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4. Re: High Sample Rates

Subject: 4. Re: High Sample Rates
From: "Marinos Koutsomichalis" marinoskouts=
omichalis
Date: Thu Aug 20, 2009 7:02 am ((PDT))

I insist on what I already told in previous messages that seems to be
some how overlooked..=0D
I' ll try to explain it further though I am not an expert and I am  =0D
not sure whether what I say is absolutely correct,=0D
but as far as I am concerned that is the case.=0D

what the sample rate actually means is how many times per second the  =0D
actual analog signal will be sampled=0D
That is to say that when recording @ 44,1, the machine will measure  =0D
44100 times per second the amplitude of the signal and=0D
it will store these values somewhere. During playback these values  =0D
will be converted back to an analogue that WILL NOT be the same due  =0D
to the fact that only if we take infinite measurements we can have a  =0D
true digital representation of the signal. That is because has  =0D
absolutely no clue of what happens between those 44100 samples. So it
assumes that it should connect with a straight line every two  =0D
consecutive samples. This is hardly ever the case so we always have  =0D
slight deviations from the actual signal. That is referred to as  =0D
quantization noise.=0D

you can find some images here http://en.wikipedia.org/wiki/ =0D
Quantization_error=0D

So when you record on higher sample rates you take more measurements  =0D
per second, thus the precision is better and this means you get less  =0D
unwanted quantization errors.=0D



On 20 =CE=91=CF=85=CE=B3 2009, at 4:01 =CE=9C=CE=9C, dan.cesonrocks wrote:=
=0D

> Hello all,=0D
>=0D
> I just wanted to report some crossover information (about the use  =0D
> higher sampling rates) from the worlds of audiophiles and pro audio
> recordists.=0D
>=0D
> I won't pretend to be able to explain all the details, but will say
> that each of these groups seem to think that the justification for  =0D
> use of higher sampling rates in recording has next to nothing to do
> with whether we can hear (explicitly or subconsciously) or record  =0D
> frequencies above 22.05 kHz (the Nyquist frequency). Rather they  =0D
> seem to believe that use of higher sampling rates (in recording)  =0D
> results in better sound reproduction due to other factors, not the  =0D
> least of which are the filters employed to reduce digital artifacts
> (and which introduce their own issues).=0D
>=0D
> Apologies if this is straying from 'nature recording'.=0D
>=0D
> clay=0D
>=0D
> =0D










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