This excerpt taken from the SIRI 10-K filed Mar 16, 2005.
National Broadcast Studio
Our programming principally originates from our national broadcast studio in New York City. The national broadcast studio houses our corporate headquarters, our music library, facilities for programming origination, programming personnel and facilities to transmit programming to our orbiting satellites. We also originate some of our programming from small studio facilities in Houston, Texas; Memphis, Tennessee; Nashville, Tennessee; and Los Angeles, California.
The studios and transmission facilities at our national broadcast studio are 100% digital, resulting in no cumulative distortion to degrade the sound of our music and entertainment product. The national broadcast studio also contains state-of-the-art production facilities. Service commands to initiate and suspend subscriber service also are relayed from our national broadcast studio to our satellites for retransmission to subscribers' radios.