Ballistic, inertial and other nonlinear knob responses

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Hi all,

Wondered if anyone had any advice to share re nonlinear knob responses?

I know the Ohm Force plug-ins had a simple "ballistic" model a decade or more ago, but has anyone got any good recent examples - or good reasons not to?

I find that with good quality analogue hardware knobs, you can quite easily get resolution of better than 1/100th of a turn. With a mouse, it's hard to do that without resorting to fine-control modifier keys or unnatural & uncomfortable "rotary" gesture modes (which largely seem to be a thing of the past, thankfully). The natural resolution you can comfortably get with vertical mouse movements is about 20px - yes, it's possible to be more precise down to single-pixel level, but quite fiddly: I'm talking about the response you can easily get with a simple click-and-drag without having to think too hard. But because the "throw" limit is typically around 400px, the effective vertical resolution of the control (for casual movements at least) is kind of poor.

So, any good current examples to look at -- or any concrete argument as to why linear is the only way to go?

Cheers,
Angus.
This account is dormant, I am no longer employed by FXpansion / ROLI.

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If we assume that mousing lacks tactile feedback to the user's hand, any control that moves itself against the user input is only going to make things more difficult. Why I like using a first order lowpass to smooth parameters is that it lets you hear the settings in between, reduces zipper noise, but never goes over or under where it's moved to.

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I wasn't so much thinking of going against user input.

Have one model which uses a quadratic or cubic response from mouse down (gives fine control around the origin value, but plenty enough "throw" to reach the end of the value range in a reasonable number of pixels), but it's not completely satisfactory - doesn't reset the centre value when you stop moving.

So the next thing I planned to try is to add a lowpassed signal and scale sensitivity based on the difference between them - such that the control auto-adjusts to a finer sensitivity if you hover for a short while in a narrow value range.

But I can see this turning in to quite a time sink, so thought I'd ask others if they'd tried similar, or had strong arguments for constant ranging.
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Maybe try using less deviation from linear? Use half sensitivity for fine control and double for fast control.

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I like the "double knob" approach as known from fabfilter UIs.
On the outer 'knob' you do coarse adjust and on inner you do fine adjust
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That's a nice idea, kudos Fabfilter - though our TransMod knobs are already complicated enough without yet another radius for fine control.

If anyone wonders what I'm on about, try A/Bing the sensitivity you can get with high-end Euro gear (Studio Electronics) or much of the outboard available in API 500 series format, compared to software knobs driven from a mouse.

(the inherent resolution limitations of cheap controllers with 7-bit midi knobs is a separate issue...)
This account is dormant, I am no longer employed by FXpansion / ROLI.

Find me on LinkedIn or elsewhere if you need to get in touch.

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Angus_FX wrote:That's a nice idea, kudos Fabfilter - though our TransMod knobs are already complicated enough without yet another radius for fine control.
Make it invisible/transient then.

I kinda like the shift/ctrl for more higher resolution idea, but it could be finessed somewhat, ie more than two resolution/coarseness settings. Could even be done mouse-only.

For example; have three or more 'zones' (imagine them a bit like an archery target, with the centre over the knob), each with a different resolution, from finest in the centre to coarsest on the outside. (Maybe even have the 'target' displayed as a popup semi-transparently superimposed over the knob). Have mouse movement up-down change the value, and switch between the zones based on, eg scrollwheel, or left-right mouse movement.
my other modular synth is a bugbrand

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