A Comparative Study of the Non-nasal and Nasal Voice in Hindustani Vocal Music

A nasal voice is a type of speaking voice characterized by speech with a nasal quality. For those who sound nasal, air comes through the nose caused by limited space in the back of the throat. In that case the naso-pharyngeal cavity is connected to the oral cavity by the opening of the velum. Role of nasality in Hindustani vocal music is controversial, since most of the schools refer to it as an error. In this study we have tried to see the acoustic changes which occur during rendition of two ragas by two different singers in both oral and nasal voice. A database consisting ten signals, sung by two singers, out of which five signals were of the raga Bhairav and the other five signals were of the raga Darbari was taken. Each singer sang the same phrase of the given raga firstly in their normal voice and added nasality gradually to the rest four signals in an increasing order. Three formants (F1, F2 and F3) along with the pitch and the notes were extracted from each of the ten signals and the spectral cues were studied for both normal and nasal singing. Notes were extracted from the steady state pitch values. The variation of amplitude with frequency was studied.