Accessibility: Exaggerated Playback mode
In general, everybody wants playback to sound as realistic as possible. This means:
- Disabling certain playback effects on instruments that cannot play them in real life.
- e.g. single-note dynamics (SND) on the piano.
- Enabling certain playback effects by default, because that is how musicians tend to play.
- e.g. playback is legarto by default, so slurs have no effect (except on Piano and Flute)
However, playback is not just used as a performance simulation, it is also used as a feedback tool to enable users to listen out for notation errors. In some situations, it may be desirably to sacrifice realism in return for an ability to identify the form of notation currently in use by sound alone.
Who would it benefit?
This would be of particular benefit to users who are blind or partially sighted, as it would enable them to tell whether a series of notes is slurred just by listening to the playback. This means they would not have to navigate all notes with the arrow keys, and wait for the screen reader to announce "slur start" and "slur end" in the relevant places.
It would also be benificial for sighted users, who have complained about the lack of slur playback in the past, and may prefer to have such notation audibly distinguished from standard playback, even if this is not how a real musician would play.
Exaggerated Playback could be a new form of playback mode, with the current mode labelled "Performance mode" mode (or "Standard mode" if we want to save "Performance" for a future mode that emulates advanced - and highly subjective - techniques like rubato).
My suggestion is that in Exaggerated Playback mode, MuseScore would ignore all per-instrument playback settings defined in the score and in Instruments.xml, and would instead use a standard sound for each form of articulation. This would enable articulations to be identified by their characteristic sound, such as a gateTime of 90% for normal notes and 100% (or even 105%) for slurred notes, regardless of the instrument playing them. Similarly, single-note dynamics would be enabled for all instruments.
The current Play button could be turned into a toolbutton menu, just like the note input button, where clicking a small arrow next to the main button expands a list of playback modes.
However, the note input button's menu is not currently accessible to keyboard users. If this problem cannot be overcome then it may be necessary to use an ordinary dropdown combo list instead, like the current dropdown for Page View / Continuous View.