A group of unconventional musicians is getting ready to crank out the tunes at Riverside Park in Ypsilanti. Literally. More than a dozen owners of antique band organs are making their way to the park for the 34th annual Mid-American Band Organ Rally, which takes place on Friday and Saturday.

As the name indicates, band organs are hand-cranked pipe organs that play pre-programmed music replicating the sounds of many different instruments at once. “These are organs that you would find in an old-fashioned skating rink, before they had deejays, or in a carousel,” said Dale Dohler, who organized this year's rally with his wife, Janet. “Picture the music-making machine in the middle of a carousel and you get the idea.”

Watch this video from the 2009 Masham Steam Engine & Fair Organ Rally, held earlier this month in the United Kingdom:

Most of the band organs that will be part of this year’s rally — held in Ypsilanti for the first time ever — are from the early 19th century, but one is newly built by Ohio-based specialty company Stinson. In addition to the large organs, which have to be towed in specially made trailers, the rally will feature dozens of smaller, so-called “monkey organs,” better known as the pole-mounted instruments cranked by organ grinders. “The band organs will be located around Riverside Park, but the monkey organs are more portable, so their owners will take them all around through Depot Town,” said Dohler, who will have his own monkey organ at the park for demonstrations. He said most band organ owners are eager to show off their unusual instruments and many are happy to allow interested spectators the opportunity to try them out for themselves. “It’s a great opportunity to talk, listen and crank,” he said. You wouldn’t believe how happy these instruments make people.”

The event runs 10 a.m.-5 p.m. Friday and Saturday in Riverside Park, near Cross and Huron streets, and Depot Town, in Ypsilanti. Admission is free.