Chau Van- Vietnam: The Vietnamese are very religious but not fanatical. Compared to other categories, cult music was not widely developed. The most significant cult song type is Hát Chầu Văn. This is a kind of incantation music (although it was classified as ritual music), but its purpose was to hypnotize the person who was estranged from the spirits through musical airs, rythms and lyrics.

Hát Chầu Văn combines trance singing and dancing, a religious form of art used for extolling the merits of beneficent deities or deified national heroes. Its music and poetry are mingled with a variety of rhythms, pauses, tempos, stresses and pitches.

It is in essence a cantillation where the tunes and rhythm depend on the contents of the sung text and may be linked together into a suite, used in relation to a mythical happening, with hints at some features of modern life.

The breathing of a hat van singer comes from his or her midriff to nasal cavity, which works as a resonance box and creates an effect appropriate for religious subjects, particularly when heard in an atmosphere of incense and candles.

The words of the chanting must be clear enough so that all those attending the ceremony are able to understand. There are two kinds of hat van: hat tho and hat len dong.

Hát thờ (worship singing) is the chanting accompanying an act of worship. Hát thờ is slow, grave, and dignified. Variations in the music are few and contain little contrasting pitch and stress.

Hát Lên Ðồng is the cantillation accompanying psychic dancing claiming to respond to occult powers and expressing the will and orders of some super-natural being. It may contain many variations depending on the number of verses sung, often coming to a climax or slowing down to the tempo of a meditation.

The instrumental music accompanying hat van plays a very important role, either in emphasizing important passages or creating contrasting effects, in any event enriching the content of the chant.

The main instrument used in hat van performance is the dan nguyet or moon-shaped lute, accompanied by the striking of the phách (a piece of wood or bamboo) marking the rhythm, xeng (clappers), trong chau (drum) and chieng (gong). The 16-stringed zither (dan tranh) and flute (sao) are also used in the recitation of certain poetry and sometimes the eight-sound band (dan bat am) is also used in certain ceremonies.

Hát Chầu Văn has acquired over centuries both learned and folksy characteristics and has proven to be a strong attraction to musicologists at home and abroad.

The dress worn by hat van singers, based on the cult of the "four palaces", includes a red robe for the cult of the "heavenly palace", a yellow robe for the "underground palace", a green robe for the "musical palace" and a white robe for the “aquatic palace". The style of the robe and the headgear is related to the rank of the supernatural being honoured in the act of worship. Over time, the style of the costume may vary but the rules about the colours have remained unchanged.

The art of hat van originated in the Red River Delta and dates back to the 16th century, later spreading to the whole country. It has also adopted the essential beauty of folk songs from the uplands and highlands of the North, Center and South.

Hát Chầu Văn in North Vietnam

In the North, a ceremony always began with a mass to invite deities to come. The master of the ceremony (cung văn) read a petition and said some incantations to the underworld. After the invitation to the spirits, the person, frequently a woman, who was going to be become the speaker for the spirits sat on a mat in front of the altar. When the spirit had not yet seized the person, the cung văn and the orchestra played together to encourage the spirit to distrain the person.

The lyrics in Hát Chầu Văn were strongly emphasized. The cung văn not only had a good voice and knew how to play musical instruments, but he also knew how to give compliments at the right time and in the proper situation.

Finally the distrained person let the cung văn know by a certain gesture that she had already been seized. When a distrained person was seized, a fairylike life began: a life full of flowers and butterflies like those of te spirits. However, sometimes when te spirits were in a sad mood, the songs and melodies also changed to fit the situation.

Hát Chầu Văn in Central Vietnam

One significant aspect of Hát Chầu Văn in Central Vietnam is that people serve as distrained persons en masse, sometimes five persons participated in the same ceremony.

Every year, a festival of distrained people was organized in the Hòn Chén Palace near Huế. This palace is located on the bank of the Hương River, and because of the outsize number of participants, they had to celebrate the ceremony on their boats. The river was crowded with thousands of boats, thousands of people dressed in colorful clothes, dancing to the offering music in an atmosphere full of incense and scent of offering fruits and flowers. Hát Chầu Văn adopted even the tunes of the Music of the Court Banquet.

Hát Chầu Văn in Central Vietnam is generally more prosperous than Hát Chầu Văn in the North. The melodies lie in many different pentatonics, the rythm is far more complicated than that of the North.

Hát Chầu Văn in South Vietnam

Hát Chầu Văn, also called Hát Bóng, in the South follows the same pattern of Hát Chầu Văn in the North and Center. Some of the tunes are influenced by the classical music of the South.