glenbadd wrote:
On Oct 19, 1:11 am, Sebastian Kaliszewski
wrote:
Well, the software to perform such test is AFAIR available for free. One
needs 24/192 recording, reduce it down to 16/44.1, upsample back to
24/192[*] (the information lost will to be restored) and comprare
original with processed audio using some ABX software.
No need for some expensive vinyl equipment, etc... Just some good 24/192
recording, and as I understand you have such recordings handy.
*] - upsampling step requires explanation -- some audio equipment can't
promptly and hands free switch sample rates -- that way there will be no
such problem, playbacksettings will be the same, etc. It isolates pure
16/44.1 vs 24/192 difference
Upsampling and downsampling generally uses non-linear
algorithms, such as sinc and polyphase,
So what? Sampling (AD conversion) is non linear by itself. The whole
point is to keep non-linearities in the restored analog signal down to
some low dB. Proper ADC - DAC chain will hold those very close to
theoretical minimum possible.
And it is the same with resampling. Proper resampling (and virtually all
quality audio editting software does it the propoer way) keeps
nonlinearities where they should be (i.e. down at theoretical minimums).
? so your comparison
is almost guaranteed to be different.
Nope.
This is the very nature of difference between 16/44.1 and 24/192 (or any
two different sets of bit depth-sample rate. In fact this is the way
oversampling DACs work -- signal is upsampled and then DA converted and
then simpler restoration filters could be used.
Ref. http://leute.server.de/wilde/resample.html
I'm affraid You're confusing linear interpolation of sample points and
linear transformation (distortion, filter) in signal processing. Linear
interpolation of sample points is a non linear transformation of signal.
It's like confusing piano, an instrument, with piano -- quiet passage in
music -- one can play forte on a piano
rgds
\SK
--
"Never underestimate the power of human stupidity" -- L. Lang
--
http://www.tajga.org -- (some photos from my travels)