This might be an unpopular opinion. I HATE the sound of whistling, fine in a song done professionally but other than that I can't stand it.

@SW-User I listen to the quartet many times, until I feel I've understood the "spirit" of the music. Then I'm able to whistle it. It's like playing it with my lips.
At the moment I'm learning "String Quartet No. 2 in D-flat major, Op. 15" by Ernő Dohnányi.

@helenS A good approach, and I do love music. I don't listen to a lot of classical, but I do happen to love Bobby McFerrin whose art is often taking classical music, sing it acapella. This should demonstrate the power of voice

[media=https://youtu.be/ne6tB2KiZuk]

@SW-User I love that guy. He's a genius. Have you listened to "The Mozart Sessions"? With Chick Corea, and a Chamber Orchestra..
Here's their "Song for Amadeus":
[media=https://youtu.be/NNfrvsWNHcA]
Enjoy! 🌷

@WintaTheAngle ... whistling a Disney tune, of course... 😏