On Exploring Vocal Ornamentation in Byzantine Chant

Abstract

A special vocal ornament in Byzantine chant (BC), the single cycle ornamentation structure (SCOS), is defined and compared with the vibrato with respect to its time (rate, extent) and spectral (slope [SS], relative speaker's formant [SPF] level, formant frequencies [Fi] and bandwidths [Bi], and noise-to-harmonics ratio [NHR]) characteristics. This is a comparative study between the vocal ornaments of SCOS and vibrato, of which time and spectral acoustic parameters were measured, statistically analyzed, and compared. From the same hymn recordings chanted by four chanters, the SS, SPF level, FFi, FBi, and NHR difference values between the vocal ornament and its neighbor steady note, and the rate and extent, were compared with those of vibrato. The mean extent values for SCOS were found to be almost double the corresponding values for vibrato, and the rate of SCOS tends to be different from the rate of vibrato. The difference values of: 1) the NHR, 2) the spectral slope, and 3) the SPF level, between the vocal ornament and its neighbor steady note were found to be: 1) higher for SCOS, 2) mainly lower for SCOS, and 3) lower for SCOS, respectively. No significant differences were detected for the FFi and FBi. The FF1 differences tend to be negative in both ornaments indicating a formant tuning effect. A new vocal ornament (SCOS) in BC is studied, of which the extent, NHR (HNR), the spectral slope, and the SPF level are different compared to those of vibrato.