What does Integrated Services Digital Network (ISDN) mean?
Integrated Services Digital Network (ISDN) is a digital telephone network technology that was widely used in the voiceover and audio recording industry from the 1980s through the 2010s to transmit high-quality audio over telephone lines in real time. ISDN allowed a voice actor in one city to record a session while being directed by a producer or client in a completely different city, with near-broadcast-quality audio in both directions. Although ISDN has been largely replaced by internet-based audio transmission systems such as Source-Connect and Cleanfeed, it remains in limited use at some legacy broadcast facilities.
Example:Before internet-based audio connections became reliable, a voiceover actor in Los Angeles used an ISDN line to record a commercial session with a New York advertising agency, receiving direction in real time without either party needing to travel.
Example: The recording studio listed ISDN capability in its equipment inventory — a legacy feature still requested by some international broadcast clients who had not yet transitioned to modern IP-based audio transmission systems.
Did you know?
At its peak, an ISDN line cost studios and agencies hundreds of dollars per month in infrastructure fees, plus per-minute charges for each call. The rise of affordable, high-quality internet audio solutions like Source-Connect made ISDN economically obsolete almost overnight — and most telecom companies have now officially discontinued ISDN service.
You can also find “Integrated Services Digital Network (ISDN)” and related terms in this category: Technology and Equipment.
