touch@grad2.cis.upenn.edu (Joseph D. Touch) (03/07/91)
I forgot to mention that the notion that samples come off the CD serially is bogus too. CD samples are chunked into groups, and block encoding is done on them (Reed-Solomon). When a block is read off the disk (serially), the WHOLE BLOCK goes into memory and gets decoded. The only problem is the bandwidth between memory where the decoded block is stored and the D/A's - if the data path supports reading only one channel out at a time, then it is serial, regardless of how many D/A's you have. It'd be a better selling point to say "dual D/A converters with a 24-bit wide memory" (assuming samples are 12 bits, which I don't recall). In fact, using dual D/A's permits using SLOWER D/A's, and I wasn't aware that 88.4 kilosamples/sec was all that fast (if a single one were used). Joe Touch PhD Candidate Dept of Computer and Information Science University of Pennsylvania