2 replies to this topic

[wicked1]

So, I mentioned in the cv2 thread I wanted to build a midi analog synth. I don't know if the cv2 project will work for it, and the more I plan, the less I think it will.
But, it's worth trying, so here's my idea.

It's a 3 osc synth, 3vcf, and 3vca's. LFO's and EG's will all be digital, thanks to cv2 . Basically that should be enough to give one complex voice, or use all 3 individually for simple poly. The idea is that it's usable for most standard playing w/out any patching, and all settings would be saved.. basically like a virtual analog synth.

The down side is it would need more than 8cv's. At a minimum, 16. 3 vca, 3 filt freq, 3 filt res, 3 osc tune, 3 osc pwm (and I'm over 16).. So then I'd still want 3x osc fm.

Analog implementation would be 3 oscillators with their 4 wave outs going to analog switches (like the CGS analog switch matrix. Gate=switch closed), to select the wave. The selected wave to another switch to select the filter mode (the filters I'd likely use have 3 in's, but you could put the switches on the output if they have 3 outs), then from the filters to the 3 VCA's, mix the signal and out. Few other details and switches, but that's about it. I think the switches could be controlled by douts.

I'll attach a quick sketch of a panel I made. I use the "frac rack" format.. 3u. It's 10 frac units long (1.5" per u) which is the size that fits in a standard 19" rack.
It's dirty, incomplete, things aren't aligned, but it's a general idea of what I want to build. All the jacks at the bottom are copy/pasted from something else, so they're not really dividers. Those would be the jacks for all the parameters (vco, lfo, vcf, etc in's and out's) for standard CV control. Big circles are buttons, small circles are LED's

So that's my dream project. Is there any way the CV2 could control multiple aouts? Even multiple CV2's, but for the idea to work they'd all have to be controlled by one primary cv2, to set and store the parameters.
or, is there a different way to accomplish the same thing?

Attached Files

•  synth09.3-Model.jpg   128.65K   42 downloads

[TK.]

My feedback once I'm back from business travel.

Best Regards, Thorsten.

[wicked1]

I'm trying not to think about it too much, because it's probably still an impossible project for now..

But I might have thought of a way to integrate the modulation matrix into the control surface. (Might want to look at the image real quick to know what I'm talking about here..) Since there are a limited number of predefined parameters on my control surface, I've made a little matrix per section. Since each CV can have 2x lfo and 2x eg, you basically select the parameter you want to change and the lfo or eg number. Then the lfo or eg section would light up which of the 16 available is selected. For example: Press PWM, then LFO2, adjust the knob for the level it will be affected (the depth, basically). Then over in the LFO section select your LFO and set the parameters. Say it's lfo6, there. Then you could select osc2, pwm, lfo#, and in the lfo section press 6, and osc2 would have the same pwm settings as osc1.
For the filter, you select freq or res, and which of the eg/lfo you want to set. It's not on the sketch, but I'd need a vca section too.. Just button to select the eg/lfo and set the level.
There are still some important details and options missing from this scheme, but I don't want to put much time into it yet. Thinking about it more, I can also see where you could get lost in the settings, but that just needs some extra thought. Like maybe selecting the VCO number automatically selects the VCF and VCA, too. Slightly less interesting live-play possibilities that way, but easier.

--Guess I should mention, while working on this I've had ideas for a general cv2 control surface. It would be the same size, no set osc and filter, etc, sections. Basically more complex LFO and EG's, and I've been trying to come up w/ ideas for the mod matrix to assign it all to the cv's. I'll follow up on that in a new thread if I continue it. My idea on that is less generalized, too, I guess.. It's more of an ultimate time synchronized modulation box, than a midi-cv converter. I'm still trying to figure out how to integrate the little sequencer into that design.

Attached Files

•  synth09.3-Model2.jpg   133.93K   23 downloads

Edited by wicked1, 04 May 2012 - 19:15.