The most common and most likely answer to this crossword clue is the 9 letter word AUDITORIA
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result AUDITORIA
- Where some may hear a posh leader endlessly
- Where listeners sit, check old song over
- Song embracing nakedness – having no clothes, nothing – may be heard here
- One perusing books and article about Italy’s theatres
- Where one may hear tenor interrupting Carmen by second half of aria
- Examiner overturning top mark in halls
- Check on old artist touring independent theatres
- Houses vet next to old unfinished Moroccan palace
- Song about it duo ruined in concert halls
- Places where some are dazzled and most are kept in the dark?
Buddy explains!

The straight part
We know that "Places where some are dazzled and most are kept in the dark" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case places where some are dazzled and most are kept in the dark = auditoria.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 AUDITORIA mean?
AUDITORIA noun- A large room for public meetings or performances.
- (in a theater, etc.) The space where the audience is located.