The intercom system for the Madonna Confessions tour began with a combination of Telex BTR800 and HME Pro850 intercom systems, each of which used six frequencies.  The UHF spectrum for wireless mics and ear monitors, along with the intercom, approached 90 frequencies. In today's whitespace-crowded world, this system could not work.

 
Madonna, The Confessions Tour, graphics.

Madonna, The Confessions Tour, graphics.

Eighth Day Sound, the audio contractor for the Madonna Confessions tour, called Larry Estrin to help. Estrin replaced the five UHF wireless intercoms with three HME DX200 systems. Most of the beltpacks were fitted with David Clark’s headsets and noise-cancelling mics. This system freed up thirty UHF frequencies and worked without fail across the country.