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Old 22nd July, 2013, 09:30 PM
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Gizmo Gizmo is offline
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It's a generally accepted rule of thumb that converting from one audio format to another introduces a minimum of about 6 dB of signal loss (basically, you cut the fidelity in half). Once lost, that signal can NEVER be regained, although it MAY be possible to 'guess' at what was there (this is referred to as 'interpolation').

CDs are normally recorded as straight 16-bit PCM (wav, though WAV actually can encompass much more than just PCM).

When you ripped to OGG, that introduced 6 dB of distortion. As Aidan says, the OGG format made a guess as to what you could afford to do without, and I find OGG to generally be a pretty good format.

When you ripped from OGG to MP3 and MP4, each of those conversions intorduced additional distortion. But here's the thing: to go from any compressed format to any other compressed format, you have to FIRST convert to straight PCM (well, strictly speaking you don't HAVE to, but that's usually the simplest way). That step created distortion, which then had to be compensated for by the following compression algorithm. This produced 'artifacts' which are likely the reason the resulting file became larger. I would expect that if you ripped the original CD to MP3 or MP4, you would find that it produced a file of comparable size to OGG.
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