Last Christmas I built a Quiz Buzzer System for my mother. She is a big fan of television quizzes and love to organize some with her friends and family. The particularity of this project is that you can choose your team buzzer sound from a list of more than 30 digital sounds.
The system is composed of a main console, 8 buttons, a power supply and a set of telephone cables. The core of the console, built in a plastic project box, is made of an Arduino Duemilanueve micro-controller coupled with an Adafruit wave shield. The 8 buttons are made out of small project boxes and arcade buttons, again from Adafruit. The buttons are connected to the main console using telephone jack and cables.
Adding quality audio to an electronic project is surprisingly difficult. Here is a shield for Arduinos that solves this problem. It can play up to 22KHz, 12bit uncompressed audio files of any length. It’s low cost, available as an easy-to-make kit. It has an onboard DAC, filter and op-amp for high quality output. Audio files are read off of an SD/MMC card, which are available at nearly any store. Volume can be controlled with the onboard thumbwheel potentiometer.