Answer: gclefs

AnswerCrossword Clue
GCLEFS

Staff leaders?

GCLEFS

Features of top-level staffs

GCLEFS

Scoring leaders?

GCLEFS
Heads of staff?
GCLEFS
They may be put on the staff
GCLEFSSigns of treble
GCLEFSTreble symbols
GCLEFSSymbols near key signatures