<tt>Yes, it makes sense. Though, you must be sure nothing enters into your
electroacoustic chain. Other than real sounds, you also have also to
consider any electric interference coming from the environment in
which you're working.</tt><br>
<br>
<tt>Just as an example, while working on an oceanographic ship I needed to
sample wideband hydrophones at 1 MHz to avoid aliasing due to heavy
interference in the range 200 to 400 kHz. Then I filtered out unwanted
frequencies by using software filters, and the final step was
downsampling.</tt><br>
<br>
<tt>Depending on the equipment you have and the context in which you're
working, oversampling can be a solution to avoid the use of expensive analog
filters (sharp filters at very high frequency are normally expensive!). An
additional positive effect of oversampling is a reduction of quantization
noise when using industrial boards with 12 or 14 bits of resolution.</tt><br>
<br>
<pre style="margin: 0em;">Gianni
[EMAIL PROTECTED]</pre><br>
<pre style="margin:
0em;">--------------------------------------------------------------
Gianni Pavan
Email [EMAIL PROTECTED]
Centro Interdisciplinare di Bioacustica e Ricerche Ambientali
Universita' degli Studi di Pavia
Via Taramelli 24, 27100 PAVIA, ITALIA
Tel +39-0382-507874
Fax +39-02-700-32921
Web <a href="http://www.unipv.it/cibra";
rel="nofollow">http://www.unipv.it/cibra</a></pre><br>
<tt><br>At 17.26 10/05/2004, you wrote:
</tt><blockquote style="border-left: #0000FF solid 0.1em; margin: 0em;
padding-left: 1.0em"><pre style="margin: 0em;">Does anyone can point out
problems or disadvantages of
using the frequency response of transducers and/or
amplifiers (e.g. due to GBP limitations) to avoid
aliasing?</pre><br>
<pre style="margin: 0em;">If for instance I use a transducer with a response
that drops past 100 kHz and an amplifier with a
similar frequency response, and I sample my signal at
500 kHz, I could avoid aliasing without having to use
a low pass filter before the analog-to-digital stage.
Does this makes sense?</pre><br>
<tt>All the best,</tt><br>
<br>
<tt>Ricardo Antunes
</tt></blockquote><br>
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