telephony

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Hold music used to sound better. Here's why.

Hold music used to sound better. Here's why.

2.9M views • 8 years ago

Tom Scott explains why hold music sounds worse than it used to, tracing it to old telephone exchanges and the audio compression applied by modern switches. It is a short visit to the Milton Keynes Museum.

AT&T Archives: The Step-By-Step Switch

AT&T Archives: The Step-By-Step Switch

774K views • 15 years ago

AT&T Tech Channel

A 1951 Bell System training film showing how telephone calls are routed through a step-by-step (Strowger) switching office.