advice sought for "new" guitar effect

[pinkjimiphoton]

hey guys,

new "maybe cool idea" time again..

i'm envisioning a "talking" kind of effect...

so i'm hoping i can kind of condense a couple different ideas into a coherent pedal.

thinking envelope follower stage sweeping two stages of formant filters, adding a switchable lfo to the filters, and having maybe an lm386/ge diode kind of distortion circuit to drive it with..nothing spectacular tonally, just something to wallop the filters with. put it in a wah shell, and add two switches...one to kill the envelope so the foot treadle can drive the formant filters wah style, and one where the treadle's pot instead controls the speed of the lfo, set to sweep the formants up and down also with the envelope off.

kinda like a formant autowah, but where you can have it auto sweep the formants with the lfo and control it all with the treadle.

i wanna try and build up a workable project to vero and build, but am seeking advice onto which would be the easiest ways to implement these kinda ideas...it seems like it may be a cool pedal to try and produce.

i'm still a newbe, so not sure what's the best way to proceed..what do i do, run a search for data sheets for lfo use, envelope use, etc? i'm thinking just the most basic kind of effects, something with low parts counts. being able to copy parts of different pre-existing circuits to make this hodge podge frankensteinian monster would be cool.

but i don't really know where to start looking. i know i wanna use this as the clipping part...low parts count, and sounds great...makes a great fuzz with the addition of an 1n34a diode clipper on the output:

http://www.forrestwhitesides.com/node/93

so i'm kinda thinking that as the first stage of the circuit into maybe this:

http://www.geofex.com/article_folders/sing-wah/sing-wah.htm

rg's information here seems perfect,  so that would be stage II of the pedal.

so....thinking the lfo from the uglyface would work, too, right?

http://www.diystompboxes.com/smfforum/index.php?topic=70747.0

so all i need to know is, how do i hook up the lfo to rg's circuit, and what is the easiest way to implement an envelope follower of some kind to shape the formants with via just the guitar signal itself?

too many questions probably, but as usual, i can kinda hear this thing in my head...and i'd imagine it would sound close to the ludwig pedal. what do you guys think? is it doable?
is there an envelope follower out there that exists on a chip or something?

thanks for reading this...

[pinkjimiphoton]

this looked kinda interesting, on a side note..

http://yusynth.net/archives/WirelessWorld/Chatterbox-1976.pdf

[kristopher612]

you might try the LFO from the Causality Mk2 phaser by frequency central with the Wax n Wane LED mod.  it would let you use LDRs as mentioned by RG to switch between two different cap sets for something lik the oo and ah frequencies.  you could also try the envelope detector from the mid-fi clari(not) schematic.  it uses a 386 and LED/LDR combo so you might be able to get it and the fuzz from one.  i don't think it would do both form one, but you could try.  good luck!

[Mark Hammer]

In past, I'd described here an idea for a "talked-to" pedal.  The idea was something that used voice parameters productively, but was not a vocoder, or anywhere near that complex.

Looking over the linked to Wireless World article, and the rather non-linear relationships between formants in producing sounds, it occurred to me that maybe the way to attack it is via a foot and mouth symbiosis.

Imagine, if you will, a pedal that has two sweepable bandpass filters.  Common enough, eh?  One school of thought has them sweeping in the same direction together, with some preset degree of stagger.  The sweep could be foot-controlled, or envelope controlled.  Another school has them counter-sweeping by either of those two methods.  Counter-sweeping, in a productive manner, can be tricky with a foot-controlled sweep, simply because....well...pots may not possess the taper you want.

But why do things only have to be foot or envelope, and why does the envelope have to be guitar amplitude?  Why not sweep one formant with your foot, and the other one with your mouth?  The mouth-swept one could be something like the old EHX Soul Kiss, but it could also be something like a Yamaha breath-controlled sweep.  Or, the filter center-frequency could be controlled by the amplitude of a voice mic input.

The beauty of this approach is that one is freed up from having to rely on the stagger of two sections of a dual-ganged pot or the tuning of two yoked envelope followers.  And, of course, it wouldn't sound like anything else on the market.

[Earthscum]

Funny... I use my tj Wah and nurse quacky like that. In my normal setup, I have my wah right after my NQ. It is a higher resonance than the NQ. When I screw around home, I have put the NQ after the wah. The fun thing is that in that setup, the more the wah opens up, the more sensitive nq gets, and it sweeps more. You can really get some crazy mouth sounds out of it, and having the wah first gives another little realm to work with. Either way sounds neat to me.

I'd make the filters switchable series and parallel, but if you do series, I'd recommend the foot control go first.

Also, the reason I popped back in, what made me think of this thread: http://runoffgroove.com/phozer.html

May be some ideas in that, as well.

[marmora]

Ideas:
http://www.diystompboxes.com/smfforum/index.php?topic=26947.msg181177#msg181177

[Ronan]

I have a couple of ideas.

If you want low component count + envelope filter + 2 formant filters, have a look at the electro-harmonix Bassballs circuit. I spent some time with this circuit on a breadboard having one filter controlled by the envelope and the other by a mechanical pedal with pot. I could get some vowel sounds, sometimes limited, sometimes quite good, and the possibilities are there for sure. With one filter disabled it made a great touch wah by itself (IMO).

2nd idea. I bought a bad horsie Morley wah pedal for cheap. It is built strong and has a lot of room in it, a lot of room for a huge PCB if required. As you proly know it uses an LED/LDR to vary the resistance to the filter, instead of using a pot. I found it possible to modify the black card that swings between the LED's and the LDR's with a scalpel, and to cover existing windows with masking tape blacked out with black permanent marker. There is room for 3 LED/LDR pairs. A great chassis for the experimenter.

I can't help with the LFO, for talking sounds I feel I need some sort of control and an envelope filter is at least controllable by how hard I play. But I'm just scratching the surface so what would I know.

[Ronan]

Some more ideas. The soundclip of the ehx talking pedal is about as good as it gets, as far as I can tell.

http://www.tonefrenzy.com/effects/electro_harmonix_talking_pedal.html

http://www.freeinfosociety.com/media/pdf/4101.pdf

http://www.diystompboxes.com/smfforum/index.php?topic=25843.0

[Mark Hammer]

Note the 10k pan pot in the EHX Talking Pedal.  At one end is a clean stage, formed by A1.  At the other end is a distortion stage, formed by A2 with a diode pair in the feedback loop.  Some users would have probably stuck their own distortion in front to provide mre harmonic content for the filter sections to work with, but just in case you forgot yours at home, EHX remembered to pack one.

The "Talked-to" arrangement I described in an earlier post would work well with the TP circuit.  A foot pedal controls the resonant frequency of the one bandpass filter, and your voice could control the other via an envelope follower.