Ah, c'est Ray!​

For many years, I have been writing to a pen-pal in France. In his latest letter, he said that he had something to give me so we should meet in person. I knew that Laurent dabbled in some composing for the violin, so it wasn’t surprising that when we met, he gave me some sheet music with some notes at the bottom:

lowercase = [4, 9, 10, 13, 16, 17, 24, 28, 29, 31, 32, 33, 34, 35, 36, 37, 40, 43, 44, 45, 47, 48, 50, 52, 53, 56, 57, 59, 60, 62, 65, 66, 68, 69, 70, 73, 76, 78, 80, 81, 84]

_{^{Transcript:
treble clef qf wf wf+ qb qa+ qa ef wd ef qg+ ef wd ed ec qc ec eg ec wf+ wg qa+ qf+ ee+ ec qg+ qf+ qf ec ee qe+ ea+ eg+ ee eb+ ea+ qc ed ed+ qf qc ee+ ea eg+ qc ee ec qe+ ec qg+ eb+ qc ec eg wf eb qe eg ec ea+ qc qa+ qg+ ee we ee eb+ qg ea+ ef ee+ ee wd ed ec qc ec qg+ eb+ qd+ qa ee ed+ eb+ qc
q = quarter; w = whole; e = eighth; + = upper octave}}

What I did find odd was that when he saw me at the airport, he said "Ah, c’est Ray!" and gave me the music, though for several years I have been signing my letters with "Sincerely, Gary."

Now that I’ve had some time (what with quarantine and all), I pulled out my violin and played through this passage… but something’s off about it. Then, I realized that Laurent probably hid a secret message in the music. Classic Laurent!

Your mission, should you choose to accept it, is to find the message. When you do, tell me what Laurent wishes me to know.

Hint 1:

Hint 2:

Hint 3: