OBJECTIVE

Make a sensor from a microphone that measures/detects an environmental condition that is not an audio source. You must convert some other physical energy (displacement, light, electricity, heat) to sound to be sensed by your microphone :

DETAILS

The first week of the project will be follow these steps:

1) Identify the source that you are converting to audio. This may be a human interaction like a button push, or it may be an environmental condition such as wind speed or temperature. For the sake of describing an approach we will use a button press as our example input in the style of Valkyrie Savage’s Lamello.

2) Convert the energy into sound. For the button press I would take the following steps, create a set of tines that get plucked as the button is depressed (see this video of a finger piano), connect those tines to a resonant chamber, and place an electret microphone in or on the chamber.

3)Transform your incoming signal to the frequency domain using an FFT to gain visual confirmation that you can differentiate the signal from noise.

Projects

• Acoustic Barcodes
• Lamello
• Acoustruments
• SpectraScreen
• Scratch Input
• Floor has a voice

Tutorials

• Jesse Stiles DSP tutorials for Max (particularly chapter 08 and 09)
• FFT
• Paul Bourke’s Post on DFT and FFT
• Adafruit Electret Microphone

Base Code

• Photon fft/tcp
• Processing tcp example

DELIVERABLES

The initial prototype is due Thursday, February 4th.

A working mechanism with the associated FFT displayed on your laptop is required.

Banner image is from Daniel Sierra’s Oscillate