### ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

## 1aSC32. A computationally efficient articulatory synthesizer.

**Jacob Rael
**
James Chang

Abeer Alwan

**
**
*Dept. of Elec. Eng., 66-147E Engr. IV, UCLA, 405 Hilgard Ave., Los
Angeles, CA 90095
*

*
*
In this study, a computationally efficient articulatory synthesizer that
utilizes the popular analog circuit simulator SPICE is developed. The
synthesizer uses a transmission-line analog model of the vocal tract. An analog
model has many advantages over digital representations: (1) Side branches
(needed for modeling nasals and /l/) can be simulated easily by additional
transmission lines in parallel; (2) drive-dependent sources, at any location,
could be added; and (3) the number of sections can be varied without changing
the sampling rate, as is the case with a digital synthesizer. A computer
interface, using MATLAB, is developed such that the input to the synthesizer
can be specified in terms of the area function of the vocal tract and the type
and location of dependent or independent sources (voltage or current.) By
simulating the transfer function of the vocal tract, transient and steady-state
responses are generated. Using Fant's vowel area functions (1960), vowels were
synthesized with their first four formant frequencies almost identical to those
given by Fant. The feasibility of implementing the analog synthesizer using
modern ICs, such as the gyrator-based inductance simulator and switched
capacitor filter circuits, is assessed.