Quality evaluation standard research of vowel singing in vocal music

There is no standard of quality evaluation for singing in the world, the answer of a singer´s singing is good or not, traditionally, is determined by a professional expert´s ear and personal sense, the purpose of this paper is to find the solution, the experiment approach is proposed, the different vowel training singing and speak vowel voice are analyzed from time-domain and frequency domain, the results show that time domain smooth and frequency domain periodical square wave vibration are the objection of a good vowel singing, which is helpful of quality evaluation standard for vocal music.