Idea for this project

As I searched for an idea for this project, I asked myself what kind of object or software I could create that I would be inclined to use in my musical creations. As I sometimes like to play ambient music with synthesizers, I thought that I could create a synthesizer engine and a controller to create unnatural ambience sounds easily. I came up with the idea of a musical drone generating engine, combining different kinds of synthesis techniques and tailoring itself to the room it is located in.

Objectives

• Create a sound engine combining different sound synthesis techniques to generate interesting sounds but also to solidify my understanding of these techniques I learned in the MUMT 203 course this very semester.

• Use the Arduino to control different parameters of the sound to become more comfortable with this object and its programming environment.

• Use different sensors so that the room have an impact on the sound generated.

• Design an unusual controller so that the user have to think outside of the equal-tempered musical system to use this synthesizer

Design

This project is composed of three important parts: the sound engine, the controller and the effects. The sound engine and the effects have been implemented using Max/Msp and the controller have been built around an Arduino. The sound engine is composed of five different sound synthesis engines added together. The first such engine is an additive synthesizer that uses 8 different cycle~ objects, which are used as oscillators. They are all used to generate the main frequency inputted and overtones of this frequency, that are sometimes harmonic and sometimes not at all. I designed 5 presets for this engine to use it more easily, but the user can also create its own sound by playing with the overtones multiplicators, the phase offset parameter and the amplitude envelopes.

There are multiple effects available in the main patch of this synthesizer. They are overdrive, chorus, reverb, a low-pass filter, a resonance filter and a noise engine. Except for the low-pass filter and the noise engine, all of those effects have a dry/wet control to make them easy to use. The overdrive, low-pass filter, resonance filter and noise engine were implemented using the already implemented Max objects for these effects, but the reverb and chorus needed to be "created". For the reverb, I used the Schroeder Reverberator designed by John Chowning that is available on the website of the Center for Computer Research in Music and Acoustics of Standford's University that you can find right here: https://ccrma.stanford.edu/~jos/pasp/Schroeder_Reverberators.html

The last part of the design of my project is the controller. This controller measures various parameters of the room and shapes the sound by controlling the effects. There are in total four sensors actively feeding data to the synth engine. The infrared receiver calculates the distance between itself and an object or a surface, ranging from 2 cm to 400 cm. This sensor has control over the reverb applied to the sound since reverb is a function of the room size and shape in which a sound is produced. That way, a larger room will generate a sound with more pronounced reverb, where a smaller room will produce a dryer sound. There is a pressure variation sensor that raises the gain slider of the noise generation engine, such that there is a possibility to blow on this sensor to add noise to the sound generated, or the user can make the room pressure increase somehow (I personally put my finger on top of the sensor) to add noise to the sound generated by the engine. A photoresistor is set up such that it controls the cutoff frequency of a low-pass filter. So, using this synthesizer in a place with more light will yield a brighter sound where a dark place will only produce low-end frequencies. The last sensor senses humidity and temperature. It is set up such that the humidity percentage of the room controls the dry/wet parameter of the chorus effect and the temperature measurement controls the dry/wet parameter of the overdrive effect. The controller also features a joystick and a button. The button only serves the purpose of changing the preset of the additive synthesis engine. The joystick records values for the positioning of the part you can move on the X-axis and the Y-axis as well as the state of the built in button. It is set up such that the Y-axis, when the button is not pressed, controls the modulation frequency, which is used in the Frequency Modulation engine, the Ring Modulation engine and the Amplitude Modulation engine, the X-axis, when the button is not pressed, controls the modulation index of the Frequency Modulation engine, the Y-axis, when the button is pressed, controls the main frequency the synthesizer is supposed to produce and finally the X-axis, when the button is pressed, controls the length of the amplitude envelopes of the additive synthesis engine. It is to be noted that in the main patch you can observe at the top of this page, the part of the patch that deals with the incoming data from the controller is a modified version of a patch that was given in the MUMT 306 course called "arduino_2in.maxpat".