Version 1 (modified by adi, 15 years ago)
short explanation how to use jackd/ffado for alsa-only applications.

Running ALSA applications with FFADO

Once you have your jackd running with FFADO, you would probably also like to use some non-jackd applications, i.e. sound from the flash plugin in your browser. While it's usually possible to configure programs like mplayer, qmmp or gstreamer to use jackd directly, you cannot do so with others (once again: flash).

According to http://alsa.opensrc.org/index.php/Jack_(plugin), there's a way to reroute the ALSA output to jackd. On Debian-based systems, you'd need to install libasound2-plugins, other distros may vary:

# apt-get install libasound2-plugins

Afterwards, change your ~/.asoundrc:

pcm.!default {
    type plug
    slave { pcm "jack" }
}

pcm.jack {
    type jack
    playback_ports {
        0 system:playback_1
        1 system:playback_2
    }

    capture_ports {
        0 alsa_pcm:capture_1
        1 alsa_pcm:capture_2
    }
}

ctl.mixer0 {
    type hw
    card 0
}

Note that you don't have to provide target names for the playback ports. If you prefer to start your alsa application without connecting to system:playback_1, just omit them, but keep the channel numbers (0,1):

pcm.jack {
    type jack
    playback_ports {
        0
        1
    }
[..]

If you need to automatically connect one channel to more than one jackd destination port, then take an approach as outlined in http://www.alsa-project.org/main/index.php/Asoundrc#Virtual_multi_channel_devices. Of course, you could still create multiple connections of the same output by hand (e.g. in qjackctl)