output to two sound devices (card)

[bschwand]

Hello,

I have been reading up about sound support in FreeBSD (the wiki and also a lot about virtual_oss and jack) and saw this comment

Also virtual_oss can combine two different playback/recording devices into a single /dev/dsp device.

made by hselasky here https://forums.FreeBSD.org/threads/...tooth-headphones-on-freebsd.82671/post-606316

Does this mean it is possible to create a virtual oss device which sends sound to two actual audio cards ?
The use case I am seeking is this:
I have several monitors with integrated speakers, connected through hdmi.
I'd like a virtual sound output device which sends the left channel to monitor 1, and right channel to monitor 2 (or something more complicated)

Also, I do not understand well the mappings described in the virtual_oss man page for -M and -m options, is there more documentation and examples available somewhere ? The examples in the man page are nice but they do not describe exactly what is accomplished, so it's hard to correlate options and desired result.
For example,
- what is remote and local feedback ?
- use case for the 3 types of monitoring filters ?
- mix input and output channels, what are those ?

Thanks for any clarification, or pointers to some how level description and examples how those are used.

 

[cracauer@]

I would use jackd and qjackctl for this. You can then run pulseaudio on top of jack.

 

[shkhln]

Does this mean it is possible to create a virtual oss device which sends sound to two actual audio cards ?

That means virtual_oss can redirect recording to one device and playback to another.