Planning: UI

One of the most difficult things to do in a synth UI is to give the user the ability to control many different parameters without muddying the UI or scaring them away by presenting too much information.

The way many powerful synths approach this problem is via a "routing table". They only show the necessary knobs, but then on a separate "page", they give you the ability to map ADSR or LFO functions to those specific knobs.

Other synths solve this with a "beginner mode" and an "advanced mode", that just toggles which knobs are visible.

The method that seems most intuitive to me is to initially only show the basic knobs (beginner mode), but then when a user clicks just below a knob (indicated in some way), it expands a new set of knobs below / to the side of that knob for configuring things like ADSR or LFO.

An example is in the filter envelope: there's a mix knob that controls how much of the filtered signal is mixed into the original signal. That's enough control for some situations, but it would be useful if you could click right below the knob and then 4 new knobs would appear below it to allow for an ADSR envelope.

Even though UI is critical for a synth, since it's not the focus of this project, the expandable knobs should be implemented after everything else is functional.