guitar synth

[Harry Bissell]

Guitar Synth (my HO)
1) you need a Hex (humbucking) pickup to get a reasonable guitar
synth... the best deal
in town right now is at Guitar Center... the G-VOX system for $49 (US).
Cut off the pickup and discard the rest. These pickups are also made by
the evil empire Rol^nd.

2) Mount on the guitar using a better method than the "suction cups" or
"sticky tape".
I made an aluminum platye which attaches to the studs of the
"Tune-o-matic" bridge on my guitar.

3) Choose a method... Select one string at a time (cheaper but Mono) or
one circuit for
each string (Poly)

4) Low pass filter each string, and then extract a square wave at 1
octave down. IMHO this is the only way because without the divide by
two, the square will be varying in pulsewidth and will sound like a
"Fuzz" guitar (which is good also...)  Circuits for this might include
the "Octave Divider" by Craig Anderton, the Korg Octave divider, Boss
Octave divider, DOD octave divider.... or the Electro-Harmonix Guitar
Synthesizer...
Check out Guitar Effect web sites to find these schems. Most of these
have the LPF built in before the divider... You can tailor the values to
make it work much better, you only have to deal with about an octave and
a half... (allow frequency room if you use extreme whammy bar...)

5)  Waveshape the square... you can get a triangle with an integrator
but watch out... when the input stops the divider will be either high or
low and the integrator will saturate at one rail unless you reset it
somehow... Once you have the Triangle use a Tri to Saw converter
triggered by the square wave in (DON'T use a comparator because you
can't guarantee the triangle wave amplitude as frequency varies... The
difference will probably be plus/minus 4db which isn't too bad.

OTOH you could just filter the square wave... LPF will give a
quasi-triangle, HPF a quasi-sine.

6) Make an envelope follower and VCA to set the ampltude of the
waveform. You can add filters, ASDR generators, etc to get a more
"synth" sound.

7) DO NOT bother with "pitch to CV" converters they are IMHO way to slow
in tracking. (There is the AXON pitch to midi which is supposed to be
fast but I haven't tried it...)

8) If you are less "DIY" I'd get the hex pickup and run through 6
multi-effect processors...
or get the V-Guitar from the evil empire....

:^) Harry

farky at ix.netcom.com wrote:

> Hey folks.
>
> What would be a good way to convert analog guitar signals to analog
> synth-sounding signals?
> Do integrators really do the trick?
>
> Toby
> --
> http://pw2.netcom.com/~farky/farky.htm