As for the sonification, a star's convection produces waves that correspond to different sounds.

 The team adopted a similar strategy, running short simulations of waves generated by convection and recording the waves as they moved beyond the convection zone. First, they built a model to calculate the basic "song" of those convection waves—technically, the photometric variability from the gravity waves—and then they applied a filter to replicate the star's acoustical properties, akin to the damping filters used in a recording studio. Once this approach had been validated, Anders et al. ran convection simulations for stars with masses of three, 15, and 40 times our Sun. These showed what those waves should look like when viewed through a telescope.

 “The smaller stars in our study are more like the violin, where they have some more high-pitched noises because they have a smaller wave cavity, just like a violin has a smaller wave cavity,” Anders told New Scientist. “And our larger stars have a bigger wave cavity, just like a cello has a bigger wave cavity, so they have some deeper noises.” They used their model to find out what a song would sound like if we heard to propagated through a star by applying it to real music. "The stars change the music and, correspondingly, change how the waves would look if we saw them twinkling on the star's surface," said Anders.

The simulations also revealed that the twinkling attributable to core convection is simply too weak to fully explain the observed red noise effect in massive stars. It's possible that convection nearer to the star's surface could account for the red noise, but according to co-author Matteo Cantiello of the Flatiron Institute's Center for Computational Astrophysics in New York, this would tell astronomers less about the processes occurring deep in the star's interior. The next step is to improve their simulations to take other effects into account, such as a star spinning rapidly around its axis, which might produce a flickering strong enough to be detected by telescopes.