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crazygringo·

What did he mean by CD distortion?

I'm also not super clear on how digital video would have jitter in a way that analog video wouldn't?

I totally agree with his overall sentiment, I'm just a bit confused on the specific examples.

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Good questions. CD distortion include hard clipping from amplifying too much, whereas vacuum tubes and magnetic tape have soft saturation (still a distortion, just a different kind). Another distortion is that dynamic range compression is used, bringing up the volume of quiet parts of a song.

As for digital video jitter, I can think of MPEG compression artifacts, both spatial (e.g. DCT mosquito noise) and temporal (e.g. motion compensation errors, periodic keyframe refreshes).

That is bad mastering, not an inherent property of CDs.

It's not, but it's very, very common, basically the rule in fact, starting I think in the early 2000s.

I read that, at least early on, many CDs were mastered with inadequate dithering, resulting in audible quantization noise.

There is something in CD that is noticeable by listening to vinyl, CD, and optionally mp3. I'd say CD makes everything sound like a harpsichord, but just ever so slightly. Maybe it's encoding or maybe it's decoding. Or something else. It's a first generation digital format, after all.

Analog videos never stutter but digital formats tend to have non-constant processing cost and do stutter occasionally. Maybe he's referring to that?

> I'd say CD makes everything sound like a harpsichord

Ha, that's a great description. Yes -- you're hearing more high frequencies.

Which is by design, because they're there in real life. Vinyl cuts off the highest frequencies, as do MP3's.

Nothing to do with first generation though -- if you listen to a FLAC on your computer with wired headphones the highest frequencies are still there.

It's a feature not a bug. :)

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