By default, Ubuntu Hardy Heron uses PulseAudio for audio mixing, which disables surround sound by default. I just bought new 5.1-channel speakers, but I was only heard sound coming from the front two. Disappointed, I went searching for the answer in the forums. If you want surround sound on your Linux setup, keep reading below..

Like I said above, Ubuntu now uses PulseAudio by default, so it dictates the kind of output you’ll be getting from your sound card. Luckily, PulseAudio makes it very easy to enable surround via a simple configuration file. I followed instructions here for editing via the command-line, but using a GUI should be just as easy.

• Press Alt-F2 to open a “Run” dialog, and type “gksudo nautilus“. This will give us a file-browser with administrator privileges.
  

  Warning: With this file browser we have access to do almost anything to our system. Follow these instructions carefully, or things could get bad!

• In the file browser, click on the “File System” icon on the right. Then navigate into the “etc” folder, and then “pulse”. This is the folder where our configuration file lives.
  
• Make a backup of “daemon.conf”. Do this by selecting the file, copy it, and then paste it in the same directory. Right click the new copy and rename it “daemon.conf.bak”. This is just in case things go wrong– it’ll be easy to revert back to the original settings.
  
• Now we’re going on edit the settings file. Double-click on “daemon.conf” to open it in a text editor. Remember that we have administrator privileges, so be very careful of the changes you make!
• Find the following line in the file, it should be towards the bottom:
  

  ; default-sample-channels = 2

  First, remove the “;” character to “uncomment” the line. Then change the value from 2 to either 6, for 5.1 surround sound, or 8 for 7.1 surround. For example:

  default-sample-channels = 6

  
• Save the file and exit the text editor and file browser. This is important so we don’t accidentally make more changes with administrator access.

That’s it for the hard part. For the changes to take effect, you will need to restart your computer. Afterwards, there is a simple command that you can use to test your surround sound. Press Alt-F2 to start the “Run” dialog, and enter the command:
speaker-test -Dplug:surround51 -c6 -l1 -twav
or to test 7.1 surround:
speaker-test -Dplug:surround71 -c8 -l1 -twav

This will play a sound from each speaker telling what channel it is set to. You should hear audio out of each one. If you don’t then you may have some of the channels disabled. Check them with the volume manager:

• Right click on the volume meter in the panel and press “Open Volume Control”.
  
• Make sure the “ALSA” mixer is selected. Go to File, Change Device, and select the one that contains “Alsa Mixer”.
• By default, many of the channels are hidden. Select Edit, Preferences. Make sure you have at least the following selected: Master, Front, Surround, Center, and LFE (and Side if using 7.1 sound)
  
• Now, make sure none of the channels are muted under the “Playback” tab. If they are, un-mute them.
  

  Then use the test command above to try again.

At this point you should have surround sound working via the test command. However, some applications may also need to be setup to use surround sound. Rhythmbox should play music using surround by default. However, Totem Movie Player needs to be configured for it. To do so:

• Open Totem Movie Player from the Applications menu under Sound and Video, Movie Player.
  
• Select Edit, Preferences, and click on the “Audio” tab
• Set the “Audio output type” to your surround-sound preference. For example. 5.1-channel.
  

Other applications or webpages that use Flash may not use surround sound correctly. You can test if an application is using surround sound using the PulseAudio volume meter. To do so, press Alt-F2 to open the “Run..” dialog, and enter the command “pavumeter“. You should see sound in each channel.

I’ve been very happy with my surround sound so far. What experiences have you had? Did these instructions work for you? Are there any other applications you’ve found that don’t work with surround sound? Post in the comments.

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So what made the movie so good? For a film based on a comic book, Iron Man took itself very seriously. There were no emo dance scenes a la Spiderman, anyway. Serious does not mean boring or dry though. Iron Man was funny; actually, it was hilarious at times. Robert Downey Jr. was the perfect match for this military mogul: smart, confident, and drunk. Speaking of smart, I don’t think there has been another comic hero movie where the main character’s super power was his smarts. At least not like Downey’s character, Tony Stark. Stark is an engineer capable of building amazing power sources the size of tennis balls out of scraps in a cave. He is an expert with computers, soldering, metalworking…pretty much everything needed to make the most powerful suit in the world. Convenient for him, huh?

I highly recommend this movie. It is action packed, but doesn’t focus on the explosions or fight scenes. As I mentioned earlier, it is also really smart and funny as well. I think those are the three elements that make for a great action flick. In the end Iron Man is about the struggle we as Americans go through having the most powerful military in the world. The best defense is a good offense, but what happens when our offense falls into the hands of our enemies?

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