(Very good answers above!) There are so many examples of music communicating more information than mere artistic expression.
The only reason that the Romans developed the brass horn was to signal troop movements. They made brass horns bigger, louder and implemented a set of musical motifs to order charge, retreat, etc. They weren't interested in music at all, but the modern-day brass section owes a debt of thanks to the Roman army. The same applies to other cultures using the drums, bagpipes, etc. The psychological warfare aspect to these noisy instruments is secondary to communication among troops.
Church bells are another ubiquitous example: signaling time, weddings, emergencies, celebrations, etc. Town bell towers indicate time, in fact Big Ben uses different variations of a melody to signal time every fifteen minutes.
In the modern era, the spacecraft Voyager included a CD recording of several great musical works, in an attempt to communicate some information about Earth to any civilization that discovers it (and succeeds at decoding it).
At my local university, I participated on a research team to create an algorithm that would synthesize an instrumental soundtrack to replace the continual beeping of the ECG. The premise was that a melody could contain several elements, each tied to a different bio-feedback item. Therefore, the overall status of a patient could be easily determined by the nurse upon his/her entering the patient's room and hearing the melody. As a side-benefit, this soothing melody replaced the annoying beep of the ECG.