Acoustic characteristics of European-American and Latin-American male adults during oral reading and sustained phonation of vowels

Previous research has shown that differences exist in acoustic characteristics as well as in physical characteristics between ethnic groups. Few studies have been conducted in this area of voice research. The Hispanic ethnic group has received considerably less attention than the African-American and European-American groups. If the Hispanic population continues to grow as expected, this group will become a large percentage of the American population. In order to properly identify, diagnose and treat voice disorders in this population it is imperative to know the different parameters of a normal voice.

The purpose of this study was to determine whether differences exist in acoustic and physical characteristics between Latin-American male adults, a large subgroup of the Hispanic population, and European-American male adults. In particular, this study compared speaking fundamental frequency during oral reading, fundamental frequency of a sustained vowel, semitone range, and formant frequency. Ten Latin-American and ten European-American male adults, ages 18 to 35 years, performed both oral reading and sustained vowel tasks. The European-American subjects were age-matched to the Latin-American subjects. The height and weight of the subjects were not matched. However, height and weight were measured and compared to ascertain whether these physical characteristics have any correlation to acoustic differences.

The results showed significant differences in physical measurements and acoustic characteristics between the European-American and Latin-American ethnic groups. The Latin-American group was significantly shorter in standing height and sitting height. The Latin-American group was lower in weight, although not significantly. Semitone range was significantly smaller in the Latin-American group than in the European-American group. The second formant frequency of the vowel /u/ was significantly lower in the Latin-American group than in the European-American group.