Digital Audio Tape (
DAT or
R-DAT) is a signal recording and playback medium developed by
Sony and introduced in 1987. In appearance it is similar to a
Compact Cassette, using 3.81 mm / 0.15" (commonly referred to as 4mm)
magnetic tape enclosed in a protective shell, but is roughly half the size at 73 mm × 54 mm × 10.5 mm. As the name suggests, the recording is
digital rather than
analog. DAT has the ability to record at higher, equal or lower sampling rates than a
CD (48, 44.1 or 32
kHz sampling rate respectively) at 16
bits quantization. If a digital source is copied then the DAT will produce an exact clone, unlike other digital media such as
Digital Compact Cassette or non-
Hi-MD MiniDisc, both of which use a lossy data reduction system.