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Apparently Dolby uses a "locally linear" type like the standard audio compressor. I'm learning more about it... - Omegatron 19:03, Feb 8, 2005 (UTC)

Companding and digital compression (data reduction) are not the same thing!

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Removed the following irrelevant (and uncited) text from the article:

"Many of the music equipment manufacturers (Roland, Yamaha, Korg) used companding for data compression in their digital synthesizers. This dates back to the late 1980s when memory chips would often come as one of the most costly parts in the instrument. Manufacturers usually express the amount of memory as it is in the compressed form. i.e. 24MB waveform ROM in Korg Trinity is actually 48MB of data. Still the fact remains that the unit has a 24MB physical ROM. In the example of Roland SR-JV expansion boards, they usually advertised them as 8MB boards which contain '16MB-equivalent content'. Careless copying of the info and omitting the part that stated "equivalent" can often lead to confusion."

Reducing the number of bits to fit within a smaller storage device is (obviously) data reduction (also popularly referred to as "compression"), not to be confused with dynamic range reduction, which is what the "comp" in "companding" refers to. — Preceding unsigned comment added by 97.115.32.222 (talk) 21:12, 28 May 2012 (UTC)[reply]

That is actually companding. Companding is a method of data compression because compression reduces the number of bits needed to store a signal digitally. Compress the dynamic range of the input signal for transfer, then expand it for output. Compansion is better than quantization because it retains greater S/N for low-level signals. Removing the paragraph for being uncited is reasonable, but that is a form of compansion and the distinction you are thinking of is actually irrelevant here. Compansion compresses data by compressing dynamic range. Radiodef (talk) 18:18, 8 November 2012 (UTC)[reply]