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+Android Audio Quality Verifier App
+==================================
+
+This app runs a set of audio quality tests on an Android device,
+to verify the end-end sound recording path.
+
+If any of these tests fail, the device is probably unsuitable
+for demanding audio tasks such as speech recognition.
+If all the tests pass, the device audio is of a good standard.
+Note that not all possible audio defects can be detected by this
+test suite, so passing does not guarantee ideal audio quality.
+
+Hardware setup
+--------------
+
+The required physical set-up consists of a powered speaker,
+connected to the Android's headphone output by a standard
+audio cable.
+
+For loudspeakers which come in pairs, you only need to use
+one speaker (typically the powered or master speaker); you
+can leave the second speaker disconnected.
+If the speakers are stereo within a single unit (sometimes
+with speakers facing in opposite directions), place the phone
+in front of either of them.
+Speakers with multiple drivers per channel (e.g. a tweeter
+and a woofer) are not suitable.
+
+The phone should be placed in front of the centre of the
+speaker cone. The distance from the speaker will be adjusted
+during calibration; typically you could expect it to be around
+3cm or so.
+Use a supporting platform such as a stack of books to raise
+the phone to the correct height to line up with the speaker.
+
+Bluetooth connection is possible but cable connection is
+usually preferable.
+
+Recommended loudspeakers
+------------------------
+
+Using suitable loudspeakers ensures that test failures highlight
+problems with the Android device under test, and not limitations
+of the loudspeakers. The following loudspeakers work well for this
+purpose:
+
+1. Yamaha NX-B02
+
+Use on AC power, not batteries.
+This speaker works well with Bluetooth as well as a wired connection.
+Note that it's not uncommon for the devices to exhibit different
+bugs under Bluetooth.
+
+2. Cakewalk MA-7A (Edirol / Roland)
+
+The "Bass Enhancer" feature MUST be switched off.
+Note that it turns itself on again every time the speakers are
+powered on, so it is easy to forget to switch it off!
+
+Software setup
+--------------
+
+1. Build the application's apk.
+2. Install the apk using adb.
+3. Run the app.
+4. Click "Calibrate". Position the phone as described in
+ Hardware setup above, with the microphone facing the speaker,
+ and adjust the volume of the speaker until the status message
+ indicates it is correct.
+5. Click on any test in the list to run it, or "Run All" to run
+ each test in sequence.
+6. Click "Results" to view the outcomes. A correctly functioning
+ device should pass all tests.
+7. Click "Send by email" from the results page to send the
+ results to an e-mail address of your choice. The recordings
+ made are also attached as raw 16 bit, 16 kHz audio files to
+ help you diagnose any failed tests.
+
+Q&A
+---
+
+Q. What if the sound level check fails?
+A. Go back to the calibration step before running any other test.
+ Make sure the device has not been moved.
+ We also recommend that once the setup is calibrated there are no
+ moving objects or people near the device under test, since these
+ will change the acoustic properties of the environment from the
+ calibrated state.
+
+Q. Some of the tests sound very loud. Is this normal?
+A. The clipping test will generally be very loud indeed;
+ the others should be at a moderate volume.
+
+Q. What sort of room should the tests be performed in?
+A. Any, as long as the background noise levels are kept low, to
+ avoid interference with the test recordings.
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