ampling rate and 2 X 16- bit codewords (the factor of two being for stereo-effect purposes). To recall, PCM is an uncompressed, lossless code, which yields maximum sound quality (referred to as CD-quality) for professionals or audiophiles, but necessarily comes with relatively large sizes for the digital-audio files. Microsoft and IBM have adapted this uncompressed- PCM audio codec for use in home computers, under the brand name WAV (short for 8 See, for instance: http://en.wikipedia.org/wiki/Eight-to-Fourteen_Modulation. 9 See, for instance: www.physics.udel.edu/~watson/scen103/efm.html, See, for instance: http://en.wikipedia.org/wiki/A-law_algorithm. http://en.wikipedia.org/wiki/Compact_disk; http://searchstorage.techtarget.com/sDefinition/0,,sid5_ gci503642,00.html; www.answers.com/topic/compact-disc-2. Appendix G waveform). The data are recognized by the .wav filename extension. Any audio file can be compressed using lossy codecs, typically up to an 80% compression rate, 12 with the original sound quality being lost forever, yet producing acceptable sound restitution, depending on the music, audience, and utilization. See further on for this topic. In contrast, lossless audio compression fully preserves the original CD quality. Two key examples of lossless compression codes that can be used for music are the popular ZIP (see further), which can achieve 10-20% compression, and FLAC (short for free lossless audio codec), which can achieve over 40% compression. 13 In short, FLAC is based two algorithms: linear predictive coding (LPC) 14 and run-length encoding (RLE). first makes it possible to decompose acoustic spectra into a reduced list of parameters, which in the reverse implementation can faithfully reproduce the original sounds. Linear predictive coding was originally developed for speech analysis, low bit-rate compression and re-synthesis. Key applications of LPC include cellular telephony (GSM), speech recognition, and electronically synthesized music. The principle of RLE is to replace sequences of repe