https://www.birds-of-north-america.net/Peregrine_Falcon_songs_and_calls.html
Peregrine Falcon Songs and Calls (Falco peregrinus)
The North American Falcons.
songs and callsperegrine falcon
https://www.birds-of-north-america.net/Black-capped_Chickadee_songs_and_calls.html
Black-capped Chickadee Songs and Calls (Poecile atricapillus)
The North American Chickadees.
black capped chickadeesongs and calls
https://www.birdnote.org/podcasts/birdnote-daily/birding-101-songs-and-calls
Birding 101: Songs and Calls | BirdNote
Learning the difference will make you a better birder!
songs and callsbirdingbirdnote