DIY Mccoy wah isn't any good... what should I do?

[JamMan]

Hello all,

I've been following this great forum about a year now. This isn't my first post, but nevertheless, let me introduce myself quickly...

I study mathmatics in Finland, although my greatest passion is music (guitar) and all kind of gear related to music (like the mighty Mellotron)...  Except for anything digital... During the last year I made all kinds of DIY stuff, like one tube amplifier, the mosfet-booster, a tube preamp, the PT-80, two germanium Fuzzfaces etc. I have to say I'm completely hooked to this hobby.

Now, to my actual question. I made the Mccoy wah from the great fuzzcentral -site. I chose to made my own perfboard layout, I tried to keep the alignment of the parts the same as in the PCB -layout. I also made the output buffer. I decided to use a bit different parts: a Fasel inductor (yellow), Blacktop Deluxe pot and high quality capacitors (Xicon, if I remember correctly). I had an easy access to these parts. The wah was housed in a crybaby.

The problem is that this wah doesn't sound very good. It's OK, but really I think it "should" sound better. Also, I get a terrible hum, if I use it within 1 meter from my power supply, the Cioks Big John (kind of disturbing name...). What could be the cause for these problems? I think my wiring is OK, also the layout is correct. Still, could it be the layout?

I'm thinking of different possibilites here: I could build it again using the PCB, or I could be using my alternative parts to make a crybaby (if they are better for that), or I could just buy the damn thing. The picture wah sounds tempting, though it is expensive. What do you guys recommend I should do?


Thanks for any advice!

[Johan]

does it hum when batterypowered too?..if so, you probably made a mistake somewhere, if not, the filtering of the powersupply might need  a checkup...or the scheilding of the wha, if the inductor is picking up the transformer in the PSU.

and it could be that you simply dont like the "McCoy"...I dont, I prefere my GCB95 Crybaby (stock ) to any of the Vox-versions...but on most internetsites that is "crasy-talk from someone with bad taste.."
..I like the agressivness of the GCB95 and find the voxes mellow and uninspiring...but that is just preference...

johan

[trjones1]

You should try different transistors.  There's a big difference in sound for different types.  Put sockets in and experiment.

[Paul Marossy]

Try building a Maestro Boomerang with a yellow Fasel inductor, MPSA18 transistors and 10uF tantalum caps on the output. I like this over all my other wahs, which is six other various makes and models.

BTW, inductor based wahs are very susceptible to EMI, especially with a high gain distortion. I have found that generally the wah needs to be about 24" away from any wall warts to not pickup a hum.

[JamMan]

Thanks!

Yes I forgot to mention, I run it with batteries only, still it picks up considerable amount of hum, when near (<1m) the power supply. I have no former experience with wahs+powersupplies, so the same problem could occur with other wahs also. I have to check that.

About the transistors... Yes, they could be the problem also, I'm using BC109's but I have no idea if they are of good quality or not.

Try building a Maestro Boomerang with a yellow Fasel inductor, MPSA18 transistors and 1uF tantalum caps on the output. I like this over all my other wahs, which is six other various makes and models.

BTW, inductor based wahs are very susceptible to EMI, especially with a high gain distortion. I have found that generally the wah needs to be about 24" away from any wall warts to not pickup a hum.

Maestro Boomerang? Could be interesting, thanks for the hint! This remark about inductor based wahs could very well be true, although in my case I can hear some noise even with a clean sound.

[Paul Marossy]

Maestro Boomerang? Could be interesting, thanks for the hint! This remark about inductor based wahs could very well be true, although in my case I can hear some noise even with a clean sound.

I never heard of the Maestro Boomerang until I read about the Geoffery Teese interview at this page, http://www.analogman.com/kraft.htm - he rates it as next best after the Vox Cldye McCoy. I love mine, it's the best sounding wah I have ever used.

Yeah, sometimes you can hear some hum even on a clean setting. It depends on how bad the EMI is in your surroundings.