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Date: Thu, 26 Jan 2006 04:50:43 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [PATCH] PC speaker emulation (square wave)
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To: qemu-devel@nongnu.org

Joachim Henke wrote:
> Ok, I simplified my patch to generate just plain square waves.  
> Indeed, its sound is much closer to a real PC speaker now.
> 
> Does "cut off frequency" mean, that we have silence above that  
> specific frequency? I changed my patch to go this way. Before, it  
> always played the highest possible frequency for that case (f > 16 kHz).

No, it means the higher-frequency harmonic components of the square
wave are attenuated, which affects how it sounds.  Filtering a square
wave in this way is particularly simple, but unlikely to be worth the
effort.

-- Jamie