The puzzle answers, and the instruments associated with the puzzles, are as follows:
Handbells: BELLADONNA Flute: CRESCENDOS Celesta: BACKSOLVER Drum kit: ACTAPILATI Double bass: FAMILYNAME
The puzzle answers contain as substrings the names of the solfege syllables, DO RE MI FA SOL LA TI. (Each answer contains two solfege syllables except BACKSOLVER, which contains the only three-letter solfege syllable.)
Moreover, all the puzzle answers are the same length, and each solfege syllable is at a unique position in the word: the FA in FAMILYNAME is in first position, the RE in CRESCENDOS is in second position, and so on. Convert the solfege syllables into the corresponding scale degrees 1 2 3 4 5 6 7, and you get this:
Celesta: 5 Drum kit: 6 7 Double bass: 4 3 Flute: 2 1 Handbells: 6 1
From left to right, index into the instrument names by the scale degrees. This spells out BLUE SHIFT, which is the answer to the metapuzzle.