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Old 2015-11-19, 12:21 AM
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paddington paddington is offline
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Join Date: Jan 2005
Location: UK
Re: MP3 or MiniDisc?

frequency roll off is a poor indicator of lossy data compression. It might be from a codec or it might be due to the source. It doesn't mean anything, by itself.

Plenty MP3 modes don't roll off, at all.

You must look for unnatural sounds. Those big holes and hard, deep steps are clear indications of lossy data compression. The audio is missing in places the codec believes you won't notice. And you generally don't... what you *do* notice is the aliasing from the edges of the missing chucks. That's the glassy / slushy sound you'll hear in lossy digital audio.

That doesn't look like a clear case of ATRAC (MD) compression to me, though it certinaly could be a later version of ATRAC which looked more like MP3. Or maybe it's just a higher-bitrate MP3.

Either way, it seems to have been through a lossy compression codec at least once.

the most glaring ATRAC compression and most common before 2008 or so looks like this:

"There are some of these recordings where it is just a whirring, and you cannot hear the music. " - Jimmy Page, 2007 / JUL / 26
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