On 19/05/2010, at 1:20 AM, Scott Fraser wrote:
> While the truth is that higher sampling rates unequivocally result in =
> greater bandwidth,
I feel greater bandwidth is is not the primary reason for going to higher s=
ampling rates. Doubling the sample rate - and this should be obvious from =
the term - doubles the number of times per second the original analog sign=
al is sampled, giving a more accurate representation of the information in =
that waveform. There is an article on the WSRS website written by Nagra's =
John Owen that makes a similar point:
"The sampling frequency and frequency response go hand-in-hand really, and =
although using the Nyquist theory, 44.1 kHz is sufficient to record perfect=
ly up to 22.05 kHz bandwidth, using higher sampling frequencies does appear=
to reconstitute the original sound more accurately."
see http://www.wildlife-sound.org/equipment/addup.html
I agree with Scott that the potential gains from 48khz don't compensate for=
the hassle.
The benefit of recording at 24bit is largely dependant on the capabilities =
of the A/D used in the recorder. Many of the so-called 24bit recorders, esp=
ecially if the design is a few years old, have A/D signal to noise ratios o=
f less than 96dB, so there is very little to be gained recording at 24bit. =
The FR2-LE uses an A/D chip with S/N of 95dB for example which effectively=
makes it a 15-6 bit recorder. Raimund's recorder tests are performed at 44=
.1khz/16bits (with one or two exceptions) which obscures the performance ad=
vantages of those recorders which are capable of more than 16bit performanc=
e. The Olympus is a case in point, with substantial improvements to perfor=
mance when tested at 24bit.
cheers
Paul
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