The face of in-car entertainment likely will change forever beginning Sept. 12, when XM Satellite Radio begins broadcasting 100 channels of commercial-free music, news, talk and sports to vehicles on the road.

The historic broadcast will originate at XM Satellite Radio's headquarters and broadcast studio complex in Washington, DC.

Only drivers of certain Cadillac models in Dallas/Fort Worth and in San Diego will be able to hear the first XM Satellite Radio broadcast, but GM and other manufacturers will be installing the receiving equipment on several future model year vehicles.

XM will expand its launch in mid-October to the entire Southwest. The company hopes to be make its services available nationally by Christmas, the high point for consumer electronics sales.

XM's 100-channel lineup will feature 71 music channels, more than 30 commercial free; and 29 news, talk, sports and entertainment channels.

Consumers, either via dealers or other retail outlets, can purchase the special receiver and antenna for between $249 and $299. The monthly subscription rate is $9.99.

The tuner is a black box about the size of a paperback novel that is installed in the trunk and the antenna is a small roof- or window-mounted arrangement.

XM Satellite Radio is the fruit of a several-year effort to beam programming into vehicles. The network consists of the broadcast center in Washington, two Boeing 702 satellites in geostationary orbit and more than 1,000 terrestrial repeaters located throughout the continental US.

The company digitizes the programming, beams it to the satellites. The terrestrial repeaters ensure satellite coverage in areas with tall buildings and other obstructions.

Pioneer, Alpine and Sony manufacture receivers that include chipsets that decode signals from the satellites and repeaters.