I'm looking for something that I can run in the terminal that will give me a VU readout of the loudness of the left and right channels of the built-in input.

Any suggestions?

(this is for my college Radio station, and I want to build a cron task that checks for dead air every 10 min. Ultimately, i'm hoping to be able to determine whether or not silence is being broadcast, and if it is, I want to be able to send a simple GET http request to the server at chapmanradio.com)