Real-time dissonancizers: Two dissonance-augmenting audio effects

Matthew Hoffman; Perry Cook
DAFx-2008 - Espoo
We present two simple perceptually motivated audio effects designed to increase the perceived sensory dissonance/roughness (a process we call “dissonancization”) of audio input. The first involves heterodyning multiple bands of the audio signal at different frequencies to break each sinusoid in each band into two sinusoids separated in frequency by the amount that Kameoka and Kuriyagawa [1] predict will produce a maximally dissonant effect. The second attempts to increase the depth of modulation caused by existing beating partials by exponentiating the amplitude envelope within small bands, enhancing the perceived roughness already present in the signal. The first algorithm can produce very dramatic effects even for very consonant inputs, whereas the second tends to produce a more subtle effect. Both algorithms are quite simple to understand and implement and computationally inexpensive enough to be used in real time, but produce perceptually interesting results. The effects can be selectively applied so as to affect only desired frequency ranges, and can be continuously controlled (e.g. in a performance context) to have more or less impact.