Kepler thought each planet sings one interval: the ratio between its slowest and fastest motion around the Sun. Four centuries later the orbits still bear most of him out. Press play and listen.
A planet moves fastest at perihelion and slowest at aphelion. Seen from the Sun, the ratio of those two speeds is ((1+e)/(1−e))², where e is the orbit's eccentricity. Kepler had no such formula yet; he got his intervals from Tycho Brahe's observations and named them in music.
Each shaded wedge is swept in one twelfth of the selected planet's year. Near the Sun they are short and wide, far out long and thin, yet every wedge has the same area. That is Kepler's second law, and it is why the pitch slides.
Some systems lock their orbits into small whole-number ratios. Pitch here is proportional to orbital frequency, so a 3:2 resonance sounds as a perfect fifth and 2:1 as an octave. Each body plucks once per orbit as it crosses the top of the dial.
Orbital elements are J2000 mean values; planet positions start at the real date in the readout. Resonant chains start lined up, which real systems are not. Pitches are transposed into hearing range, as Kepler also did.