At 03:46 2007-05-23, you wrote:
>Raimund Specht wrote:
>
> >A typical
> >nature recording should always fit into the 96 dB dynamic range of the
> >16 bit format. If the conversion is made correctly, the noise floor of
> >the original recording will safely mask the (ugly) quantization noise
> >of the 16 bit format.
>
>Actually, it's the ugly noise of -truncation- that he's talking
>about. Truncation is simply chopping off the lower bits. That sounds
>ugly (and is one reason why people hated some of the earlier digital
>recordings).
So.. there was a possible sense in what those guys did, back
then, when they copied their digital tracks to their Ampex and back?
Covered some digital noise with tape hiss and modulation noise? Is
that possible?
I mean, they were terribly ridiculed, still perhaps right, but in a
way that we didn't understand at the time?
Klas.
>There was a discussion of dither on the pro audio list, and I asked
>about "self-dithering" signals, where it seems like the the noise
>floor of the recording ought to make truncation no problem without
>dither.
>
>The response, from those who know much more than I, was that no, it
>won't work optimally. Correctly forumulated dither doesn't mask
>quantization noise, it prevents it. I saw charts showing that it took
>a very high level of pink noise to mask the artifacts that a much
>lower dither noise would have prevented.
>
>Unfortunately, I wasn't able to get a layman-understandable
>explanation out of the real engineers and mathematicians (I just play
>one at work). But what I did get was a rule:
>
>Always dither any reduction in bit depth. Better safe than grainy!
>
>-Dan Dugan
>
>
>"While a picture is worth a thousand words, a
>sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause
>
>Yahoo! Groups Links
>
>
>
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