Project has been discontinued

This project has been discontinued. The work will continue in the AMTOOLBOX project, also available on sourceforge.

The software in this project is completely functional, it is just not being updated. Therefore, it also only contains the old CASP models, and not the current model. To get the newest version, please send an email to Morten Løve Jepsen at the Centre of Applied Hearing Research, Technical University of Denmark.


The Computational auditory signal processing and perception (CASP) model can account for various aspects of simultaneous and non-simultaneous masking in human listeners. The model is based on the modulation filterbank model described by Dau 1997 but includes major changes at peripheral and more central stages of processing. The model contains outer- and middle-ear transformation, a nonlinear basilar-membrane processing stage, a hair-cell transduction stage, a squaring expansion, an adaptation stage, a 150-Hz lowpass modulation filter, a bandpass modulation filterbank, a constant-variance internal noise and an optimal detector stage. The model was evaluated in experimental conditions that reflect, to a different degree, effects of compression and spectral and temporal resolution in auditory processing. The experiments include intensity discrimination with pure tones and broadband noise, tone-in-noise detection, spectral masking with narrowband signals and maskers, forward masking with tone signals and tone or noise maskers, and amplitude modulation detection with narrow and wideband noise carriers.

The CASP model has been developed at CAHR.

The toolbox is Free software, released under the GNU General Public License (GPLv3).


You can read the documentation included in the M-files online

A Design guideline can be found here.