The "croaking" reversing alarm is the white-noise or broadband type, and are considered to be an improvement. https://en.wikipedia.org/wiki/Back-up_beeper http

The "croaking" reversing alarm is the white-noise or broadband type, and are considered to be an improvement. https://en.wikipedia.org/wiki/Back-up_beeper https://en.wikipedia.org/wiki/Back-up_beeper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3018517/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3018517/ "Still another alternative is the broadband beeper, a device that has the same cadence as the conventional beeper but broadcasts a “white-noise, whooshing sound,” says Thalheimer, who has no financial interest in or affiliation with Brigade Electronics, the manufacturer. He explains the sound is still readily audible behind the vehicle and is more easily localizable than a single-tone beeper, but the white noise is masked by community noise, so it is much less annoying to the public." https://www.forconstructionpros.com/construction-technology/construction-safety-technology/news/21138262/world-of-concrete-white-noise-backup-alarms-improve-safety https://www.forconstructionpros.com/construction-technology/... https://brigade-electronics.com/en-us/products/backup-and-warning-alarms/ https://brigade-electronics.com/en-us/products/backup-and-wa...