Adafruit Wave Shield for Arduino
The wave shield is working! As this was my first attempt at soldering, I encountered some issues. The main one was that the tip of the soldering iron was not producing enough heat to melt the solder. After many attempts (including melting the circuit board and placing an order for a higher quality iron), I changed the tip of the iron. This did the trick and I managed to solder the components to the board with relative ease.
In order to get an audio sample, I a text to speech tool (http://www.fromtexttospeech.com/). This reads any speech necessary and provides a downloadable .mp3 file. This file needs to be converted to a .wav file, shrunk to 22kHz, mono output and 16-bit for the wave shield to recognise it. These files are then moved to a SD card, which is inserted into the shield.
At this point, I have the shield playing audio. Next, I need to pair the sensors with the shield and allow their inputs to trigger the audio output.