Effects of pitch, intensity, and timbre on frequency masking

Abstract

It has been widely known that the four main factors of music—pitch, timbre, duration, and loudness—are not independent. One comes to wonder how these four factors will affect frequency masking, which has traditionally been explained with the cochlear responses to pure tones or narrowband noises. As a first step toward understanding these interactions, the mutual masking effects of two concurrent non-unison tones were investigated. A MATLAB simulation was implemented based on the psychoacoustic model in Bosi & Goldberg (2003). As the degree of masking would obviously depend on factors such as pitch, timbre, and intensity, we considered 81 pitches (B0 to G7) in three timbre categories (pure tone, uniform, and average timbre). For each timbre category, 15 levels of amplitudes were considered to examine the effect of intensity. A preliminary analysis shows that the chance of the higher pitched tone masking the lower pitched tone might change depending on the pitch, timbre, and loudness. The findings will be discussed with the implications on the interpretation of high voice superiority on the preference of melodies on the highest part in music.