This stack was written by Peter Ladefoged with the help of a number of students as instructional material for a course in experimental phonetics. The aim of the stack as a whole is to enable students to understand the basic concepts of acoustic phonetics, and to go on to more complex topics, such as the relation between damping and bandwidth, and the nature of an FFT analysis.
The program Vocal was originally devised in order to help us assess the acoustic results of different articulatory gestures. We want to know the acoustic structure of the sounds that the brain tells the vocal organs to make. Of course, we do not know how the brain works, but we can make plausible guesses concerning the way in which the vocal organs are controlled. Ultimately we would like a system that starts from discrete units that specify articulatory movements, and joins them into continuous speech. The present Vocal system does not contain such a module, but it is built in such a way that it could be easily added. Modeling articulatory-acoustic relations remains the prime function of the system; but there are now additional components that enable us to estimate, very roughly, possible articulatory causes of acoustic data used as input, and also to do rudimentary synthesis of vowels and phrases directly from formant data.
MacSynth is a program for synthesizing speech given either numeric values (which can be in a file) or free-hand drawn values, for formant frequencies and amplitudes, and amplitudes of the fricative components. This program will not play speech on the SE/30 or on the MacIIx, IIcx or II.P
PlotFormants is a Macintosh program which generates two-dimensional plots of formant frequency data on linear, Mel and Bark scales.
Joaquim Llisterri, Universitat Autònoma de
Barcelona
Last modified: 21/8/03 21:09