I am afraid PRI sensors will be too accurate given the parameters of the project. The pressure mat sounds interesting. I found some mainly on home surveillance sites but I wonder how I would separate the different sound files and sensors inside the mat. I am assuming the pressure mat as sold from the store will only have one sensor, whereas I will need 4 to 6 since each sensor leads to a different sound file. If this can be done, then this would due the fastest and cheapest solution.
However, if it cannot, the MP3 player shield would be an ideal contender...... Has anyone used this before? How is it different from a SD/MMC card with a wave shield?
Thank you!!!!!