What is the point of expensive CD players?
On Mon, 13 Nov 2017 08:31:00 +0000, Brian Gaff wrote:
Jitter now the thing about this is that in pre jitter days, digital
audio sounded decidedly odd.
The absolute levels were erroneous quite often.
The blurring with jitter has actually made CDs sound better but of
course
if you had infinite bits then you would not need it would you.
I think in a way this is all a bit of a pink herring, as I don't think
anything like a perfect recording and playback system has yet been
designed as the world is not perfect. Our ears are designed so that
intermodulation of a natural kind is considered pleasant, after all you
would design ears linear if you wanted distortion free sound.
It reads like you're confusing jitter for *dither*, Brian. Jitter is
small unwanted time displacements of each successive sample whereas
*dither* is an artificial noise component added to mask the unpleasant
sound of quantization noise that afflicts signals that are very close to
the silence point which would correspond to samples that encompass values
equating to less than the lowest digital value that the system can encode.
Without the addition of a dither noise signal, a recording of a piano
note fading into silence would degrade into something not unlike
crossover distortion in class B push pull amplifiers or the effect of a
loudspeaker with a rubbing voice coil (or an analogue tape recording made
without any recording bias, both DC or ultrasonic ac bias). Dithering
noise added to the signal replaces the extremely unpleasant quantization
noise with something far less objectionable, vastly improving the quality
of the audio during the very quiet passages that approach the quietest
end of the dynamic range limit of the recording system.
--
Johnny B Good
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