One type of dubbing device combines two different storage media, such as an audio cassette deck that incorporates a Compact Disc recorder. Such a device enables the transfer of audio programs from an obsolete medium to a widely used medium.
Another type of dubbing device is designed to rapidly produce many copies of a program. It may combine a single playback unit with multiple recording units to simultaneously create two, four, eight, sixteen, or more copies during the playback of a single original program. This type of device can often perform the copying process at many times the standard playback speed. Typical multiplexed dubbing decks of either analog (cassette) or digital (CD) programs can operate at 48 times the standard playback speed, thus producing complete copies of a program in sixty or ninety seconds.
The verb "dub" as used here long predates and is unrelated to the Jamaican musical style dub music; the origin of both words stems from the dubplate. It is also different with the term dubbing, which is mostly a type of frottage dance usually found in the Caribbean clubs.