Vintage Synth Explorer Forums

Hi
I am new to music synthesizers. I am looking for a 3-4 voice analogue synthesizer for a physics experiment. Can anyone recommend which analog synthesizer can do the following?

Analog sine wave output only.

Example:
Voice 1:
1. Start at 1000 Hz and end at 1005 Hz (smooth transition from low to high frequency) Not a digital step
2. Duration 1 / 5 second then pause .1 second then repeat.

Voice 2:
1. Start at 2000 Hz and end at 2005 Hz
2. Duration same as voice 1

Voice 3: similar to above.

All 3 voices on/off duration are in sync.
So what it will sound like is a continuous chirping sound.
It must run continuously (no auto off)

I don’t want to spend a ton of money.
I was thinking opto-couplers might be used to synchronize the on off chirping of the voices, so I may need to wire into or connect to the keyboard circuit. Unless the synthesizer has this ability built in.
Have some electronics experience, but I prefer not to build from scratch if possible.

Nothing off the shelf can do that, or at least not easily.

I can't think of any any synth that allows pitch bends in hZ rather than semitones. So the pitch bend amounts would have to be tweaked by experimentation. A bend from 1000 to 1005 is totally different than bending from 2000 to 2005 (2000 to 2010 would be the same bend as 1000 to 1005). Since those frequencies do not correspond to semitones in A440 tuning, the synth would have to be globally detuned and some sort of frequency counter used to calibrate the tuning. It might be possible to use a synth that supports microtunings to simplify this, but there are no analog synths I know of that support microtunings.

The notes would have to triggered from a polyphonic sequencer that allows editing pitch bend messages. I can't think of a single analog synth that can do that, only digital ones. So if the synth must be analog, you would have to purchase a sequencer as well.

Most analog synths do not have sines available as an oscillator waveshape, many are limited to saws and pulses. You either would need to use a low pass filter to isolate the fundamental (again by experimentation) or use a self oscillating filter where the purity of the sine. If the sine needs to be pure (zero harmonics) it's likely that no analog synth can generate a truly perfect sine wave.

The only analog synths that would have the pitch stability required to get precise frequencies would be those with DCOs. VCOs are not stable enough.

The simplest way to achieve what you want is probably to use software to generate the signals.