Changing response curve (for F8R on I2C)

I have an F8R which I have successfully got connected to my ER301.

Am running into an issue that seems like it should be simple to solve but am stumped.

When using the a fader to control something like a filter cut off (in the lowpass ladder filter) it seems like the response is “log”. Ie, a small move of the fader (like 5-10mm) sweeps the whole range of cut off.

What I want is for the fader to be effectively “linear” so that at half way it’s halfway through the range. I can’t seem to get this no matter what I set the bias or gain settings to.

This make me think there needs to be a log to Lin converter or log to exp or vice versa. Does such a thing exist? Or do we need to make a custom lua script to do it?

Anyone out there?

That seems odd. I have two 16n controllers which the f8r is based on and neither have that response. I am wondering if your module was built with the wrong kind of fader.
If I remember correctly there was an issue when Michigan Synthworks built a bunch of stuff early on with audio taper faders instead of linear ones.
I’m wondering if something similar happened to yours?

That’s certainly possible and will investigate. However assuming it’s correct and the faders are producing an audio response, will still need something to convert them.

If you do have the wong faders I’m not sure there is anything simple that would convert them on the 301. Probably your best option would be to play around w/ the gain and offset of each control you are mapping to and just dial in the range to find the sweet spot of what you are controlling.
That is something I do anyway when preparing for performances. I often don’t really need the entire range of a control to correspond to the entire throw of a fader.

Played around with this this morning. I don’t think it’s the faders.

When I map to a linear control (eg. Level
on the Linear VCA module it works as expected). It’s when it’s mapped to a non-linear control (dBs, Hz) that it doesn’t scale the way I’d like.

Am guessing the way to solve this is a custom lua script

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Hope you figure something out!