Optional ReadonlydefaultThe value the thing behind the control COMES UP AT — the fresh/reset target a surface
offers (double-click, "reset to default"), in unit.
DECLARED, never guessed: it rides only where the owner can name the value its hardware or stage actually starts from (a REAC preamp's committing normal gain, a digital stage's unity), and only where this travel can hold it. Absent means the control has no declared default and a surface offers none beyond its own convention — a default outside the travel would be a reset onto a value the control cannot reach, so it is omitted rather than clamped into a different claim.
Optional ReadonlydefaultHOW the owner knows default — present exactly where the default is, absent where it
is (GAIN_DEFAULT_PROVENANCES).
A default with no provenance is a number the desk cannot explain, and the two facts it must be able to tell apart carry the SAME number: +32 dB is a MEASUREMENT of a Roland box and also this desk's JUDGEMENT about a nominal mic gain. A surface that says "the box arms this" over the second is lying, and one that cannot say "your setting" over an operator's own override makes the operator guess whether their write took. Both are what this member answers.
It rides the LIMIT rather than a second row because it is a property of the declared travel's default and travels with it through every bridge — OPTIONS, the descriptor a widget binds, the settings page. Splitting them is how a value and its claim come to disagree.
ReadonlymaxHighest legal value, in unit.
ReadonlyminLowest legal value, in unit.
ReadonlystepThe smallest difference the thing behind the control actually resolves.
ReadonlyunitThe engineering symbol the numbers are in (do-not-translate).
The declared travel of ONE numeric control — bounds, resolution and unit together.
The four members travel as one because splitting them is how they drift: a bounds-only table leaves the step and the unit to be typed wherever the control is drawn, and a step typed at the call site is a claim about what the thing behind the control RESOLVES, made by the surface that cannot know it.
GATE_LIMITSandCOMP_LIMITScarried{ min, max }and every consumer supplied the other two by hand.This is the desk-independent case: a limit is a property of the PROCESSOR (a compressor's ratio tops out at 20:1 because of what that compressor is), so it is declared once. A travel that varies by DEVICE is the other cardinality and comes from that device's capability — see gainDescriptorOf.