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R5 is one of the values that is most interdepndant on the rest of the circ being in spec. Generally, lower values sharpen the peaks, going larger fattens / widens them.

In my experience, sharp peaks make interesting wah ( like the early boomerangs or coveted 60s voxes), fat/wide peaks make for more of a sonic schmear, sweeps the frequency but with less distinct character.

In some of my modeling, when other parameters change, i have seen values as low as 700 ohm do a nice job.

it's easy to make a wah quieter or kill off a little treble. it is not so easy to make it louder without getting dirty or get more treble if the sweep is set to low.

one other myth from the internet. that idea that changing the .2 to a .3 on the pot cap will simulate icar taper, real world and spice modeling have both shown this to not be the case very often. in fact, the value of these caps hardly matters at all in most wah configs. in rare cases, raising the one off the C of Q1 up to .7  to .9u can even out the freq plot if there are dead spots.

hell yeah. that is good news

Cool, brian, i thnik this good. Will the caps have 1 meg resistors to prevent popping while turning?
I have seen name brand wahs that do the switching without resistors, the popping is quite loud.

I noticed the pop. Yeah, some resistors would be good here. I'll add those in tomorrow and report back. I'm really in overdrive mode here...trying to get all my gear together for a recording session next weekend!

It's easy enough to modify the existing layout for the three caps, but I'll consider re-tooling the layout in the future so this will involve less off-board wiring. Or, maybe a breakout board like the Fulltone one.

Here are some sweet small rotary switches I've started using, BTW:

http://www.mouser.com/Search/ProductDetail.aspx?R=SR1712F-0204-20F0A-N9-9virtualkey14860000virtualkey105-SR1712F-24NS

sounds cool brian.

those switches look good.

if people are interested in a more old style switch, i can send the following for 6$ each ( current similar grayhill part is over $12 ) it has 10 positions but you can find ways to put stops on the knob, or use all 10 positions!
6$ shipped in US.  if you buy more than 6, price goes down to 4.00 each, mailed in the US. note: 1/8"
shaft. 1/2" diameter, 5/8" deep including solder tabs. nut / washer included.

since the metal is so thin, you can make a dimple on the bottom of the wah as well. use clay or putty to mark where the dimple needs to go, then you can use the same putty to check clearance once the  dimple is made. i use a large socket as the 'die' to pound a smaller socket into to make the dimple.

Cool, brian, i thnik this good. Will the caps have 1 meg resistors to prevent popping while turning?
I have seen name brand wahs that do the switching without resistors, the popping is quite loud.

Chordball, thanks.

A lower gain transistor for Q1 makes it easier to get an even response across the band and makes a more interesting texture to my ears.

One thing that spice modeling / real building back and forth ( i will often do a second round of tweaks in spice after the wah is built to further refine) is that we can make almost any part work, for example high gain trans , but when one part is changed it often requires five  or more other component changes to get back to a 'correct' frequency plot. Hence my reference to playing three games of chess at one time. I am currntly developing a wah that uses a joystick pot from sony playstation controller . The whole thing happens between 5k and10k on a 10k pot!

Cool, your method works, you dial it in til it sounds good to you.
I get your point about great players and great recordings.
I am the same joe gagan. I did not invent the input cap blend, many people had done it before me, but i made such heavy use of it in diy and commercial designs- so much that people started using my name to describe it. Many people have built the easyface since 2000, especially the input cap blend version.

i was skeptical of the freq pot since the weener first came out. in many experiments, i could never get a pot to get a proper sound on two caps for the sweep cap. but i held back my comments as i had not built the weener, still haven't.

as far as getting  a wah to quack, you can move the entire freq range upward via a smaller sweep cap (.008uf for example ) but a lot of this depends on the mh of the inductor. if you have a 500mh inductor, a larger sweep cap is fine. but if you have a 650 mh inductor, the sweep cap might need to be smaller to get the same range.

there is no magic recipe for getting wide range ( except a delicate balance of all the elements involved, very much like tuning a race car for max performance). i have been building a lot of one-off wahs lately, modeling them in spice , then testing, back and forth. what i have learned is that getting the wide range is the synergy of all parts involved, kind of like playing  3 games of chess at the same time. everything affects everything else.
i think the sites that talk about adding a bunch of trimpots sometimes actually adversely affect some people getting good results as it increases the options to the point where it is hard to find the sweet spots.
a few notes:

the R paralleling the inductor is a minor player. mess with it last.
the R off Q1 base/ind is not that critical, in some cases lowering it actually sharpens the peaks, which is IMO part of what makes a wah sound interesting. flatter rounder peaks make for a boring mush. i have gone as low as 800 ohm in some cases.

changing the input r and the Q1 E R are both ways to raise and lower gain / lows or both. but they work differently and are very interdependent. tune both of these together. some whas react better adjusting the bias of Q1 at the collector instead. sometimes i just run Q1 e to gd and use a 100k trimmer on the 9v>Q1 collector

inductor mh and sweep cap are both doing pretty much the same job. once you get the gain dialed in, you can assess changes to the  overall freq curve using either mh or sweep cap changes.
you can move the mh up or down as much as 200mh with polepiece magnets in various configs applied to the sides or top or both. radical mh changes can occur when forcing two polepiece magnets into north/north config ( which they will not do unless taped or glued together)

i like low gain trans for Q1. i use lots of 2n2222s. hfe as low as 70, rarely over 180 for Q1. Q2 doesn't seem to matter much as long as it isn't 600 hfe .

you can get more treble by running a treble jumper 820pf series with 68k r across the wiper and out lug of the wah pot. (NOTE:) you may get squeals in some wahs, try raising the 68k til the squeal stops)

you can also get interesting effects by running a small cap 330p, 480p etc from 9v to q1 collector.

i don't care about output buffers. if someone wants to run a wah before a fuzz, a 250k or 500k pot at output does as good as a buffer anyday.

input buffers can help add treble and even out differences between single coil and Hb guitars.

sorry this drifted off of weener specific info, just thought i would share some of the stuff i've learned.

good to know that the mammoth enclosures are improving. didn't mean to be harsh on chinese enclosures per se.

looking forward to the comparisons as well!

thanks guys!
got the top finished, claudio picked it up last nite, he loves it. had to make a few quick changes to work better with his es335.

before he showed up, i made a quick vid with my strat. this is modded from the previous vid^^, i had to change a few things to get a better volume match to the bypassed signal. you can hear me switch to bypass a few times, the wah is actually a wee bit louder. no other pedals, just a strat with HB in neck position and seymour qtr pound tele Sc lead PU

and the top!
(posted in the next few posts because they wouldn't link in the message?)

Looks beautiful. Appreciate the warning on the mammoth enclosures, i have been avoiding chinese enclosures for the reasons you mention. The boutique wahs  i have bought that used chinese enclosures were a liile flakey.

Thanks!  They are little toroids made for isolation in phone networks. The specsheet says 800mh/15 ohm but when i got them they actually measure average 570-680 mh.

Pot is PEC 50k log.

just built the first with jacob's board. excellent board, a little tight but i could deal with it.

this one has a few mods, 220k input vol, larger input r (33k) to compensate, 500 ohm trim to ground off Q1 E, etc.
making my own inductors from surplus sourced toroids and some R in series added.
i used vintage metal can motorola 2n2222s, 180- 220 hfe range.


here is what it sounds like boosted with a fuzz:

thanks, jacob, job well done!