CV controlling guitar volume and tone

[Toopie]

Hey guys,

This is a question probably not even worth asking around here, but I'm a novice and I'm trying to figure this out.

I'm building a lap steel guitar and I would like to use some LFO's from my Moog CP-251 to controle the volume and tone values on my pickups. Using some jacks wired up to the pickups I guess. Basically I want to create some vibrato like effects straight out of my guitar.

Is this possible? Is it easy? Is it a bad idea? Why?

Thank you guys.

I'll probably have more questions about a Fuzz Factory clone I want to make, but I'll read the forums some more first.

[ashcat_lt]

The easy way to do this will be with LED/LDRs.  The T pot is just a variable resistor, and an LDR parallel to it would probably work fine.  The V pot is a voltage divider, so might need a complimentary pair, though just putting the LDR parallel to the bottom of the pot might work well enough.

[R.G.]

I have this theory that every situation in life has been covered by at least one refrain from a C&W song.

In this case, sure it's possible, and as the song says, "send lawyers, guns and money". 

Maybe not in that order.

I like the LDR approach too, especially for the tone settings. Other ways get complicated pretty quickly.

[Mark Hammer]

How is Warren Zevon C&W? 

Music classification aside, I'm a firm believer that you do on the guitar what is best and most easily done on the guitar, and what is best and most easily done off the guitar gets done there.

Lap steel introduces afew wrinkles.  One is certainly the minimal space available.  I have an old Guyatone lap steel, and there is barely enough room for the single tone and volume control.

Of course, the way one uses FX with lapsteel can be different.  Formal pedal steels can have knee levers that allow for real-time control of volume swells and such.  A lap steel can't have anythng like that.

The alternative would seem to be using foot pedals to control tone and volume.  It would certainly seem to be possible to use an expression pedal to control tremolo depth and/or rate, as well as volume swell, and treble rolloff.  But there is no real need to make the expression pedal control something inside the lap steel itself, as opposed to a floor pedal.

[ashcat_lt]

But there is no real need to make the expression pedal control something inside the lap steel itself, as opposed to a floor pedal.

This is a good point.  You can use the same LDR tricks at the other end of the cable and will still work about the same, save space in the instrument, and probably be much less hassle. 

[PRR]

> not even worth asking around here

No question is too low for this gang.

This question is right down the center anyway.

> use some LFO's from my Moog CP-251 to control the volume and tone

"Tremolo".

Unless you really wanna butcher a Moog, or must VFO your LFO, you can hack-up an LFO real easy.

"Trem pedal". Most wobble the volume, that's most obvious to the ear. There are tone-control tremolos: Leo held several patents and at least one production model before he figgered that volume wobble was good enough for his customers (and he started with lap-guitar amps, though he was up to Bakersfield with Broads and Strats by the time he was wobbling sound).

[Toopie]

Helpful stuff here!

I'm going to try and wire up this little optocoupler circuit and see if it could possibly fit into my guitar.

I'll only have one pickup anyway, and no string through body tremolo bridges, so I'll probably find some room easily. Hell, I can route holes wherever I want!

My reasoning is just that this lap steel guitar is meant to be integrated into my synth set up. More of a desk steel, if you will. If I'm running LFO's to and from my synths, I might as well try and find a way to run them into my guitar as well. It seems as though I can achieve this simple tremolo effect relatively easily, and then I can use my MF-102 for other things.

Somehow I like the idea of this vibrato effect being integral to the guitar, giving it its own character. And if it doesn't end up being used ever it'll just be a little failed experiment, which is absolutely fine.