So, this month I've decided to (re)explore Arduino and various sensors in conjunction with Max. I've been doing this for quite a few years and have always gotten something out of it, but regrettebly, I've never really explored things further. So as a result my knowledge in this area has remained restrcited to a few simple processes.

I must admit I'm starting out with a very simple process, whereby a pure wave oscillator (fixed at 330Hz) has its amplitude modulated by marginal variances of light intensity. The light intensity is measured by a little Freetronics light sensor which outputs a value of 0 > 1027. I've programmed the Arduino to read every 5 seconds. This value is then received by the Serial and scaled/converted in Max.

The modulation rate is informed the differential between the previous and current light intensity value: so if the previous light value was 624 and the current value is 627, the differential is +3. This value is then multiplied by 0.1 so that it it becomes 0.3. This modulation value is then routed to the pure wave oscillator - i.e. 330Hz with an amplitude modulation rate of 0.3Hz.

I've also used the differential to control the parameter of a second pure wave oscillator. This second oscillator has a set fundamental of 440Hz, but in this instance the differential value will control the fundamental frequency instead. So, if the differential is +3, then the second oscillator with be 443Hz.

As the light sensor provides a read every five seconds, this allows differences in amplitude rate and frequency to be observed.

The audio is an excerpt of a recording made in the studio on Sunday morning.

Tags: light sensor, pure waves, simple, week 13 2018, View by:Tristan Louth-Robins