I am building a fake storm shelter bulkhead door for a camp at Burning Man. I want the action of opening the shelter door to engage an audio track which will play the sound of the wind. When the door opens the volume will be at its lowest but as the arc of the door increases the volume will also increase. Secondly, when the door is replaced to its resting position I would like it to cycle to another audio track. Can someone help me with how I might best achieve this?
A simple contact switch should work for detecting the initial opening, and final closing of the door. Or use magnetic reed switches, like some of the alarm systems do. For the volume control, you need to measure the angle of the door. That can be done various ways too. A standard volume control/potentiometer will work, if you can mount it such that the door movement turns the shaft. A linear pot might be easier to interface. Various distance measuring options could be used as well, if you want to use a microcontroller to read them and process the information.
Thank you so much, Phil_Duby. I am a complete novice at these things but I am very excited to start the learning curve. I really appreciate your help.