Hi

I think a simple LM3915 or 3916 could do most of the job, offering moreover a superb "christmas tree " ... to your child's eyes.

just select the open collector output for the level to trigger!!!

National datas offer the drawings for full wave rectification, averaging, peak detection ... Heaven !!!

No, Analog circuits are not dead ...

Alain

PS : France : 1 point ... Canada : Boooooo....