The impact that wiped out the dinosaurs also wiped out all songbirds, except for in (ark) Australia. Australian songbirds then spread out to rest of the planet.
The closest living descendents (aka basal lineages) are the Lyrebird and the Rufus scrub bird. The lyrebird’s song is a mixture of its own song and other birds songs. They have been also been known to mimic chainsaws, car alarms, camera shutters, and human speech.
Australia has song birds about the size of a crow, they’re called Magpies. They are at times aggressively territorial, extremely intelligent, family orientated and very pleasant to wake up to in the morning.
Occasionally silly https://m.youtube.com/watch?v=hu3hrXjMtNI
Occasionally terrifying https://m.youtube.com/watch?v=EXYf2DTOsvI
Song at 1:23 of the second video.
Yeah, like that, but with constant song bird singing.