frequencies (a / friction) (2015) by Nicolas Bernier
A Letter from Schoenberg (1996) by Peter Ablinger.
Listen first to the version without text:
And listen now to the version with text added:
Wave Train (1966) by David Behrman performed by Musica Nova.
Neo Bechstein demonstration from 1933 “it is heard through the medium of a loud-speaker” (I love how she pronounces loud-speaker!).