The most common and most likely answer to this crossword clue is the 12 letter word CIRCUMSTANCE
I've seen this crossword clue in The Daily Telegraph
C
I
R
C
U
M
S
T
A
N
C
E
Buddy explains!
The straight part
We know that "Something associated with the pomp of a final musical performance?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something associated with the pomp of a final musical performance? = circumstance.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 CIRCUMSTANCE mean?
CIRCUMSTANCE noun- That which attends, or relates to, or in some way affects, a fact or event; an attendant thing or state of things.
- An event; a fact; a particular incident.
- Circumlocution; detail.
- Condition in regard to worldly estate; state of property; situation; surroundings.
- To place in a particular situation, especially with regard to money or other resources.