Check the listing for details. Telos Zephyr 9202 Layer III Digital Network Audio Transceiver. Condition: Used. Listed at 220.00 USD. Included: Telos Zephyr Stereo 9202 Layer II + III Portable Rack Box with CD Player and Two front mounted Red & Black Speaker Terminal Binding Speaker Plugs Carrying Case Powered on. Removed from corporate work environment. Refer to Images. Telos Zephyr Stereo 9202 Layer II + III Zephyr makes transmitting CD-quality audio as easy as sending a fax. Integrating the most advanced audio coding and digital telephone technologies in a single unit, Zephyr is the perfect choice for news, sports, music, and production. On just one ISDN circuit, Zephyr can transmit two-way, 20kHz stereo audio plus ancillary data virtually anywhere in the world. It can transmit 20kHz mono audio using only one of the ISDN lines two channels. No other telephone-based system provides Zephyrs full bandwidth with equal quality and economy in both stereo and mono. To code the audio signals for transmission, Zephyr uses ISO/MPEG Layer III. International listening tests and the satisfaction of thousands of users certify that Layer III is best for ISDN. With the vast majority of program material, the coded/decoded audio can not be distinguished from the source. Telos Zephyr pioneered the use of this increasingly popular mode. In addition to Layer III, Zephyr also incorporates the ISO/MPEG Layer II and G.722 coding methods. Coding on the transmit and receive paths can be independently selected from the three offered methods to achieve compatibility and performance appropriate to your application.