Need some brutefir help!!!

[Boscoe]

Hi All,

I'm having some trouble getting my brutefir setup working.

I'm planning on using the optical input and 8 analogue output channels of my X-Fi Titanium sound card for an active filtering system.

The thing is I have no idea how to map the inputs/outputs of the sound card to brutefir. The sound card is detected by the system and works. I can use speaker-test to generate audio output on the first two channels, the rest do not work.

Below is the output of aplay -l

I don't have any setup in my /etc/asound file, I have no idea how to do this. I haven't been able to find any documentation for it.

I have an analogue input and output on the sound card. I'm inputting 2kHz and getting nothing out. My current filter setup is a 1kHz high pass filter.

Any pointers or help would be much appreciated!

This is the output from brutefir when I start it.

BruteFIR v1.0m (November 2013)                                (c) Anders Torger

Internal resolution is 32 bit floating point.
SSE capability detected -- optimisation enabled.
Creating 4 FFTW plans of size 131072...finished.
Loading coefficient set...finished.
Realtime priorities are min = 2, usermax = 1, mid = 3 and max = 4.
Estimated CPU clock rate is 1097.511 MHz. CPU count is 2.
Filters in process 0: 0
Filters in process 1: 1
Warning: not allowed to set realtime priority. Will run with default priority
  instead, which is less reliable (underflow may occur).
Fixed I/O-delay is 131072 samples
Audio processing starts now

These are the input outputs I have setup in .brutefir_config.

## INPUT, OUTPUT ##

input "l_in", "r_in" {
        device: "alsa" { device: "hw:0"; ignore_xrun:true;};
        sample: "S16_LE";
        channels: 2/0,1;
};

output "l_out", "r_out" {
        device: "alsa" { device: "hw:0"; ignore_xrun:true;};
        sample: "S16_LE";
        channels: 2/0,1;
};

**** List of PLAYBACK Hardware Devices ****
card 0: XFi [Creative X-Fi], device 0: ctxfi [Front/WaveIn]
  Subdevices: 256/256
  Subdevice #0: subdevice #0
  ...continues to...
  Subdevice #255: subdevice #255
card 0: XFi [Creative X-Fi], device 1: ctxfi [Surround]
  Subdevices: 256/256
  Subdevice #0: subdevice #0
  ...continues to...
  Subdevice #255: subdevice #255
card 0: XFi [Creative X-Fi], device 2: ctxfi [Center/LFE]
  Subdevices: 256/256
  Subdevice #0: subdevice #0
  ...continues to...
  Subdevice #255: subdevice #255
card 0: XFi [Creative X-Fi], device 3: ctxfi [Side]
  Subdevices: 256/256
  Subdevice #0: subdevice #0
  ...continues to...
  Subdevice #255: subdevice #255
card 0: XFi [Creative X-Fi], device 4: ctxfi [IEC958 Non-audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: PCH [HDA Intel PCH], device 0: ALC887-VD Analog [ALC887-VD Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

 

[HenrikEnquist]

If you take a step back, can you get a simple loop working with alsaloop?
Ubuntu Manpage:

alsaloop - command-line PCM loopback


I don't see anything obviously wrong in your brutefir config. You could try specifying device in addition to the card (for both input and output), so go from "hw:0" to "hw:0,0" (for device 0 on card 0).



It looks as if the X-fi card presents its 8 channels as 4 stereo devices instead of a single 8-channel device. This makes it more complicated to use, but should still work. I haven't tried it myself, but BruteFIR supports outputting to several devices, and in this case they all share the clock so there won't be any drift problems between channels.
There is also the possibility to join the 4 devices to one with an alsa multi device. I don't know if there is any advantage compared to letting BruteFIR do it, but it's an alternative:
Alsa Opensrc Org - Independent ALSA and linux audio support site

 

[Boscoe]

If you take a step back, can you get a simple loop working with alsaloop?
Ubuntu Manpage:

alsaloop - command-line PCM loopback


I don't see anything obviously wrong in your brutefir config. You could try specifying device in addition to the card (for both input and output), so go from "hw:0" to "hw:0,0" (for device 0 on card 0).



It looks as if the X-fi card presents its 8 channels as 4 stereo devices instead of a single 8-channel device. This makes it more complicated to use, but should still work. I haven't tried it myself, but BruteFIR supports outputting to several devices, and in this case they all share the clock so there won't be any drift problems between channels.
There is also the possibility to join the 4 devices to one with an alsa multi device. I don't know if there is any advantage compared to letting BruteFIR do it, but it's an alternative:
Alsa Opensrc Org - Independent ALSA and linux audio support site

Thank you for your reply. I have managed to get the system working by enabling capture on the 'Line Input' on my sound card which is the input I am using in alsamixer.

The problem is I now have loop through from the 'Line In' to my front left and right outputs. This means I get some very strange combinations at the output of this channel - the rest are fine. So now I'm looking at how to disable this loop back as I'd like to have 8 channels output. There's advice saying this is possible in alsamixer but I don't have the option for it...

 

[phofman]

Perhaps the "Line Playback Volume"?

 

[Boscoe]

Perhaps the "Line Playback Volume"?

That's correct! Thank you.