high definition compatible digital (HDCD)

High Definition Compatible Digital (HDCD) is a recording process for audio CDs with a sampling depth of 24 bits and a sampling rate of 176.4 kHz with subsequent data compression.

The HDCD process, which is compatible with the 16-bit and 44.1 kHz of compact discs, is characterized by a significantly improved sound image compared to the pulse code modulation normally used, which no longer differs from the original after decoding. Playback in HDCD quality, however, requires a CD player with an HDCD processor.