Hi Mark,

This is a technique that's been used for creating music for centuries. The most famous creation I know is Rachmaninoff's 18th variation on a theme by Paganinni.

The theory behind how this was created using negative melody is below.

While Paganinni inspired Rachmaninoff's creation, he didn't write it. The melody and harmony are quite different.

Audiophile BIAB 2024