From alsa-devel-owner@alsa.jcu.cz  Fri Nov 27 13:52:25 1998
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Date: Fri, 27 Nov 1998 13:47:57 +0100
From: Thomas Sailer <sailer@ife.ee.ethz.ch>
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Subject: Re: Linux sound cards latency
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Two things to keep in mind about latency:

If there is IDE activity and you haven't
set hdparm -u 1 /dev/hd*, you loose.
(Int latency will be horrendously high).

Also, some cards have a very long audio path
delay in hardware (usually depending on the
sampling rate), so the time a signal
arrives at its connectors may well be several
ms longer. This is an OS invariant.

Some cards, such as ESS, also have rather deep
FIFO's (128 samples or so).

Tom

