He needs to take the controls people know and understand and replace them with cryptic methods that require new learning, and are hidden from view by default. Otherwise no one will take it seriously as a modern UI.
To be fair, knobs as shown in the screenshot are afwul in an usability’s point of view (how do i rotate this, how to fine tune the value), but they convey the information in the context of music plugins really well for the person most likely to use them.
A lot of DAWs use these. With the ones I have used you click the knob and then drag (up to turn the knob left, down for right). It's really horrible actually.
Right. Physically, potentiometers are semicircular sliders.
But another advantage of knobs is the ability to turn them, quickly and yet accurately, with thumb and first finger. Some even have push-pull gear reduction, to go between fast and accurate.
So you'd think that a GUI knob would use some analogous two-finger twisting gesture. With thumb and first finger.
Which is awful and anti-intuitive--far worse than merely non-discoverable. It looks like a familiar control system that a hardware synth would have, but it's actually just a skin on a vertical slider: so it not only forces you to learn a different interaction anyway, but on top of that it lies to you about what it's doing!
Skeuomorphism worshippers have a lot of nerve to complain about abstract GUI philosophies when their own cult hasn't eradicated these design atrocities. Gosh, it sure looks pretty though...
I think you may have forgotten
to add "imho", otherwise the message looks like its telling an indisputable truth. Audio professionals don't complain about skeuomorphism and philosophies and certainly there're no worshippers, as nobody cares about the new fancy names of mainstream visual styles (btw non-skeuomorphic knobs are quite common, e.g. Ableton).
From my own experience, knobs are far superior to sliders in audio applications, as all the adjustments are typically guided by hearing, and sliders' values can jump if you click in a wrong place. This just disturbs the flow. Most of the work with audio software UI is fine tuning parameters, often by a few percent, so relativistic nature of click-drag is perfect for this. Sure, there're relativistic sliders, but they feel rather unintuitive.
He needs to take the controls people know and understand and replace them with cryptic methods that require new learning, and are hidden from view by default. Otherwise no one will take it seriously as a modern UI.