From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: What are subdevices?
Date: Mon, 27 Oct 2014 20:46:45 +0100
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dE wrote:
> typically cards have a single analog device but support multichannel
> output. So how does this work at the software level? If ALSA can't
> send multiple streams of audio to one device, then how does ALSA send
> separate output to different channels of the device?

The channels are not separate.  For a stereo devices, the samples are
arranged like LRLRLRLRLR...; for more channels, there are more
interleaved values: 123456123456123456123456...


Regards,
Clemens