The most common and most likely answer to this crossword clue is the 6 plus 4 letter word TREBLE CLEF
I've seen this crossword clue in The Guardian
T
R
E
B
L
E
C
L
E
F
More clues leading to the result TREBLE CLEF
- Sign on staff — 300 nearly departed
- More than double more or less divided the sign of high scorers?
- Music character around clubs left rebel in Dire Straits
- Flat pitch – triple century left unfnished
- In short, County Cricket Club departed abruptly heading for bar
- Musical character felt laid back about awkward celeb on right
- Character in front of the bars at the Albert Hall in summer?
- Refurbished cell bereft of staff sign
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.