The pre configured SD Card reveil-pi comes with Darkice installed and set to connect and begin streaming when the Pi starts or restarts.
The default is a mono stream to the Locus Sonus server called reveil_test.ogg. You can listen to the stream by going to the Locus Sonus soundmap and choosing 'i' from the upper right, then 'server'.
To appear on the map, set up an account at Locus Sonus: from the Locus Sonus soundmap choose 'i' from the upper right, then 'log in'. From the login page choose 'open a new microphone..'. You will receive a confirmation email and the new account will shortly be validated - usually within a day. You can then log in and input your location and other settings.
For the stream to appear on the map, the settings in your Locus Sonus account must match the settings used by Darkice - see below.
With the disk inserted and the Pi up and running, it will appear in the OSX Finder window as "reveil-pi".
Click Connect and log in with the Username "pi" and the Password "soundcamp"
In "Home Directory/Desktop" locate the folder "stream_settings" containing the file "stream_configuration.cfg". Control-Click and choose to open it with Text Edit or another editing application.
(You may want to make a backup of this file: Choose File > Duplicate and Save the resulting copy as something like "stream_configurations_backup.cfg" in the same folder as the original, or somewhere convenient.)
The file "stream_configurations.cfg" contains a list of parameters for the stream generated by Darkice. You need to update the following:
Change the mountPoint currently "reveil_test.ogg" to the details of your stream: something like "london_camberwell.ogg". To check the name of your stream, log in as above: your stream name is reported at the upper left.
If you want to stream in another format, such as MP3, the file extension will be ".mp3" and you will need to change the line "format" to "mp3" (currently "vorbis"). In this case, you should also adjust the stream type in you account settings. Otherwise, you can leave these as they are.
In the second paragraph of settings, labelled [input], you choose to stream in mono or stereo, depending on the soundcard you are using.
For a Mono stream, you should set the line "channel" to "1". You should normally then set the line sampleRate to 44100 Hz and the bitrate to 16. A typical mono soundcard would be the Icicle from Blue Microphones.
For a stereo stream, the line "channel" should be set to "2". You can normally keep the sampleRate at 44100 Hz and bitrate at 16.
Quality settings: if using variable bitrate (the default), the data throughput of the stream and its consequent quality, are set on a scale from 0.1 to 1.0 with 1.0 being the highest quality. We suggest starting at 1.0 and scaling back until you have the best signal you can obtain without dropouts. In London over adsl we can stream stereo at quality setting 1.0. In Tanzania over 3G we typically scaled back to 0.4. Listen for dropouts and adjust as necessary. For changes to take effect, you will need to reboot the Pi - see below.
You can optionally add "name" "description" "genre" and a reference URL.
When you're done, Save the file and Close it.
For the changes to take effect, you need to restart the Pi. Simply unplugging the Pi can damage the SD card. In our experience, the Pi is resistant to damage from planned or unplanned power outages. But the general advice is to avoid these. Aim to use the more roundabout method described here:
Once the Pi has restarted, it should appear again in the Finder sidebar, and the stream should appear on the Locus streammap. It will also still be available on the server list (i then server, as above).
If your stream does not appear, it may be because the details entered above do not match the ones in your account settings. You should have an email from locustream support
The final thing you may need to adjust is your sound settings. The Pi runs on Linux and uses an audio system called Alsa to handle the incoming audio from the microphone and soundcard. You many need to confirm that your chosen soundcard is selected, and adjust the level of gain.