Dial-up audio for outside broadcasts and remote events

With the rapid move towards a `tapeless' environment the professional audio industry, and that includes broadcasting, is continually seeking ways to adapt digital technology for high quality audio. The technique of compressing digital audio and the ability to dial-up, on demand, a high quality audio circuit, defining the bandwidth limits, be it for speech or music, mono or stereo, has very clear economical and practical advantages for potential users. Developments in bit rate reduction and the increasingly available ISDN network, both nationally and internationally, have the potential to alleviate many of the problems associated with traditional analogue circuits. The author discusses the use of ISDN for audio broadcasts and the compression of the audio signal. Codec selection and compatibility are also discussed.