D1info

24/96 Output in Ubuntu 10.04 to the Maverick D1


Forewarning: This is not meant for the linux illiterate, i've tried to make this guide as newbie friendly as possible, but some knowledge of the command line is expected.


Step one is to disable Pulseaudio from autospawning on login, we won't uninstall it, but it won't start up on login anymore, leaving you just ALSA.

To do this, run "sudo nano /etc/pulse/client.conf" in terminal and uncomment the line "; autospawn = yes" and change yes to no, leaving you with: " autospawn = no" then save that and exit.

Next, make sure "libasound2-plugins" in installed via synaptic package manager.

Then, you open your favorite editor again, gedit or nano for instance, and create a file named ".asoundrc" (minus quotations) and inside paste this code:

pcm.!default {
        type hw
	card 1
	device 0

}
pcm.rate_convert {
    type plug
    slave {
        pcm "hw:1,0"
        rate 96000
    }

}

defaults.pcm.rate_converter "samplerate_best"




Save this file in your home folder. Now I recommend restarting, and if all went well, pulseaudio should no longer be running and you will have full 24/96 output with the highest quality upsampling algorithm for non-24/96 files so everything is output in 24/96. The only drawback is that it puts a decent load on your CPU, i've got a bottom of the line C2D and with 24/96 files it uses a solid 10%, and with non-24/96 files approx. 15-20%. Also, make sure your alsamixer levels are set appropriately after you restart, I usually keep mine around 40% for both master and PCM. To set them, run "alsamixer" in your terminal of choice. Lastly, since were using alsa, there can only be 1 output at a time, so you have to close out your music player if you want to watch a youtube video for instance as there can only be one open stream at a time. Its a pain, but its a necessary sacrifice for audio quality, especially if you use your machine's audio mainly for music library playback like I do.


Troubleshooting: If you get no sound on startup, make sure that your using the right PCM device. In this case, i've got my internal audio card, and my D1 through USB. Its the second sound card (1) and the first device number (0) so, "hw:1,0" in this case. To make sure that your Maverick wasn't assigned a different hw number, open a terminal and run "aplay -L" and you should see a listing for USB Audio, and the device number, you can simply replace that number with the ones in my above posted .asoundrc to get what you need. Also check your alsamixer levels to make sure nothing got muted.