Music on hold

Music on hold (MOH) is the business practice of playing recorded music to fill the silence that would be heard by telephone callers who have been placed on hold. It is especially common in situations involving customer service.

Music on hold is sometimes referred to as phone on hold, message on hold, on hold messaging, hold music, etc.

Music on hold was created by Alfred Levy, an inventor, factory owner, and entrepreneur. In 1962, Levy discovered a problem with the phone lines at his factory. He discovered that a loose wire was touching a metal girder on the building. This made the building a giant receiver so that the audio broadcast signal from a radio station next door would transmit through the loose wire and could be heard when calls were put on hold. Levy patented his work in 1966. While other advancements have come to change and enhance the technology, it was this initial patent creation that began the evolution for today's music on hold.

Most MOH systems are integrated into a telephone system designed for businesses via an audio jack on the telephone equipment labeled "MOH". There are also some units with built-in message on hold capabilities and units designed for small businesses without an extensive phone system.

Music and messages on hold are played using either physical or virtual media.

Today, equipment that supports physical media usually plays CDs. Some older systems may still use cassette tapes (sometimes employing endless-loops), or reel-to-reel tape players. In each case, the unit loads the media into a digital memory chip to prevent premature wearing of the mechanical parts.

Equipment that supports virtual media generally plays MP3 files. Several types of units play these files. USB Flash Drive units allow an MP3 file to be received electronically, downloaded to a flash drive and connected to the player. Ethernet based remote load units connect via the network to a remote IP address. Phone line based remote load systems allow for a connection via an analog telephone line and dialing the number belonging to the unit. For phone systems, MP3s are loaded without any equipment.

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Wikipedia