Classical 24 is a syndicated, satellite-delivered public radio service providing classical music to its carrying stations. It generally airs overnights on many non-commercial and a handful of commercial classical music stations. However, the service is operated 24 hours a day and is used by some stations during the day to augment their schedules. It was co-created by a partnership between Minnesota Public Radio and Public Radio International to fulfill the need for a comprehensive classic music service for stations to supplement their schedules. As part of this partnership, the service is produced by American Public Media and distributed by Public Radio International. It began operation on December 1, 1995.
Unlike most mainstream classical music stations, Classical 24 adheres to a "clock" that typically consists of one or two short selections at the beginning of the hour, followed by a longer work such as a symphony, and then a short piece or two to close the hour. A brief pre-recorded "sound bite" interview with the composer, conductor or soloist of the next piece is sometimes played immediately prior to the piece, as an introduction.
Classical 24 also requires two breaks per hour during the day (one per hour during the overnight Music Through the Night component) and a mandatory break at the top of the hour for announcements and station identification. The service also has a six-minute "cutaway" at the top of the hour during the day for subscribers to air news programming (in many cases the standard National Public Radio newscast, as a few NPR member stations use Classical 24); this time is filled with a short musical selection for affiliates who choose not to run a newscast.
Classical 24 employs live hosts instead of using voice tracking. To make the sound as "local" as possible, there are no identifications given to the listener that they are listening to Classical 24. Only the host's name is given. For stations to automate breaks, a special decoder must be purchased and used.
In 2000, the Minneapolis Star Tribune reported that the average selection on Classical 24 was 9.5 minutes, in contrast to then rival WCAL's average selection length of 15 minutes.
Minnesota Public Radio's FM flagship station for classical music, KSJN in Minneapolis, currently offers a full-time Classical 24 feed on its HD2 subchannel. WNIU, broadcasting from Northern Illinois University in DeKalb, Illinois, is another full power FM that carries Classical 24 on a full-time basis. After November 2013, KUHA (now KXNG) in Houston (broadcasting from the University of Houston at the time) carried Classical 24 for a significantly increased portion of its schedule after discontinuing the use of local hosts during the daytime hours.