Seek wah (NO CLONE)

[The Tone God]

I choose the 4093 because there were available, made a low part oscillator, and most importantly I needed the gate functions for the v2.1 random mode. I did suggest in the v2.0 article that if you don't want the random mode you can replace the whole 4093 with any clock source that could drive the 4017 properly. Options include a simple opamp, transistors, flip-flops, and other gate ICs circuits.

There are 555s with CMOS output that would work fine without the need for interfacing circuity.

Andrew

[analogguru]

I think a standard 555 should also work here, cause it has a push-pull output. Current consumtion wil be a little bit higher.  Even a 4011 should work.

This was a "quick and dirty" design, so I chose the 4093 cause it is a Schmitt-trigger-NAND-gate and for this will produce a nicer square wave.  Even when there are no problems by interfacing the 555 to a C-Mos input, in "quick and dirty"-designs i don´t make any risk, that there maybe "could" be problems.

I even didn´t test this circuit, but i am sure that this will work, cause I used this building blocks successfully in other designs.  For the reason that nobody pays me money for this circuit I didn´t want to spend much time for development that some friends have something to play around.

IMHO this is not a serious effect, it is only a novelty.  So the circuit can be modified and improved in many ways.

If you like something serious you can figure out this concept:
Analogguru´s Cool Pigeon

But first you should be able to play this for at least 5 minutes without a mistake:

http://www.youtube.com/watch?v=Ij-z6rAu2Yc
http://www.youtube.com/watch?v=sS9jVdQJs-M

The guitarist of Kid Kreole could do this in 1982 for 7 Minutes and 35 seconds:
http://www.rockpalastarchiv.de/rn11.html

Here you can find a guitar primer for the riff:
http://www.kidcreole.com/Pages/avframe.html

Good luck !

analogguru

[widdly]

Novelty you say?  I've got my geo-fex sequencer hooked up to a moogerfooger LPF, and with the resonance turned up full it does that computer sound from old sci-fi movies.  I can do it for at least 10 minutes while doing the robot at the same time. 

[Processaurus]

I really like the note triggering the clock on the sequencer idea, here's a twist on it, have a sort of adjustable decay/hold on the triggering so that if a note is detected before it resets, it will ignore it and not clock the sequencer, but once it has, it will patiently wait till the next note.  Even be better than tap tempo, because it watches you instead of going off on its own... Maybe just a good pluck detector (which would take more parts than the sequencer probably), and a 1 shot with an adjustable duration.

That video is pretty ridiculous, but I admit I had to grab my guitar and learn that part, thanks.

[ech0es]

Do you have a PCB layout for it ?

[analogguru]

Novelty because its only for home use.  I won´t beleive that you will get reproducable results in a live enviroment. the rhythm is predetermined by the seek-wah, in home no problem cause you can adjust your playing to the seek-wah rhythm. But in a live gig nobody will care about the seek wah so therewill occur synchronizing problems.

Do you have a PCB layout for it ?

Sorry no, this is only a "quick and dirty" design (10 minutes on the toilet) to give some curios guys something to play around and show how this (seek wah) can be achieved - never tested or improved.

In a "commerial" design for example I would not use a LDR, I would use a transistor or fet instead.  But this would need more development time which i didn´t want to invest.

I really like the note triggering the clock on the sequencer idea,...

I like the modulation/trigger feature.
If you turn the speed up, odd potis CCW, even potis CW  you can get:
wah, waaah, waaaaaaah, waaaaaaaaaaaah on every note trigger, a new "tremolo/vibrato/wah effect".
can be realized with a 4046.

analogguru

[MikeH]

Analogguru- I'd like to play around with this, but I have a couple questions.  The 4022 has a leg labeled "inhibit" on your schem; I googled the datasheet, and it doesn't appear to have a leg labeled "inhibit".  There's a "Carry-out" and a "Clock Enable".  What is the "inhibit" supposed to be?

And R10 is labeled "100E", What does that mean?

Thanks.  This thing looks wicked cool.

[The Tone God]

Inhibit == Clock Enable

Andrew

[analogguru]

100E = 100 "Einheiten" (german) = 100 units = 100 ohm

It is used to make schematics more readable even after the third copy.
The "Omega" easily can be confused with a "0".

Also I use 3k3 instead of "3.3k" to avoid confusion with 33k, or 4µ7 instead of "4.7µF".

analogguru

[MikeH]

Ahh.  Mein deutsch ist schlecht. 

That means "My German is bad" right?

[analogguru]

You are right, sir.

If you don´t like the Dr. Q style wah you can switch to the:
Bespeco Weeper
or the
Colorsound Wah-Wah (RI)

Rumours say, the second should sound more "Zvex-ish".

analogguru