Sudo Radio

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Revision as of 23:21, 27 May 2013 by Mk30 (talk | contribs) (link to old stuff)
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From the sudo studio we broadcast music and other live content to the Sudo Radio livestream which you can listen to at http://radio.sudoroom.org/ (click the big GREEN button that says Radio Room Stream).

What do we have in the sudo studio?

  • A computer that you can use to 1) record and produce audio or 2) play live content (music, talking, whatever) on our livestream.
  • A way for you to come in and plug in your computer or other music player to play content live on our livestream.

How can I have a show on the radio?

Email us, come to a meeting, tell us you want to do it and you can do it! We are looking for people who want to share interesting content on the radio!

What is your studio and livestream set up like?

The heart of our studio is a physical mixer that takes audio in from two sources and lets you switch between them (this is called “cross fading”). Imagine that it’s like a turntable but without the records. Instead of records, we have channel 1 and channel 2 which are empty spots that you can plug anything that produces sound into - a computer, a second computer, an electronic instrument, a mic, etc.

We currently have channel 1 set up to play any audio that the studio computer produces. Channel 2 connects to an unplugged minijack (also known as an “1/8th inch” or “the cord that lets you plug your headphones computer speakers into your computer or music player http://en.wikipedia.org/wiki/File:Audio-TRS-Mini-Plug.jpg) that allows anyone to play audio directly from their own computer or music player (anyone can just plug this cord directly into the spot on their computer or music player where headphones or computer speakers would go).

On the studio computer people can either play music from our huge internal collection or from the internet.

Our internal collection is located on a shared sudo room drive, or what we call the “audio server.” The songs on it have been added by lots of different sudoers, so it has all kinds of music on it! IIf you are currently at sudo room and connected to the sudo room wifi, you can browse (and play!) the music on our server: https://sudoroom.org/wiki/Music). We also very much encourage you to add music to the server. Instructions are here: https://sudoroom.org/wiki/File_server

To play music from our collection, we use an open source (http://www.brighthub.com/computing/linux/articles/62137.aspx ) DJ program called Mixxx. Mixxx is the equivalent of a turntable. It allows you to queue up a current track and a reserve track, cross-fade between the two tracks, do a number of sound effects, create a playlist, and speak on the air. Mixxx’s “library” of music is just all the music in our audio server.

To play music from the internet, people can just use firefox.

So now that we’ve covered what music sources we can play FROM, where does the audio go? The physical mixer is the thing that’s in the middle of everything. It takes audio IN and puts music OUT. The two IN sources are the computer and the unplugged minijack (which connects to your own computer/player). The OUT source goes through a number of places and eventually ends ON THE INTERNET! ….in a livestream located at http://radio.sudoroom.org/ (click the big GREEN button that says Radio Room Stream.) What is the process that takes it from the mixer to the internet?

The first stop is the digital audio interface. The digital audio interface (http://en.wikipedia.org/wiki/Digital_audio) converts analog sound (the physical mixer sends analog sound OUT) into digital sound (analog sound goes into the interface and digital sound comes out of the interface to fly into the internet). The interface is a tiny box that’s taped to the front of the wooden stand to the right of the computer in the studio. So where does the interface send the newly minted digital sound it produces?

It sends it to a tiny computer called a Raspberry Pi (aka Rpi) (http://en.wikipedia.org/wiki/Raspberry_Pi). The Pi sits on the top shelf of the wooden stand in the studio. The only thing that the Pi does is constantly send whatever it gets in on to the livestream, which means that it broadcasts whatever it receives onto the internet.

So now that you have a sense of how our physical layout is set up, you are probably wondering how the livestream works..how the Raspberry Pi does its magic...how to set this up yourself...and much more. These are all details that will be added soon (and you can always email us or drop by to learn more!)

I am ready to do a show. How do I use your studio to play live content?

We have two options: people can play audio directly from their own computer or music player OR they can use our studio computer to play music from our huge internal collection or from the internet. Keep reading for specific step-by-step instructions for using our studio to play live content.

When you are first coming in to the studio, make sure that everything is connected and working properly:

  • Ensure that the physical mixer in the studio is set to play music from the studio computer:
    • Make sure the mixer is on (red light above the power button should be on).
    • The crossfader at the bottom should be set all the way to the left toward CH 1.
    • Above that, the CH 1 volume should be about ⅔ of the way up.
      • CH 2 should be all the way down.
    • Above that, the switch between “Phono 1” and “Line 1” should be set to Line 1.
  • Restart the computer.
  • Once you’ve restarted, check the computer’s sound settings
    • Click the little volume icon next to the time in the upper right. At the bottom of that menu, choose “Sound Settings...”
    • In Sound Settings, under Output, ensure that “Analog Output” is selected.
    • Under Input, ensure that the selected option is “Microphone: Storm HP-USB500 5.1 Headset. Test to see whether it’s working by tapping or talking into the microphone and checking the “Input level” as you do that. If the microphone is working, you should see pale orange lines on the input level (they are very hard to see!).
  • Check http://nthmost.net:8000/rpi to ensure that the livestream is running. If you get an error (“The file you requested could not be found”), restart the raspberry pi which runs the livestream (this is a very small computer located on the top shelf of the wooden end table. You restart it by unplugging the wire on its right and plugging it back in. After you unplug and plug it back in, wait 30 seconds and refresh the livestream page. If it still gives you an error, alert someone!!!

Once you’ve made sure that everything is correctly hooked up and working properly, you can either play music from our huge music library using the Mixxx DJ software, or you can play music from the internet. We encourage you to use Mixxx as we have a huge selection of music that’s typically better sound quality than music from the internet.

Playing music from our huge music library with the DJ software Mixxx

  • Our DJ system is an open source ( http://www.brighthub.com/computing/linux/articles/62137.aspx ) program called Mixxx. Mixxx is the equivalent of a turntable. Mixxx allows you to queue up a current track and a reserve track, cross-fade between the two tracks, do a number of sound effects, create a playlist, and speak on the air. Mixxx has a lot of music available in its library. The music in its library comes from our audio server (where all of the shared music of sudo room lives). (We encourage you to add music to our audio server! Check out the instructions for adding music to the audio server: https://sudoroom.org/wiki/File_server)
    • Please note that Mixxx is for playing music off the server and off the computer located in the studio. If you’d like to play music from your own music player or computer, you don’t have to use Mixxx. If you’d like to play music off a website, follow the instructions below.
  • When you start Mixxx, it will take its sweet time to scan our server and import everything into its library.
  • As it’s doing that, you can add things from the library (the list of songs at the bottom of the screen) to the left slot and the right slot. To add tracks, right click on them and select “Load to Deck 1” (for the left) and “Load to Deck 2” for the right. Loading to the deck only queues the song up, but doesn’t play it. In order to play a song on either side, hit the play button for the side that you want to play (the play button is right by the CUE button). For more info (or if the above instructions are totally confusing), check out this basic tutorial for Mixxx: http://www.youtube.com/watch?v=g8ezCqolx04.
  • If you’d like to talk on the radio, click and hold the ` key for the entire time you’re talking.
    • If you can’t hear the mic:
      • First ensure that you’ve got the correct sound settings for the computer.
      • Second, check Mixxx’s audio settings. To do this, first mouse to the very top of the screen (to the right of where it says “Mixxx” in the very upper left of the screen). Click “Options.” Under options, go to “Preferences.” On the preferences page, on the Input tab,
      • Input: Microphone: Blue Icicle: USB Audio (hw:1,0) // Channel 1
        • All others should be “None.”
        • The “Microphone” setting should be “Blue Icicle: USB Audio (hw:1,0)” and “Channel 1.” If that setting is already there, the mic may still not work. Set the microphone setting to None, hit apply, set it to Blue Icicle again, hit Apply, and then hit OK. This should make the mic work.
        • NOTE: If Blue Icicle isn’t an option for the Microphone setting, make sure it’s plugged into the usb port in the back of the computer. If it is plugged in, unplug it and plug it back in. However, if you had checked the audio settings on the computer first, hopefully this shouldn’t happen!
  • Grats, you’re good to go! Knock yourself out! Play all the music on the server! Talk as much as you want! YAY!

Playing music from websites

Apparently some people like to play music from the internet. You may be one of the people who wants to use the computer in the studio to do this!

  • If you want to play music off the internet, make sure to open firefox first thing when you start the computer. Don’t open Mixxx first. If you’ve already opened Mixxx or if Mixxx was already open on the computer when you got to it, restart the computer. Just to reiterate, if you open Mixxx first and want to play music off the internet later, you will need to restart the computer :(
  • To talk on air, use the black microphone that’s connected to the physical mixer. To do this:
    • The mic on the physical mixer is plugged in on the upper left (where it says “MIC”).
    • Below that you should see a switch that says “ON.” This is the switch for the mic. Keep it in the “OFF” setting until you want to talk (otherwise it will pick up your typing and any other studio noise).
    • When you’re ready to talk, flip that switch to the right to “TALK OVER” and turn the CH 1 volume to 0 (or just quieter so that you can talk over the music).
    • When you’re done talking, turn CH 1 back up to somewhere between 5 and 8 and flip the mic switch back to “OFF”

How to play music from your own music player or computer

  • The studio should have an unplugged minijack with a piece of orange tape on it that says “LINE 2.” You can just plug this directly into your computer or music player. The other end of this cord is connected to the physical mixer.
  • Ensure that the physical mixer in the studio is set to play music from LINE 2:
    • Make sure the mixer is on (red light above the power button should be on).
    • The crossfader at the bottom should be set all the way to the right toward CH 2.
    • Above that, the CH 2 volume should be about ⅔ of the way up.
      • CH 1 should be all the way down.
    • Above that, the switch between “Phono 2” and “Line 2” should be set to Line 2.
  • You should be all set!
  • If you’d like to play music off your own computer/music player and also talk, you must talk into the black microphone that’s connected to the physical mixer. To do this:
    • The mic on the physical mixer is plugged in on the upper left (where it says “MIC”).
    • Below that you should see a switch that says “ON.” This is the switch for the mic. Keep it in the “OFF” setting until you want to talk (otherwise it will pick up your typing and any other studio noise).
    • When you’re ready to talk, flip that switch to the right to “TALK OVER” and turn the CH 2 volume to 0 (or just quieter so that you can talk over the music).
    • When you’re done talking, turn CH 2 back up to somewhere between 5 and 8 and flip the mic switch back to “OFF”

Fun times

Switching between your own computer/music player and the studio computer

  • You can use the physical mixer to crossfade between your own computer/music player plugged into channel 2 and the computer that’s plugged into channel 1! Queue some music on Mixxx on the studio computer and music on your own computer/music player. Ensure that both CH 1 and CH 2 on the physical mixer are set between 5 and 8. Use the CROSS FADER at the bottom of the physical mixer to go between them!
  • Even more fun times: Mixxx itself is a digital version of the physical mixer and allows you to have 2 pieces of music queued up that you can switch between (the crossfader on Mixxx is in the middle of the screen). So technically you can crossfade between three different things: whatever you have on your own computer/music player, and the two tracks you can queue in Mixxx. Wow, a world of possibility awaits you.

Sound effects on Mixxx

  • Mixxx has a bunch of knobs and stuff that you can use to modify the music live as you’re playing it. It also lets you do fun stuff like syncing up beats when crossfading. Experiment with the different options and see what happens!

NOTES, BUGS, AND TROUBLESHOOTING

  • When in doubt or if you encounter any problem, your first step should always be to restart the computer. When you restart, the first (and only) thing you should open is whatever program you want to play music from, in this case, either Mixxx or firefox (for music from the internet).
  • You can only play music from one program at a time in Linux. So you can’t have both Mixxx open and Firefox open for web music and switch between them. You have to pick one and go with it.
  • If Mixxx shuts down or freezes and you have to restart it, the mic may not work. In order to make it work, go to Audio Settings and check the Input settings. Set the Microphone setting to None, hit apply, and then set it to Blue Icicle again, hit Apply, and then hit OK. This should make the mic work.
  • Possible error when starting Mixxx: “Mixxx was configured without any output sound devices. Audio processing will be disabled without a configured output device.
    • Continue without any outputs.
    • Reconfigure Mixxx’s sound device settings.
    • Exit Mixxx.”
    • Choose “Reconfigure”
  • What to do if the microphone doesn’t work?
    • Check Sound Settings on the computer:
      • Click the little amplification thing next to the time in the upper right. At the bottom of that menu, choose “Sound Settings...”
      • In Sound Settings, under Input, ensure that the selected option is “Microphone: Storm HP-USB500 5.1 Headset.
        • Test to see whether it’s working by tapping or talking into the microphone and checking the “Input level” as you do that. If the microphone is working, you should see pale orange lines on the input level (they are very hard to see!).
        • If the microphone doesn’t show up as an option under input, unplug it and plug it back in.
    • Make sure volume on the microphone itself (little knob on the side of it) is turned up.
    • If all else fails, unplug it and plug it back in.
  • If nothing works or if the computer is frozen or somehow generally fubar:
    • Restart the computer and check both Sound Settings and Mixxx’s audio settings.
    • Ensure that the physical mixer is correctly configured (configuration settings for the physical mixer are below)

CONFIGURATION AND SETTINGS

Studio Computer’s Sound Settings:

  • Click the little volume icon next to the time in the upper right. At the bottom of that menu, choose “Sound Settings...”
  • In Sound Settings, under Output, ensure that “Analog Output” is selected. Mode should be set to “Analog Stereo Output.”
  • Under Input, ensure that the selected option is “Microphone: Storm HP-USB500 5.1 Headset.
    • Test to see whether it’s working by tapping or talking into the microphone and checking the “Input level” as you do that. If the microphone is working, you should see pale orange lines on the input level (they are very hard to see!).
    • If the microphone doesn’t show up as an option under input, unplug it and plug it back in.

Mixxx Settings:

  • With Mixxx open, mouse to the very top of the screen (to the right of where it says “Mixxx” in the very upper left of the screen). Click “Options.” Under options, go to “Preferences.” On the preferences page, under “sound Hardware,” the Input tab should have:
    • Sound API: ALSA
    • Sample Rate: 48000 Hz
    • Latency: 21.3 ms
    • Output: Master: HDA Intel: ALC888 Analog (hw:0,0) and Channels 1-2
      • All others should be “None.”
    • Input: Microphone: Blue Icicle: USB Audio (hw:1,0) and Channel 1
      • All others should be “None.”
      • NOTE: If Blue Icicle isn’t an option for the Microphone setting, make sure it’s plugged into the usb port in the back of the computer. If it is plugged in, unplug it and plug it back in.
      • NOTE: When Mixxx first starts up, even if the Microphone setting is correct, the mic may not work. Set the microphone setting to None, hit apply, and then set it to Blue Icicle again, hit Apply, and then hit OK. This should make the mic work.
      • NOTE: If you had to unplug and plug the microphone while Mixxx was already open, it may not recognize the mic. Unfortunately, you will then have to close and re-open Mixxx. When you re-open it, go to Options >> Preferences >> Input and set the Microphone to Blue Icicle: USB Audio (hw:1,0) // Channel 1

Livestream Settings

  • Check that the stream is running by going to http://radio.sudoroom.org/ and clicking the GREEN button that says Radio Room Stream. This will take you to http://nthmost.net:8000/rpi.
    • NOTE: You should either do this on a separate computer or if you’re doing it on the studio computer, please note that you will probably have to restart after checking whether it works.
    • If you get an error (“The file you requested could not be found”), restart the raspberry pi which runs the livestream (this is a very small computer located on the top shelf of the wooden end table. You restart it by unplugging the wire on its right and plugging it back in. After you unplug and plug it back in, wait 30 seconds and refresh the livestream page. If it still gives you an error, alert someone!!!
  • To ensure that Mixxx is properly streaming to the livestream, first open Mixxx and mouse to the very top of the screen (to the right of where it says “Mixxx” in the very upper left of the screen). Click “Options.” Under options, go to “Preferences.” On the preferences page, on the left, click “Live Broadcasting” (the last option on the left).
  • Settings should be set as follows:
    • Type: Icecast 2
    • Mount: /sudoradio.mp3
    • Host: radio.indybay.org
    • Port: 80
    • Login: source
    • PW: I forgot the PW :(
    • Stream settings:
      • Public Stream should be checked
        • Stream name: Sudo Radio
        • Website: http://sudoroom.org
        • Description: Sudo Radio - Live from Downtown Oakland
        • Genre: Hacker
      • Encoding:
        • Bitrate: 192 kbps
        • Format: MP3
        • Channels: Stereo

Physical Mixer Settings

On the back of the mixer:

  • “Input” Line 1 should connect to the computer’s lighter green audio port.
  • “Input” Line 2 should connect to the free-floating 1/8th inch cord that has an orange duct tape thing on it that says “LINE 2”
  • Input Phono 1 & 2 should be empty, but these are available for additional connections!
  • Output Amp should connect to Input L & R on the tiny box pasted to the front of the wooden table
    • This tiny box is the digital audio interface (http://en.wikipedia.org/wiki/Digital_audio) which means that it converts analog sound (analog sound comes out of the physical mixer and goes into the interface) into digital sound (analog sound goes into the interface and digital sound comes out of the interface to fly into the internet). The other end of the interface connects to the Raspberry Pi which is a tiny computer that only send the sounds that we produce through the mixer into the internet via the livestream.
  • Output Rec should be empty.

On the front of the mixer (start on the top right and go down, then start at the top of the column second from the right and go down, etc.):

  • Power: Always on (red indicator light should always be on)
  • Treble, bass, and master: all at 0
  • Ch 2 Start/Mute Switch: Start
  • Phono 2/Line 2 Switch: Line 2
  • Ch 2 (Volume): between 5 and 8
    • Do not set this all the way up as this will likely damage the speakers and create distortion.
    • Adjust levels as necessary - some things may be loud, other soft. When you plan to speak, turn down the channel volume.
  • Cross Fader: Set to Ch 2 when using the Line 2 cable to your personal computer/music player and set to Ch 1 when playing audio off the studio computer.
  • Ch 1/Ch 2 Cue Switch: Doesn’t matter.
  • Phono 1/Line 1 Switch: Line 1
  • Ch 2 (Volume): between 5 and 8
    • Do not set this all the way up as this will likely damage the speakers and create distortion.
    • Adjust levels as necessary - some things may be loud, other soft. When you plan to speak, turn down the channel volume.
  • Mic (top left): Black mic should be plugged in
    • Off/Talk Over Switch: Set to Off except when you plan to speak into the black mic. When you’re ready to talk, flip that switch to the right to “TALK OVER” and turn your current channel volume to 0 (or just quieter so that you can talk over the music).
    • When you’re done talking, turn CH 1 back up to somewhere between 5 and 8 and flip the mic switch back to “OFF”
    • NOTE: The black mic is the only mic you can use when you are playing your own music off the Line 2 cable to your computer/music player, but you can technically use it anytime.
  • Mic Level: 0
  • Cue Level: Doesn’t matter
  • Ch 2 Start/Mute Switch: Start

Speaker Configuration:

  • The speakers in the room should be connected to the right of the digital audio interface (the little box taped to the front of the wood stand). This allows you to hear exactly what goes onto the livestream.
    • If you need to test whether the studio computer is producing sound, you can plug speakers (preferably another set of speakers so that we don’t forget to plug these back in to the interface) into the light orange port on the back of the studio computer.
    • If the speakers won’t turn on, ensure that the power strip that they are connected to is turned on. That power strip is hidden behind the wood stand.


How do I record and produce audio in the studio?

We currently use Audacity to record content. Detailed instructions will be forthcoming, but in the meantime, you should check out a lot of the great existing tutorials on Audacity that are already online.

Old Stuff

Old stuff from when we were setting up the radio is at Sudoradio