Linux.com

jborden

jborden

  • Linux.com Member
  • Posts: 4
  • Member Since: 20 Jun 09
  • Last Logged In: 08 Jul 09

Latest Posts

Posted by
Topic
Post Preview
Posted
  • jborden
    RE: UA-4FX advanced mode noise
    In answer my own question: according to some recent wiki posts, others with this device are having a similar issue. It seems that more reverse engineering is required to fix the problem.
    Link to this post 25 Jun 09

    In answer my own question: according to some recent wiki posts, others with this device are having a similar issue. It seems that more reverse engineering is required to fix the problem.

  • jborden
    RE: UA-4FX advanced mode noise
    [quote]It's possible that the noise is hardware related, perhaps due to external interference? The wiring is especially conducive to inducted spikes in the signal. Make sure that all cables and wires are kept a reasonable distance from power cables, wireless devices, and network cables.[/quote] In this case I don't believe that to be the issue. My reasons are that first, no noise in standard mode and second, no noise in advanced mode in that other OS.
    Link to this post 25 Jun 09

    It's possible that the noise is hardware related, perhaps due to external interference? The wiring is especially conducive to inducted spikes in the signal. Make sure that all cables and wires are kept a reasonable distance from power cables, wireless devices, and network cables.

    In this case I don't believe that to be the issue. My reasons are that first, no noise in standard mode and second, no noise in advanced mode in that other OS.

  • jborden
    RE: UA-4FX advanced mode noise
    [quote]I assume you've already run alsamixer and futzed with the volume levels there? I've seen some background noise get introduced when my Line-In and Mic levels were too high...[/quote] On this particular device there isn't a software mixing control. All volume control is done using mixing knobs on the device itself, but yes, adjusting those controls does not make a difference on the noise produced during playback. The volume knobs merely make all audio louder or softer, including the noise.
    Link to this post 24 Jun 09

    I assume you've already run alsamixer and futzed with the volume levels there? I've seen some background noise get introduced when my Line-In and Mic levels were too high...

    On this particular device there isn't a software mixing control. All volume control is done using mixing knobs on the device itself, but yes, adjusting those controls does not make a difference on the noise produced during playback. The volume knobs merely make all audio louder or softer, including the noise.

  • jborden
    UA-4FX advanced mode noise
    I've recently purchased an Edirol UA-4FX usb sound mixer, which is supported in a "standard" usb sound device mode which supports 16bit at 44.1Khz., and an "advanced" mode which allows up to 24bit at 96Khz as well as enabling use of the onboard midi ports. Alsa supports both the standard and advanced modes on this device, however, when I am in advanced mode, I am getting some extra background noise which is especially noticable at lower volumes and certain frequencies. I have attached a tar file containing two mp3s comparing the output of the standard and advanced modes. I've tried linux kernels 2.6.28, 2.6.29, and the git sources alsa code all with the same results. Is anyone else with this device having a similar issue? Note: the file was too big to attach, so here's some urls for each: Standard: http://209.90.109.2/test-standard-mode.wav.mp3 Advanced: http://209.90.109.2/test-advanced-mode.wav.mp3
    Link to this post 20 Jun 09

    I've recently purchased an Edirol UA-4FX usb sound mixer, which is supported in a "standard" usb sound device mode which supports 16bit at 44.1Khz., and an "advanced" mode which allows up to 24bit at 96Khz as well as enabling use of the onboard midi ports. Alsa supports both the standard and advanced modes on this device, however, when I am in advanced mode, I am getting some extra background noise which is especially noticable at lower volumes and certain frequencies. I have attached a tar file containing two mp3s comparing the output of the standard and advanced modes. I've tried linux kernels 2.6.28, 2.6.29, and the git sources alsa code all with the same results. Is anyone else with this device having a similar issue?

    Note: the file was too big to attach, so here's some urls for each:

    Standard:
    http://209.90.109.2/test-standard-mode.wav.mp3

    Advanced:
    http://209.90.109.2/test-advanced-mode.wav.mp3

Who we are ?

The Linux Foundation is a non-profit consortium dedicated to the growth of Linux.

More About the foundation...

Frequent Questions

Join / Linux Training / Board