This week’s tech column, courtesy of Tribune Newspapers:
Play it again, SACD. The ill-fated high-resolution audio disc is back, or at least its technology, as music downloads requiring special playback equipment.
Technology. DSD, or Direct Stream Digital, was developed by Sony (with Philips) to archive the company’s music catalog, then introduced to the consumer in 1999 as the Super Audio CD format that promised higher resolution and greater storage capacity than the CD.
A CD stores audio information using Pulse Code Modulation encoding in 16-bit samples taken 44,100 times per second. DSD, meanwhile, takes a continuous 1-bit stream at 2.8 million samples per second — 64 times the CD’s rate.
Just as more pixels produce a higher-resolution HDTV picture, more audio samples produce a higher-resolution sound.