The most common and most likely answer to this crossword clue is the 9 letter word KEYBOARDS
I've seen this crossword clue in The Guardian
K
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More clues leading to the result KEYBOARDS
Buddy explains!
The straight part
We know that "these instruments" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case these instruments = keyboards.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 KEYBOARDS mean?
KEYBOARDS noun- (etc.) A set of keys used to operate a typewriter, computer etc.
- A component of many instruments including the piano, organ, and harpsichord consisting of usually black and white keys that cause different tones to be produced when struck.
- A device with keys of a musical keyboard, used to control electronic sound-producing devices which may be built into or separate from the keyboard device.
- To type on a computer keyboard.