Random Tone Generator; any schematics?

[Bernardduur]

Hi... I just encountered this device and I wanted to know how hard it should be to build one. I can really use the randomisation of the unit "for the use of good". So can anyone help me?

http://electroharmonix.ronsound.com/articles/rtg.html

[doug deeper]

i played with one once...it just made whale sounds (analogish ones)
just a sample and hold circuit driving an oscillator as far as i can tell.
cool though.
and super rare!

[soggybag]

The maestro sample and hold is alomst what you are talking about. It produces random control voltages that are fed to a filter which filters the guitar signal. As you play you get what sounds like a wah jumping around at random. The voltage from sample and hold portion could be used to control the pitch of a voltage controlled oscillator.

[toneman]

Music From Outer Space has a Random LFO(Low Frequency Oscillator).
(Ray Marston's site)

check out the different osc on his site....
http://www.musicfromouterspace.com/analogsynth/old_synthesizer.html#NOISEGEN

his Random Trigger generator--
http://www.musicfromouterspace.com/analogsynth/multinoisemodule_exp.html

these are random *voltage* generators.
feed them into the voltage control of a VCF.
or, use them to control an opto....

stayrandom
tone

[Paul Perry (Frostwave)]

If someone asked me for somethng like this, here's wht I'd do:

1. find a random noise generator circuit (simplest is the reverse biased transistor type).

2. find a sample & hold circuit (cheapest is a fet as a gate). And a LFO to clock it (prob a CMOS 7555).

3. Use #2 to sample #1, there is the random voltage!

4. Now build a voltage controlled filter (from one of the many Synth-diy sources) that has a resonance control that can go to oscillation.

5. Now, you not only have a random wah (if you run a signal thru the filter) but, when the res is set to oscillate, there is your random note source!

And, if you wnat the lag, that is just a resistor & cap after the sample and hold.

[Paul Perry (Frostwave)]

http://www.media.mit.edu/physics/pedagogy/fab/fab2001archive/electronics/assignment.html
has a schematic (a VERY ROUGH one!)

[tatems]

I found this schematic. It says random noise generator not tone so i'm not sure about it.

[Bernardduur]

I found this schematic. It says random noise generator not tone so i'm not sure about it.

Ok, will look into both options....

THANKS!