Subject: Re: [ecasound] Question about multichannel sound cards
From: Kai Vehmanen (k_AT_eca.cx)
Date: Thu May 22 2003 - 00:44:54 EEST
On Sat, 17 May 2003, Luis Pablo Gasparotto wrote:
> What should I do to play different wave files to different soundcard channels?
-a:1 -i foo1.wav \
-a:2 -i foo2.wav -erc:1,2 -eac:0,1 \
-a:3 -i foo3.wav -erc:1,3 -eac:0,1 \
-a:4 -i foo4.wav -erc:1,4 -eac:0,1 \
-a:1,2,3,4 -f:16,4,44100 -o alsa,default
... opens the soundcard in 4ch mode and writes each of the files to
different channels. The -eac is needed to mute the first channel after
copying. Also, you probably need to add -ea:400 to each chain to normalize
the output volume level.
Btw; having to add the -ea:400 is one annoyance I'd really like
to get rid of, but unfortunately changing the way ecasound
downmixes multiple chains would break way too many existing
chainsetups. I've been thinking about adding a new mode
(-z:sumdownmix?) that would select a JACK style mode where
inputs are just summed together without division (introduces
risk of clipping, but is closer to how analog mixers work
and thus possible more intuitive for users).
-- http://www.eca.cx Audio software for Linux!
This archive was generated by hypermail 2b28 : Thu May 22 2003 - 00:46:12 EEST