Ca trù (歌籌) "song with clappers," also known as hát ả đào or hát nói, is an ancient genre of chamber music featuring female vocalists, with origins in northern Vietnam. For much of its history, it was associated with a geisha-like form of entertainment, which combined entertaining wealthy people as well as performing religious songs for the royal court.
There are different myths and theories related to ca trù's conception. One story states that a woman named Ả Đào created the genre, having charmed the enemy with her voice (thus explaining one of the genre's alternate names: Hát ả Đào). Another theory points to a woman named Đào Thị, a talented musician who was beloved by the Lý Dynasty imperial court. This theory also claims that ever since the time of Đào Thị, in admiration of her, women who held a profession as singers (such as ca trù singers) were referred to as Đào nương ("nương" here refers roughly to "maiden" or "lady"). The latter is true although this term is no longer widely used in modern Vietnam.
What is known for sure is that ca trù started off like many of Vietnam's arts as being a form of entertainment for the royal court. Officially ca tru count the age of their profession since The Later Ly dynasty (Vietnamese: Nhà Hậu Lý, 1010—1225), at that time musicians called Vietnamese: hát khuôn performed only on religious court ceremonies. It was only later on that it branched out into being performed at small inns. Indeed, it was mainly scholars and other members of the elite who enjoyed the genre, which was somewhat inaccessible to the masses (who enjoyed the Hát chèo opera genre much more).
In the 15th century ca tru spread through Northern Vietnam. The artists might be called to celebrate a son's birth, or to celebrate the signing of a contract. Ca tru were outside of the caste system, so they could entertain the most noble clients.
In the 20th century, ca trù nearly died out. When the Communists came to power after the 1945 August Revolution, ca trù was systematically suppressed, becoming associated with prostitution and the degradation of women. Consequently, before 1976 there existed only two ca tru: Vietnamese: Nguyễn Xuân Khoát and Vietnamese: Quách Thị Hồ. Later they both started to revive the tradition of ca tru. In actuality, men were allowed many wives in the past and having extramarital affairs was nothing shocking. Thus, it was commonly known that many famous ca trù singers did indeed have affairs with important men, but it was just something to be accepted as a part of society back then, and not a part of the profession itself.
As of 2009, extensive efforts are being made to invigorate the genre, including many festivals and events where several types of ca trù (among other related arts) are performed. Vietnam has also completed documents to have ca trù recognized by UNESCO as an Intangible Cultural Heritage.
By 2011 there were 140 ca tru from 23 clubs.
Ca trù, like many ancient and highly developed arts, has many forms. However, the most widely known and widely performed type of ca trù involves only three performers: the female vocalist, lute player and a spectator (who also takes part in the performance). Sometimes dance is also performed at the same time.
Last is the spectator (often a scholar or connoisseur of the art) who strikes a trống chầu (praise drum) in praise (or disapproval) of the singer's performance, usually with every passage of the song. The way in which he strikes the drum shows whether he likes or dislikes the performance, but he always does it according to the beat provided by the vocalists' phách percussion.
New observers to the art often comment on how strikingly odd the vocal technique sounds, but it is the vocals themselves that are essential in defining ca trù.
Ca trù inns 
Ca trù literally translates as "tally card songs." This refers to the bamboo cards men bought when they visited ca trù inns, where this music was most often performed in the past. Men would give the bamboo cards they purchased to the woman of choice after her performance, and she would collect money based upon how many cards she was given.
Scholar-bureaucrats and other members of the elite most enjoyed this genre. They often visited these inns to be entertained by the talented young women, who did not only sing, but with their knowledge of poetry and the arts could strike up a witty conversation along with serving food and drink.
Besides these inns, ca trù was also commonly performed in communal houses or private homes.
Ca trù in modern Vietnamese media 
Along with efforts made to preserve the genre, ca trù has been appearing in much of recent Vietnamese pop culture, including movies such as the award-winning film Mê thảo: thời vắng bóng, or its mention during popular entertainment shows such as Paris by Night. It has even been used in Vietnamese pop music, where many artists have attempted to successfully synthesize ca trù (or aspects of it) with pop or other modern genres.
Bich Cau Dao Quan Club, founded in 1992, now has 90 members, 30 or 40 of whom gather on a given Saturday evenings. The oldest artist is 88 years old. According to the director, 50-year-old Bach Van, who trains younger singers and introduces them to classical songs: "It is very difficult to find young singers who wish to learn this art form. It is also difficult to find good teachers who can convey both the enthusiasm and the technical knowledge." Bach herself studied ca trù for ten years before the Hanoi Office of Culture appointed her the club's director. Bach is not in good shape since August 2007, contact Ca Tru fans
Notable performers 
Notable contemporary ca trù performers include
- Ca tru Thang Long: Nguyễn Thị Chúc (voice; b. 1930), Nguyễn Phú Đẹ (đàn đáy, b. 1923), Phạm Thị Huệ (the first female ca trù singer in Vietnam who learned to play the đàn đáy) and her daughter Nguyễn Huệ Phương (voice, b. 1999), her students Nguyễn Thu Thủy (đàn đáy, b. 1986) and Nguyễn Thùy Chi (voice, b. 1992)
- Ca tru Thai Ha: Nguyễn Văn Mùi (the director , based in Hanoi; drum) and his daughters Nguyễn Thúy Hòa (voice; b. 1974), Nguyễn Thị Hà Vy (voice), and his sons Nguyễn Mạnh Tiến (đàn đáy; b. 1970) and Nguyễn Manh Khuê (đàn đáy; b. 1962). Nguyễn Văn Mùi's granddaughters, Nguyễn Kieu Anh and Nguyễn Thu Thao (both b. 1994) are also ca trù vocalists. Nguyễn Thúy Hòa was taught by Ms. Quach Thi Ho, a renowned performer who began recording in 1955.
- Norton, Barley. "Singing the Past: Vietnamese Ca Tru, Memory, and Mode." Asian Music, vol. 36, no. 2 (Summer/Fall 2005).
- Mê Thảo, Thời Vang Bóng. Directed by Việt Linh.
See also 
- Music of Vietnam
- Vietnamese theatre
- Traditional Vietnamese dance
- Culture of Vietnam
- History of Vietnam
- Norton, Barley. Ca Trù: A Vietnamese Chamber Music Genre. International Association for Research in Vietnamese Music.
- "Ca trù singing", UNESCO.org.
- CHANTER LE CA TRÙ AU VILLAGE DE LÕ KHÊ (NORD DU VIET-NAM) Une fête rituelle au temple communal et à la maison des patrons de métier du ca trù A ANISENSEL - Péninsule, 2009 - cat.inist.fr Résumé/Abstract L'article porte sur la tradition musicale du ca trù (chant à tablettes) telle qu'elle s' est perpétuée dans un village aux portes de Hanoï, le village de Lô Khê. Le ca trù y revêt une fonction rituelle inscrite au coeur même de la tablette «trù» par laquelle les ...
- "Bao HA NOI MOI dien tu", HanoiMoi.com. (Vietnamese)
- "Ca tru", CaTruThangLong.com.[dead link]
- Возвращение музыкального кружка. (Russian)
- "The Exotic Sounds of Ca Tru", ThingsAsian.com.
- "Quach Thi Ho — The woman faithful to Ca tru", CaTruThangLong.com.[dead link]
- "National fest honours art of ca tru singing", VietnamNews.VNAgency.com.vn.
- "Ca tru — Vietnamese cultural heritage", CaTruThangLong.com.[dead link]
- Terry E. Miller, Sean Williams (2008). The Garland handbook of Southeast Asian music, p.262. ISBN 9780415960755. "This lute is the only stringed instrument used to accompany ca trù singing."
- Ca tru Thang Long club
- Ca tru page from Roehampton University site
- Ca tru tradition
- Article about Barley Norton and ca tru (Vietnamese)
- Ca Tru Singing