The most common and most likely answer to this crossword clue is the 7 letter word TYMPANA
I've seen this crossword clue in Independent
T
Y
M
P
A
N
A
Buddy explains!
The straight part
We know that "instruments" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case instruments = tympana.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 TYMPANA mean?
TYMPANA noun- A triangular space between the sides of a pediment.
- The space within an arch, and above a lintel or a subordinate arch, spanning the opening below the arch.
- The middle ear.
- The eardrum.
- A hearing organ in frogs, toads and some insects.
- In certain birds, the labyrinth at the bottom of the windpipe.
- A drum-shaped wheel with spirally curved partitions by which water is raised to the axis when the wheel revolves with the lower part of the circumference submerged; used for raising water, as for irrigation.