Used a yellow Fasel inductor. 

Board by Elecrow, and I added a 3PDT and rotary mini board as well, to make the build easier.  I named the PCB 'Yowie' as that seems to be the equivalent of 'Bigfoot' in this part of the world. 





Inside wiring is pretty minimal, but I did need to run ground wires to the backs of the pots and to the enclosure itself.  Apparently the paint that I used was too good an insulator.



For the finish, I have matched it to the guitar that I built last year. I'm using car spray paint (rattle cans), in a red and black, with clear coat over the top.





Then sanding the clear coat down with 600, 800, 1200, 1500, 2000, 4000, 6000, 8000 and 12000 grit paper and pads. After that, a rub with some car scratch remover.  I didn't spend as much time sanding as I did with the guitar, so the finish isn't completely scratch free.  But it does the job. 

[cooder]

That looks absolutely spiffin all around! Nice elbow grease action there on the snading and polishing front!
So what is the circuit based on? Classic Vox wah or...? And you tweaked the values?

[mjg]

Thanks Cooder,

Yeah it's based on the classic Vox wah.  I've made the drain of Q1 a pot, so you can have a nice clean sound, or dial up the distortion.  Also went with 4 caps so you can set the centre frequency of the envelope - I think I used 4n7, 6n8, 10n and 15n.  They all sound distinct, so that's a nice mod. 

More images incoming...

[mjg]

Here's my attempt at making the knobs fit with the colour theme.  I used black aluminium knobs from eBay, and first attempt was to mask them and spray a red stripe.  It looked pretty crap, so those ones got put in the pile of shame. 

2nd attempt was to use the round bit on a rotary tool to make a little concave hole on the top of the knob, and then fill it with some red model paint.  The paint is slightly transparent, so the metal shines through, and it looks almost gem like.  So that's a technique that I'll be using again I think... it looks pretty good. 





Fitting the pin to hold the wah shell together proved difficult for me.  I was hitting it with a metal hammer, and that pin would not budge.  Eventually it got the better of me and I slipped, and made a nice big dint in the paint work.       I've hand painted over it, but it still looks a bit crap. 

[mjg]

Anyway, here are the glamour shots.  One with the matching guitar. 

[cooder]

Very nice indeed! Those knobs worked out great with that little dot too.

[m-Kresol]

great work all around and a lot of effort went into this. tidy wiring too!

[jimilee]

Now that's awesome.


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[gordo]

Wow!

[mjg]

Thanks!

I just have to come up with a name for it now, and do the little name plate on the end. 

The guitar that it matches is called 'Vulcan', so I have been trying to come up with a name to match.  Something blacksmith related maybe. 

Then my partner came out with "Why don't you call it 'Vulcan's Tears', because it's a wah pedal and that sounds like someone crying?"

Holy crap. 

Vulcan's Tears. 

Ok, so decision made, and she will be naming all of my pedals from now on.   

[culturejam]

Such a great project! Very well done all around. 

[mjg]

Thanks!

Forgot to mention, I've got about 5 of these PCBs spare, so if anyone feels the need to get their wah on, I will put up a thread in the 'buy/sell' area.  Let me know if there is interest, as I'll have to do a build doc first. 

[Rockhorst]

Cool, the PCB design looks very nice and the pedal's color scheme very pleasing. That switch, the right inductor and a smooth icar pot are my go to mods for any vox/dunlop type wah. Great build!

What's the cable you used?

[mjg]

The white ribbon cable?  Umm... I think it was recycled out of an old air conditioner that my kid pulled apart for some holiday fun.

For the mojo, of course.   

[Rockhorst]

Must have a 'refreshing' tone then