28 Jul
2003
28 Jul
'03
12:06 p.m.
Hello Anders,
At 14.00 28/07/2003 +0200, you wrote:
It becomes even more interesting when you bring in
dither. Then you can
represent signals whose amplitude is less than one bit, and you can
increase time resolution to infinity.
...
well I agree with anything else you have written but here there's a basic
relation that sets a limit on time resolution of a linear system:
df * dt > 1/2
Here d is "delta" and not "differential", f is frequency and t is
time.
This relation applies to any signal and/or any linear system. So the
limited bandwith of a PCM system sets a lower limit on time resolution. For
sure dithering allow for the almost complete use of the available time
resolution, and also increasing the semple rate increase time resolution,
but as usual the big question is: does it matters to our ear? I think no,
and with this respect I completely agree with you.
Bye,
P.S. I have yet to test the latest BF with fftw3. My RedHat 7.3 has a
bugged gcc which fails to compile the sse support for fftw3, losing much of
the advantages of fftw3. I filed a bug report and I'm waiting for an answer
from RedHat.
--
Denis Sbragion
InfoTecna
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