On 10 May 2003 at 13:03, Jinx wrote:

> I've made a start on testing the sound system. Here are
> some traces of various frequencies and what happens
> to them after sampling
>
> http://home.clear.net.nz/pages/joecolquitt/gw_samples.html
>
> It appears that modulation gets increasingly worse

Aha! This tells all. Notice the 22.5KHz @ 44.1Ksps wave? There is
one! There shouldn't be anything, because the lowpass filter on your
sound card should have cut off before 22.05KHz.

So either your sound card is crappy, or the driver isn't turning on the
filter.

Get another sound card or build yourself a lowpass filter for the input to
this one.

Cheerful regards,

Bob

P.S. You might give Cool Edit a try if you are looking for a good sound
program for the PC. It won't fix your sound card, but it's a good
program.

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