The most common and most likely answer to this crossword clue is the 9 letter word ORCHESTRA
I've seen this crossword clue in Independent
O
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More clues leading to the result ORCHESTRA
- Actors improvised with her players
- Revolutionary way Gunners pursue ends of other players
- Her co-star played in a musical group
- Soldiers box artist and players in pit
- Players endlessly dart around outside the box
- Big band has rector dancing
- New RH briefly needs time in stalls in US
- . Her actors retrained as musicians
- ‘Players‘ – men – start to charm broken hearts
- Gold box used by painters and pit workers?
Buddy explains!

The straight part
We know that "A band" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a band = orchestra.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.
What does ORCHESTRA mean?
ORCHESTRA noun- A large group of musicians who play together on various instruments, usually including some from strings, woodwind, brass and/or percussion; the instruments played by such a group.
- A semicircular space in front of the stage used by the chorus in Ancient Greek and Hellenistic theatres.
- The area in a theatre or concert hall where the musicians sit, immediately in front of and below the stage, sometimes (also) used by other performers.