struggling with note number modulation

[Josh C]

i'm trying to create a patch where the LFO speed corresponds one to one with the keyboard tracking of the oscillators like certain Polymod effects on other Sequential synths. I have experimented with note number modulation of the LFO speed, but even with the amount of modulation at the highest setting, The keyboard tracking is still wrong. I am aware that the amount of modulation can be increased further by using another mod slot. However, I don't know what amount to set the second mod slot too. I looked at the bit about note number modulation in the sticky with the look up tables, but I didn't find the answer to my particular issue. does anyone have any ideas?

[jok3r]

i'm trying to create a patch where the LFO speed corresponds one to one with the keyboard tracking of the oscillators like certain Polymod effects on other Sequential synths. I have experimented with note number modulation of the LFO speed, but even with the amount of modulation at the highest setting, The keyboard tracking is still wrong. I am aware that the amount of modulation can be increased further by using another mod slot. However, I don't know what amount to set the second mod slot too. I looked at the bit about note number modulation in the sticky with the look up tables, but I didn't find the answer to my particular issue. does anyone have any ideas?

Do you already route the LFO to its destination by the mod matrix? This should multiply the amount of modulation by 4 compared to routing it as destination in the LFO section directly, if I remember correctly.

[Josh C]

thanks for the reply. i'm pretty sure that all that does is increase the LFO amount. I could try it, but I don't think that it will help my issue. after I set the LFO destination, I created a mod slot with the source being note number and the destination being LFO speed. i'm trying to emulate patches on synths such as the Prophet 6 where Polymod is set to modulate osc shape with the modulating osc set to Low frequency mode and keyboard tracking on. I know that this is possible on the Rev 2 but I don't think I know how to do the math to achieve it. if it were set up correctly, the LFO speed would be doubled per octave, But that's not what's happening here. Even the highest amount of note number modulation is still too low.

[timboréale]

Note number doesn't double per octave, so why would you expect the LFO speed to double per octave? It's linear, not exponential.

[creativespiral]

Yeah, the issue comes in that the input values for LFO speed output uses some sort of exponential type of curve, but doesn't seem to be the right curve required to double frequencies per octave (ie: doubling per 12 input values, 24, 48, 96 or something else).   

I remember I experimented with this a couple years back, trying to do what you're doing and document it in the appendix, but I couldn't figure it out what the curve the LFO speed uses, or if there's a way to accomplish the LFO to key track like key frequency.   

I would be interested to know if anyone has figured out what the LFO speed curve is, or if Seq devs have some info that could be shared.

[Josh C]

that's a shame. any idea what the LFO amount curve is?