This question probably comes from my lack of fully understanding how fm is described as actually being expo or linear (or log for that matter), but how would one patch for exponential as opposed to linear fm on aalto? Is the pitch patched to the index to be mixed? The mod osc? At what attenuation? Why am I wearing this rainbow clown wig?

Linear FM is what the OSC does internally. with linear FM the pitch of the modulated wave stays constant. You can also add linear FM using the linear pitch input to the OSC.

You can add exponential FM using the expo. pitch input, the "1.0 per octave" input.

"Is the pitch patched to the index to be mixed?" I don't understand the question.

I think Aalto's layout is pretty clear as far as what signals are controlling what. For applications and patch ideas, you can check the manual, or indeed, other modular synth manuals.

Thanks randy. I guess what I meant is - is patching for exponential fm strictly within aalto possible.

Edit- nevermind.

So... yup! You can use the expo input to get expo FM. The next question is, what can you use for the modulation signal? There's the LFO, and also ENV2 in repeat mode. Each only has frequencies up to 220 Hz or so. That's by design, so that the potential for aliasing is limited.

Thank you very much Randy, I get it now. I screw myself up on this deal by having a completely backwards tendency to think of 1v/oct from the perspective of voltage and chromatic notes instead of frequencies, and start trying to understand some area like this where that is relevant and immediately get confused. This isn't the first time and you'd think I learn. Will get it drilled in there some day. Again, thanks.