You can enjoy (?) the demo at https://clock.johnwarburton.com/
This is a talking clock in Javascript. It tells the time for my home town, Lewes — which happens to sit on the Greenwich meridian.
The mechanism involves sound files loaded into a web browser, then played back at the right time.
Importantly, this is an instance of in-browser generation and instantaneous assembly of audio, synchronized to an atomic clock's timestamps served from my website.
Much that is musical can follow from this.
The project and its associated audio is covered by the GPL license, so you are welcome to repurpose it for anything provided you release your changes under these conditions.
The best fun in this project comes when you replace the given sound files (which are by me) with your own voice. The filenames in the audio/ directory show you what is required. It took me less than 30 minutes to record and edit them.