Every weekday at noon in Ann Arbor there's a live concert taking place 10 stories above the students who hustle to get to their classes on time.

The concert is played on one of University of Michigan's most valuable instruments, the Charles Bard Carillon, which includes 53 bells that sit 212 feet high, perched at the top of the Burton Memorial Tower on central campus.

The largest bell weighs 24,000 pounds and the entire collection clocks in at 45 tons.

The carillon, acquired by the university in 1936, is one of roughly 200 active carillons in the world, and one of the largest and most valuable among them.

U-M's carillon program dates back to 1939 and, according to program director Steven Ball, is the oldest carillon program in the U.S. Every year between 15 to 20 students study the art of the carillon under Ball, who has been playing the carillon for 18 years.

"It has this sort of dark, smokey sound that's very special," said Ball, who called the carillon a "civic instrument" that plays "at the pleasure of the regents."

It's Ball, U-M alumni and students who make the daily carillon concerts possible.

Unlike the automated ringing of the bells every 15 minutes, the noon concert takes considerable man power. Everyday, a carillonneur plays a unique 30-minute noon concert that's audible "for a couple of blocks" surrounding the bell tower.

The carillonneur, or a counterpart, then travels to north campus to give another concert there, at the Ann and Robert H. Lurie Carillon and Tower.

The system could be automated, but then the university would lose one of its richest and longest traditions.

"You don't have the ability to make an automative system expressive. There's a certain continuity with the life and the culture of this place that would be lost," Ball said. "Selections change day-to-day and they generally try to fit the mood of the occasion."

He added: "The bells mark moments in university time."

The concerts take place during days when classes are in session. According to Ball, the only time the concerts have been unexpectedly halted since the 1930s is when a pair of Peregrine falcons was found nesting on the tower in 2006. After about a month, when the falcons were deemed safe, the bells resumed ringing.

Anyone can attend the performances.

Ball said the carillon is the largest unaltered British-made system of its kind in the world. In the 1970s, the university replaced about half of the bells in the carillon in order to make the instrument louder and have a wider range, but in the mid-2000s Ball collected the old parts and restored the carillon to its original condition, despite the objections of some colleagues.

"It's always the same thing in our culture: faster, louder, brighter, shinier," Ball said. "The reality is that, historically, this carillon occupies such a significant place in North America.... Returning the bells, returning the keyboard, it really returns the sound of the instrument back to what it was."

Kellie Woodhouse covers higher education for AnnArbor.com. Reach her at kelliewoodhouse@annarbor.com or 734-623-4602 and follow her on twitter.