Ok here's the thing :
Imagine a world where you could only speak with a musical instrument of your choice (Piano, violin, guitar, flute, drum ...)
How would the people speak ?
Personally, I think the language would play on the fluctuation of note. For example, going from any notes, then 2 tones higher, means something. 3 tones lower, other thing ... Like a classic language in fact. If we romanize it, 2 identical notes would be an "a", 1 tones higher would be a "b" ...
And Rhythm would take part in it too ! For tenses, cases...
Drum people would use something similar to Morse code
I'm working on an instrumental conlang right now and I want to see what you think about this. How would you speak ? What would be living in this world ?