These patches transfer 4 DC control signals between 2 Slots (or to NM's) by AM modulation of multiple carrier frequencies. modem1 has 4 constant modules that control a simple sound generator (a saw osc with a filter), and plays this sound on the left channel. The constant values are also modulated on one single channel and fed out of OUT4. modem2 has the same saw osc+filter on OUT2, but instead of the 4 constants it decodes the modulated signal from modem1, and uses these values to drive the osc & filter.

If all is working well, you should be able to control slot A and B from the knobs in slot A, and both should generate *almost* the same sound. Since the modulation/demodulation is quite analog and need exactly tweaked filters e.d., the values differ a bit. But it should be sufficient for amplitudes and filters etc.

This can also be used to connect 2 NM's together. If you need more control signals, simply put in more filters in modem2, and enable more osc's in the sinebang in modem1.

Usage:

• Plug a cable between OUT4 and Input-L. Don't feed it through a mixer, this wil distort the signals. I suggest you don't listen to OUT4 too loud.
• load modem1.pch in slot A, this is the sender
• load modem2.pch in slot B, this is the reciever
• Select slot A and play with the knobs. Both patches should make the same sound controlled by the knobs on modem1.

There are probably a dozen other techniques that can be used to do the same thing (PM, TDM, etc) but I think this one is quite lightweight in DSP usage.

I guess the important question would be: how much is the patch load for the modem.

18% + 13% for 4 parameters, but if you can limit yourself to a total of 4+4 parameters you can actually use *three* patches, since you have two audio ins. J

I do think it might be possible to get more parameters through each line, with some careful tweaking, but it may need steeper (and more expensive) filters. I'm currently searching my vague memories of electronics too see if there is another solution, but I haven't figured one out yet.