On Thu, Dec 16, 1999 at 08:06:26PM +0100, Gabriel Bouvigne ([EMAIL PROTECTED]) wrote
> ...
> It's right that it's not a lot, but I think it's important. As an
> example, a standard 10 or 15Hz high pass filter would be nice, as no
> one is able to ear such frequencies, so why encoding them?
A 10kHz filter, IMHO, would be a bad idea. Even in poor listening
conditions with less than adequate equipment this is noticable. It
will make most music have a more muddy and boomy sound.
15kHz would be OK for all but very demanding situations.
I'd guess that an 18kHz low pass filter would only be noticable with
very good/excellent conditions, and an experienced ear.
All of these estimates assume a good filter. Setting the coefs. to
zero in those regions probably isn't the best way. As mentioned in
previous emails, that could lead to some strange distortion.
If you use a soundcard/headphone combination for music tests, I'd
recommend getting good head phones, and checking out this web page for
the performance (especaially DtoA) of various sound cards:
http://www.pcavtech.com/soundcards/summary/. A sound card can make a
world of difference with its own performance characteristics at
various frequencies.
An audiophile,
John
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