PulseAudio performance test (Karmic?)

[onemyndseye]

This is getting alittle off topic but It took some work to figure out so I thought I would include it. This is how I set my laptop up for gaming and movies in surround.

This laptop has 5 speakers total: Shown here

They represent the following channels:
1 - Front Left
2 - Front Right
3 - Rear Left
4 - Rear Right
5 - LFE/Subwolfer (Bottom of laptop)
The OpenAL config: ~/.alsoftrc

format = AL_FORMAT_51CHN16

refresh = 6144
#sources = 256
stereodup = True
drivers = alsa

##
## ALSA backend stuff
##
[alsa]

device = lenovo_surround  # Call my virtually maped device
#periods = 0
mmap = true

Then I needed a proper speaker map to get "5.1 surround".

The default surround device (pcm surround51) had my channels alittle mixed up so I remaped as follows. The syntax I learned for this maping is ` ttable.MAP_CHAN.REAL_CHAN GAIN '

MAP_CHAN = Represented channel
REAL_CHAN = Actual channel as identified by alsa
GAIN = Gain/Volume at a fraction (1 = 100%)
~/.asoundrc

pcm.!default {
	type plug
	slave.pcm "lenovo_surround"
	slave.channels 6
	route_policy duplicate
}


pcm.lenovo_surround {
        type route
        slave.pcm surround51
        slave.channels 6

        # Front  with 50% volume LFE for both channels
        ttable.0.2 0.7	## Front Left		(Speaker 1)
        ttable.1.3 0.7	## Front Right		(Speaker 2)
        ttable.0.5 0.5	## Touch sub		(Speaker 5)
        ttable.1.5 0.5	## Touch sub		(Speaker 5)

        # Rear with 50% volume LFE for both channels
        ttable.2.0 1.0	## Rear Left		(Speaker 3)
        ttable.3.1 1.0	## Rear Right		(Speaker 4)
        ttable.2.5 0.5	## Touch Sub		(Speaker 5)    
        ttable.3.5 0.5	## Touch Sub 		(Speaker 5)   

        # Center (Spkr1+Spkr2) with 50% volume LFE  
        ttable.4.2 0.5	## Center Left		(Speaker 1)
        ttable.4.3 0.5	## Center Right		(Speaker 2)
        ttable.4.5 0.5	## Touch Sub		(Speaker 5)  
              
        # Center Rear  (Spkr3+Spkr4) with 50% volume LFE
        ttable.5.0 0.5	## Center Rear Left	(Speaker 3)
	ttable.5.1 0.5	## Center Rear Right	(Speaker 4)
	ttable.5.5 0.5	## Touch Sub		(Speaker 5)
}

Still playing with the volume levels abit to get that "just right mix" but I've tested this with RO and Quake4 with satisfying results. I dont expect this exact example to work for anyone else or do I truely believe it to be a 100% correct (for instance: the gains in most channels are too high. i.e. Center Rear should total to 1) example of mixing 5.1 surround, but it gave me the results I was looking for and hopefully will save someone the trouble of figuring this crap out lol.