This form of expression involves the whistling of a finely ornamented melody with the tip of the tongue and the front teeth, accompanied simultaneously by a lower, rumbling base tone produced in the throat, which harmonizes with the higher melody. Mongol Khuumii or throat singing involves producing two simultaneous tones with the human voice. It is a difficult skill requiring special ways of breathing. One tone comes out as a whistle-like sound, the result of locked breath in the chest being forced out through the throat in a specific way, while a lower tone sounds as a base. Khuumii is considered musical art, not exactly singing but using one's throat as an instrument.
Depending on the way air is exhaled from the lungs, there are various ways of classifying hoomii, including Bagalzuuryn (laryngeal) khuumii, Tagnainy (palatine) hoomii, Hooloin (guttural) khuumii, Hamryn (nasal) khuumii, and Harhiraa hoomi: under strong-pressure in the throat, air is exhaled while a lower tone is kept as the main sound. Professional khuumi performers are found in only a few areas with certain traditions. The Chandman district of Hovd aimag (province) is one home of khuumii. Tuva, a part of Russia to the north of Mongolia, is also a center of Khuumii.