Projects:2018s1-192 Karplus-Strong Synthesis of Sound
Project Team
David McQueen
Samuel Churches
Sam Haberman
Supervisors
Dr Andrew Allison
Dr Brian Ng
Introduction
The Karplus-Strong plucked-string algorithm was a computational model developed in the early 1980s as an efficient model for vibrating strings based on physical resonance. It was praised for the rich and realistic timbres it generated despite its simplicity. Briefly explained, the algorithm works by placing a delay element into a feedback configuration together with a simple filter. Noise sources inserted into the feedback loop will resonate in the system at a set frequency and decay away due to the action of the filter.
Since its conception, many advances have been made in developing the algorithm in efforts to generate more realistic models of instruments and to widen the range of instruments available for simulation through advances in the theory of digital waveguides for the modeling of multi-dimensional systems. Efforts have been made to produce musical synthesizers as products, with patents being applied for in 1986 and 1987 and both Mattel and Yamaha licensing the technology however no products have been brought to market using the algorithm from these efforts.
Some hardware digital modular synthesizers are available that provide sufficient building blocks to run a Karplus-Strong model although these synthesizers do not support chromatic tuning of the model and so are not as easy to use as synthesizes based on other techniques that support a MIDI style interface to playing the synthesizer. Additionally, analog synthesizers based on the Karplus-Strong algorithm have been released as products however they to do not support chromatic tuning.
Abstract
The goal of the project is to develop two synthesizers based on the Karplus-Strong algorithm. The first will implement the model using analog electronics, with digital electronics to control it and the second will be purely digitally based. The synthesizers will be required to be playable using a MIDI controller (such as a keyboard) and have a user interface that allows the character of the generated music to be intuitively adjusted.
The three main research goals of this project are to:
