Equalization

[Macdelf]

I don’t know if anyone else is trying to get camilla to wok, but I have hit a snag. After replacing the device alsaequal with camilladsp I get “device not found”. Any advice is welcome.

The alsa_cdsp module is in the wrong location (my bad), you can correct it by running the following command:

Code:

sudo install -m 644 `pkg-config --variable=libdir alsa`/libasound_module_pcm_cdsp.so `pkg-config --variable=libdir alsa`/alsa-lib/

That got it to work. Thank You. One question I am using a Biquad High pass filter with a Q of 2. Camilla outputs coefficients (printed when run from ssh) that look like a Q of 0.5 instead. It is easier to ask than to try to measure it. I want the 6 dB peak in the frequency response. The speakers were designed to have it.


devices:
  samplerate: 44100
  chunksize: 1024
  queuelimit: 1
  capture:
    type: File
    channels: 2
    filename: "/dev/stdin"
    format: S16LE
    extra_samples: 8192
  playback:
    type: Alsa
    channels: 2
    device: "hw:0,0"
    format: S32LE

filters:
  hp_802:
    type: Biquad
    parameters:
      type: Highpass
      freq: 26
      q: 2.0

pipeline:
  - type: Filter
    channel: 0
    names:
      - hp_802
  - type: Filter
    channel: 1
    names:
      - hp_802

This seems to actually be correct. The coefficients reported by the command (using debug option) do not. The final result with Q=2 is about 6 dB higher near resonance as it should be. I tested with a scope and ohm meter. I have also increased the capture rate from above and all is good. Other B&W matrix owners should be thrilled as I am. No need for external “Bass Alignment Filter” when listening to digital. I had a lot of trouble putting a small box between my Krell preamp and amp as it added noise. Vinyl has very little content down around 26 Hz, but digital can from time to time.

Camilla is what I have been waiting for and may be the best thing about Moode 7.0
Tom