Thursday, October 24, 2013

mobile live audio streaming with a Raspberry PI

From time to time i get obsessed with non-stationary audio streaming, esp. in the context of the radio aporee continuous stream. As you may know, this station plays random selections of the 20000+ recordings from the aporee soundmap, but also reacts and interferes with listeners, activities in the field and a couple of live microphones from the locusonus project.

The broadcast box is one of the experimental tools to engage with sound in public space, it directly hooks onto the current broadcast and allows to play inbetween places, situations and archive recordings, right where you are at the moment. However, it's quite a bulky bunch of gear to carry around.

This setup is he latest of my experiments in that field. The unit left is a Raspberry PI, a little 40€ pocket size computer running Linux, connected to a USB battery which lasts for a day, and an Olympus LS5 recorder connected to the PI via USB. The stick attached to the PI is an UMTS/3G modem for mobile Internet access.


In short, this assembly is a complete mobile radio broadcast unit, which allows to send live sound in crispy stereo to radio aporee (or elsewhere), on-the-go. Of course, without a network the whole thing is pretty useless...

I still have to do some elaborated tests, and have to improve reliability, but the concept already seems very promising. If you are interested in tech details, let me know. tbc.

edit Sat. Nov. 2nd :

today i did a short test while washing my stuff in the laundry at Ohlauer Str, Berlin Kreuzberg. it worked pretty well it seems, got some feedback from listeners. with the stream2archive recorder on aporee.org i made two 15min. snapshots of "the show":

laundry, Berlin Kreuzberg, part 1:

laundry, Berlin Kreuzberg, part 2:



6 comments:

  1. Great idea! Can you post more details? What did you use to build the Rasberry Pi and where did you get those cool cables? Just a thought but you could set up a speaker somewhere with a Barix Extreemer http://en.wikipedia.org/wiki/Exstreamer

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  2. i think i'll summarize the setup details, configs etc. the other day, a bit tight om time actually. the spiral cable came with the battery, have to check if it's a full functional usb-cable. the raspi runs plain raspbian linux, had to setup wifi, UMTS, and compile the darkice streaming software myself. but altogether not a big deal, when familiar with linux... --u

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  3. great! Is the Tascam acting as a class-compliant usb audio interface, then?

    Interested in details.

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    1. it's an Olympus, it seems that class-compliant usb devices work. tested also Zoom H2 and a Behringer usb mixer. on Debian/raspbian you can check with lsusb and arecord -l. darkice, the streaming software on the PI, uses then hw:1,0 as the audio device name.
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  4. Great idea! In my first project I'm going to show you how I setup multi-room audio that can be controlled by any device with a web browser or an app on your Android and/or iOS device. Thanks and keep updating! If you are looking for a live local audio streaming app? Mappstream will lead the way! It’s amazing. More insights to the app can be found here:

    https://itunes.apple.com/us/app/mappstream/id735066334?mt=8

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