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Travis said: >All compression, analog or digital, represents a loss of information. >All professional recordings are compressed in several ways before the >final product reaches the consumer. Despite this, music still finds its >way into the world. I don't actually care very much about this particular debate, but this sounded a little confused. I suspect you're not actually confused, but anyway: The kind of compression appearing in all those professional recordings is dynamic compression, normally inflicted by a box called a compressor. Usually rather useful. This is totally different from the sort of compression talked about with MiniDisc technology. That is data compression, which is used to squeeze the digitally encoded data into a smaller space. Data compression comes in two basic flavors, lossless and "lossy." With the lossless type, as you would expect, you compress it into a smaller space, and then decompress it and you get exactly the same data you started with. You can only compress things so far this way. Lossy compression, which MD uses, takes advantage of deficiencies in human senses. With audio, your ears are not very good at hearing certain parts of a complex audio waveform. "Masking" for example, is a phenomenon where a dominant frequency will prevent you from hearing slightly higher frequencies. Lossy compression algorithms look for these situations and remove them from the audio, which allows the data to be compressed much smaller. The idea is that it is removing parts you can't hear anyway, to aid in the compression. When you decompress it, those parts are gone. You can take this to various extremes to achieve greater amounts of compression. As you achieve higher data compression ratios, the quality of the audio continues to degrade and becomes increasingly noticeable to the listener. I would imagine that MD is well below the point where most people would notice. On the other hand, anybody can hear the degradation in a RealAudio file encoded for a 28.8 modem rate. This sort of compression is also done in the very cheap samplers out from Boss and Yamaha. Whether you care about this, is of course up to you. kim ______________________________________________________________________ Kim Flint | Looper's Delight kflint@annihilist.com | http://www.annihilist.com/loop/loop.html http://www.annihilist.com/ | Loopers-Delight-request@annihilist.com