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Trevor Trevor is offline
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Default LAME conversion to MP3

On 22/02/2020 4:33 am, Scott Dorsey wrote:
wrote:

You are correct. The file uses ADPCM compression, I believe, so it is
not CD quality. It uses a bit depth of 4 bits, which is de-compressed
when playing to 16 bit.


ADPCM is not lossy compression at all, it is a sort of encoding method
intended to get more usable dynamic range with fewer bits but it's still
straight PCM... just not linear PCM. I had no idea you could do it with
as few as 4 bits, but 8-bit u-law encoding is typical telephone quality
today.


Yes, and he never said "lossy compression". However there is plenty of
loss already inherent in those low bit encoding schemes anyway. The
whole point of MP3 etc was to *reduce* the audible loss at low data
rates. I'm sure you know this, but the old compression Vs compression Vs
compression linguistic problem raises it's head once again.