Musical instruments are hardly the only things that now use software. Toothbrushes, toasters, and toilets can now sprout a dozen buttons and blinking lights. It’s no surprise that the designer, daily immersed in state diagrams, flowcharts, and circuit layouts, might eventually surmise that what needs its teeth cleaned is just another computer. The same point is made by the story told of John XXIII, who rejected an architect’s blueprint for the papal apartments with a scribbled Non sunt angeli (we’re not angels): there were no bathrooms.
However, unlike most consumer appliances, musical instruments demand quality XD. An instrument with poor XD is simply abandoned: it’s socially more acceptable to not play the oboe than to not brush your teeth. Because of this, instruments make good models for XD. Here are some examples of these musical concepts in extramusical contexts.
- ? Videogames from the 8-bit era imitated a pressure-sensitive gas pedal by augmenting a simple on-off switch with PID control. The longer you held the button, the faster you went; and when you let go, you slowed only gradually.
- ? Handheld devices repurpose four on-off switches as a scrollwheel, a secondary input. Tokyoflash’s wristwatches have raised to an art form both these scrollwheels and riotously nonintuitive mappings from hh:mm:ss to pixels.
- ? When analyzing mouse behavior in a viewer of 3D worlds, an end-to-end mapping considers how mouse-pawing and scrollwheel-flicking might unnaturally stutter a rotating gaze or a highlight moving down a menu.
- ? Consistency, continuity, coherence. Online games that charge monthly fees have excelled for a decade at giving users a sense of mastery with little sense of astonishment, at time scales from milliseconds to months.
Of course, trying to enumerate every application of these principles would produce a list that was obsolete before it was finished. The best summary for what musical instruments have to offer your own XD is pure metaphor. Imagine someone brushing their teeth or toasting bread as emotionally and expressively as rocking out with a guitar.