AM Stereo - Current Status

Current Status

Globally, interest in and use of AM stereo has been declining steadily since the 1990s, as many music stations have continued to move to the FM band. As a result, the vast majority of AM stations broadcast News/Talk or Sports/Sports Talk formats. Many of the stations that initially implemented AM stereo are clear-channel 50,000 watt stations, and are more concerned with listening range than stereo sound (although there is no proof that use of AM stereo affects listening range). As a result, these stations still have the necessary equipment to broadcast in stereo, but it is left unused (or converted to HD Radio). Also, many former AM stereo stations were bought up by broadcasting conglomerates, which generally discourage AM stereo broadcasting. In the United States, most stations currently using AM stereo are small, independently owned and broadcast a variety or music format.

• Japan: Between 1992 and 1996, 16 commercial broadcasting companies in Japan adopted C-QUAM because of the narrow Japanese FM band; it covers only 14 MHz (76-90 MHz), as opposed to the 20.5 MHz used in the rest of the world (87.5-108 MHz). However, it is now quite rare to see AM radios with stereo the function at appliance stores in Japan because of the decline in AM stereo stations and the limited available area, mainly in densely populated areas. 12 of the 16 stereo stations have since reverted to mono, 10 since the start of 2010 (ja:AMステレオ放送), leaving only 4 stations broadcasting in stereo.
• Australia: AM stereo was popular in Australia because AM covers a wide geographic area compared to FM, in addition to the government's adoption of a single standard (Motorola C-QUAM) several years sooner than the USA, and Australia's relatively late adoption of FM (the frequencies in the FM band were originally allocated for TV). As of June 2008 no Melbourne AM stations broadcast C-QUAM AM stereo. At its peak popularity in the late 1980s the majority of stations did.
• Europe: After some experiments in the 1980s, AM stereo was deemed to be unsuitable for the crowded band conditions and narrow bandwidths associated with AM broadcasting in Europe. However, Motorola C-QUAM AM stereo remains in use today on a handful of stations in France, Italy, and Greece.
• Canada: AM stereo was more widely adopted in Canada than in the USA. This may have been due to the Canadian government's decision to use a single standard, and the Canadian Radio-television and Telecommunications Commission (CRTC) licensing stations by format and their hit/non-hit rules for FM (hence, more music stations on AM). However, unlike in the USA, some former AM stereo stations have moved to the FM band and left the AM band altogether instead of simply reverting to mono.