Raspberry Pi Does Sonos – Part 2 – Transmitting on AirPlay

In the first part, I talked a bit about setting up the Raspberry Pi as an AirPlay receiver; something that can receive audio streamed over a home’s wifi connection and play it.

Transmitting from Apple

Apple Devices already support AirPlay by default (not a shock – it’s an Apple invention). So to connect an ipad, iphone, itouch etc… is straightforward. You simply double swipe up in IOS7 and enable AirPlay in the control panel. Job done.

Transmitting from Windows

Windows can be made to talk to the Pi using a program called Tuneblade. This is an application (that if you’re streaming to Shairport as described in Part 1, is free) and can be downloaded from http://tuneblade.com/.

Once launched, Tuneblade can be accessed from your system tray and includes a volume control, so remember to turn it up! It streams the audio even if you mute the local audio output – which is handy if you don’t want to listen to your tiny PC speakers.

Transmitting from Android

On Android, some app’s (such as Streambels) support direct streaming to AirPlay – but many popular apps do not, for example, Spotify does not. Similarly, TuneIn the radio app doesn’t. So another solution is required, similar to that used on Apple devices. ie: redirect the entire audio stream of the device.

There are a number of Apps for Android that will stream the entire sound output of the phone to the Pi. For example, one called AirAudio and another called AirStream. Both of these have demonstration versions to allow you to test. However you will have to buy a licence for around £4 to get a permanent solution (ie: one that doesn’t switch itself off after 10 mins). I didn’t find a totally free alternative (and I’m not anti paying software developers in any case!!).

Whilst apps like Streambels that only stream their own audio channel don’t need root privileges, these other applications that give the greater flexibility of sending any audio on the device (such as that coming out of Spotify) by effectively snooping on other applications audio output – do require root access / super user privileges.

This gets you into the exciting area of device rooting. The process for this can be complicated and in many cases results in the device being wiped as one of the steps to do it. This was certainly the case for the house Nexus 7 though happily not my Motorola Atrix phone. Doing so, however gets this solution to work. In addition it also provides access to a variety of other very useful apps including backup tools that can backup application data as well as the install apk’s and much more. Rooting an android device is not for the feint hearted and comes with associated risks of bricking the device and invalidating your warranty. So something you do, at your own risk.

Transmitting to Multiple Zones

By setting up multiple Raspberry Pi’s around the house with different device names you can effectively zone the house into different audio areas. In addition many of these transmitting programs can broadcast to more than one AirPlay receiver at once. In our house, with our network setup, solely using Raspberry Pi’s, they seem somehow to sycnhronise which is very cool for parties!!!