73421.3.4.7 Automatic Microphone Mixers with Matrix Mixing to Multiple Outputs..................... 752
21.3.4.8 Automatic Mixing Controller....................................................... 752
21.3.4.9 Automatic Microphone Mixers Implemented in Software................................. 752
21.3.4.10 Which Type of Automatic Mixer Works Best?........................................ 754
21.3.5 Teleconferencing and Automatic Microphone Mixers........................................ 754
21.3.6 Room and Building Acoustics.......................................................... 755
21.3.6.1 Conference Room Noise........................................................... 755
21.3.6.2 Conference Room Reverberation.................................................... 756
21.3.6.3 Telephone/Transmission System Interface............................................. 757
21.3.7 Teleconferencing Equipment........................................................... 758
21.3.7.1 Telephone Interface............................................................... 758
21.3.7.2 Microphone Considerations........................................................ 759
21.3.7.3 Microphone Mixing.............................................................. 759
21.3.7.4 Loudspeaker Considerations........................................................ 759
21.3.7.5 Send Level Control............................................................... 760
21.3.7.6 Echo Canceler................................................................... 760
21.3.7.7 Historical Examples of Teleconferencing Equipment.................................... 760
21.3.7.8 The Present and Future of Teleconferencing........................................... 762
References................................................................................. 763
Patent References............................................................................ 763
Bibliography............................................................................... 763