Image: Mr. Theklan / flickr (CC BY-SA 2.0)
TL;DR: Ca tru, also called hat a dao or hat ca quan, is a traditional Vietnamese chamber singing form in which a dao nuong sings and strikes the phach, a kep dan accompanies on the dan day, and a quan vien cam chau beats the trong chau to praise or fault each phrase. The art nearly vanished in the 20th century, was inscribed by UNESCO in 2009 on the List of Intangible Cultural Heritage in Need of Urgent Safeguarding, and remains on that urgent list because of a lack of performance space, few learners, and difficulty earning a living.
What is ca tru, and which name is correct?
Ca tru is a traditional Vietnamese chamber singing form, performed in a small space with three main parts: a dao nuong who sings and strikes the phach (wooden clappers), a kep dan who accompanies on the dan day (a long-necked lute), and a quan vien cam chau who beats the trong chau (drum) to praise or fault each phrase. It is not a stage form with a large audience. It is an artistic game with its own rules, where listeners sit close and take part directly in each sung phrase.
The name of this form is quite varied. According to an article in Bao Tin Tuc, Đông Môn village (Hòa Bình ward, Hải Phòng) is regarded as the cradle of ca tru in the northern region, and there people also call it hat a dao, hat ca quan. The term ca tru later became the official name, but hat a dao remains common in folk usage and in research works.
One point should be made clear: researchers and practitioners do not fully agree on the origins and some technical details of ca tru. This article follows the currently common convention and notes where opinions differ, rather than presenting it as if there were only one way of understanding it.
How does a ca tru performance unfold?
A traditional ca tru performance usually has three main roles, each with a different function. The dao nuong is the main singer, who both sings and strikes the phach to keep her own rhythm. The kep dan plays the dan day, accompanying and supporting the voice. The quan vien cam chau sits below, holding a drumstick to beat the trong chau, where each drumbeat is a word of praise or criticism for the dao nuong.
The rules of the game lie in the trong chau. The quan vien beats the trong chau not to keep time for the song but to comment. The way of striking, the number of beats, and the position of the beat all carry meaning. This is what makes ca tru different from many other traditional music forms: the audience does not sit still and listen but takes part with its own instrument and with the power to reward or fault.
According to an article in Bao Nhân Dân, at the ca tru class at Bích Câu Đạo Quán (Hanoi), artisan Nguyễn Thị Vân Mai teaches singing technique, while artisan Trần Văn Trúc instructs on playing the trong chau and the dan day. Separating these two parts of teaching shows that the trong chau and the dan day are two independent skills, not simple accompaniment.
Why are they called "nay hot" and "em hoi"?
In ca tru technique there are operations with their own names. The article in Bao Nhân Dân mentions that artisan Vân Mai diligently practices "cach em hoi, nha chu, nay hot". These are distinctive vocal techniques that create the resonant yet thick tone of ca tru.
According to an article on VietnamPlus, what attracts international visitors, including opera artists, is "the raw style of singing with the sound of the phach, the dan day and the technique of nay hat of the ca nuong". In other words, what makes ca tru distinctive lies in its vocal technique and in its raw sound material, without amplification.
Dao nuong, kep dan, quan vien cam chau: three roles, three skills
The three roles in ca tru cannot be substituted for one another. The dao nuong needs voice and phach. The kep dan needs strength and nuance on the dan day. The quan vien cam chau needs knowledge of ca tru to beat the drum correctly.
According to an article in Bao Tin Tuc, artisan Tô Văn Tuyên (born 1982) is a descendant of the To family, one of the families famous for ca tru in Đông Môn. In 2002, he and four others, sponsored by an international organization, joined a national training class for young ca tru performers organized by the Ministry of Culture, Sports and Tourism at the Hanoi Academy of Music. Of the five learners, only Tuyen was male, so he was chosen to play the dan day.
The article quotes Tuyen as saying that the dan day is one of the three instruments used for ca tru and is the heaviest instrument, requiring strength to hold and play. To get a good sound, the plucking hand and the pressing hand must combine harmoniously. This is a fairly specific technical description, showing that the kep dan does not merely accompany but also creates a part with its own expressiveness.
| Role | Instrument | Function |
|---|---|---|
| Dao nuong | Phach | Main singer, keeps her own rhythm |
| Kep dan | Dan day | Accompanies and supports the voice |
| Quan vien cam chau | Trong chau | Comments, rewards or faults each phrase |
Why did ca tru almost disappear?
Ca tru once flourished with the participation of many cultural figures such as Nguyễn Công Trứ, Cao Bá Quát, Tản Đà, Dương Khuê. This information is given by artisan Trần Koóng in an article on VietnamPlus. This shows that ca tru was once a literary and musical activity with an intellectual class taking part, not merely folk entertainment.
According to the article on VietnamPlus, due to changes in a certain historical period, this art form almost vanished from daily life. Artisan Trần Koóng also says that ca tru is still on the list of heritage in need of urgent safeguarding because of a lack of performance space, few learners, and difficulty earning a living.
In Đông Môn, according to the article in Bao Tin Tuc, ca tru became a livelihood for many large families in the village around 1840-1850, then gradually declined through many ups and downs. Around early 1993, the local authorities established the Đông Môn Ca Tru Club, with artisan Tô Thị Chè teaching singing and Mr. Tô Văn Nghị as kep dan. The club kept going but faced many difficulties, mainly due to a lack of funding.
Why is it still "urgent safeguarding" today?
In 2009, UNESCO inscribed ca tru on the List of Intangible Cultural Heritage in Need of Urgent Safeguarding. However, according to the article in Bao Nhân Dân, ca tru still faces many challenges. What troubles artisan Vân Mai is that not a few ca tru forms now exist only on paper, while teaching in many places falls into a state of "tam sao that ban".
The article also proposes: quickly record audio and video of the ca tru forms that artisans still hold, to digitize, standardize and archive them, and at the same time have a strategy for teaching and creating more performance space so that artisans can live by the craft.
Ca tru forms and the work of restoring old repertoire
Ca tru is not a single song but includes many different forms. According to the article in Bao Nhân Dân, artisan Nguyễn Thị Vân Mai can perform nearly 40 ca tru forms, a rich "craft capital" that not every ca nuong has. She once successfully restored the Non mai hong hanh form, absent for more than 70 years, in 2009, alongside tunes such as Mua hat bai bong, Mua hat Dồn Đại Thạch.
This figure shows that ca tru has a large treasury of forms, and losing one form is losing part of the heritage. Also according to the article, artisan Vân Mai was attached to cheo and chau van before turning to ca tru. The turning point came in 1990 when she heard People's Artist Quách Thị Hồ sing "Ty ba hanh" on the radio. At that time, very few people studied ca tru, the master artisans were elderly, so many times when she asked to study she only received a shake of the head. She had to find experts and researchers to borrow old recordings and learn on her own from famous ca nuong such as Mrs. Đinh Thị Hảo, Đinh Thị Bản, Chu Thị Năm.
This story shows a reality of ca tru in the second half of the 20th century: the transmission of the craft was narrowed, recordings became one of the main ways to learn, and learners had to piece it together from many scattered sources.
The revival journey: classes, theatres, giao phuong
From the 2000s, many efforts to revive ca tru were carried out. According to the article on VietnamPlus, the free ca tru class at the Bích Câu Đạo Quán Historical and Cultural Relic (Cát Linh street, Hanoi) was opened in 2008 by Distinguished Artisan Nguyễn Thị Vân Mai and Trần Văn Trúc, a year before UNESCO's inscription. The class runs regularly on Saturday afternoons, at first with only a few students who were children of acquaintances, later attracting pupils, students, workers and international visitors.
According to the article in Bao Nhân Dân, this class charges no tuition and sets no age limit. To sustain it long term, the artisan couple uses income from their family business to cover costs. The class now keeps about 25 regular students, including learners from Hưng Yên and Hải Phòng. From this class have come ca nuong and kep dan who made their names, such as ca nuong Bạch Yến, Minh Hằng, Hồng Pha, kep dan Trần Koóng, and quan vien Thanh Hùng.
In 2017, the Bích Câu Ca Tru Giao Phuong established the Bích Câu Ca Tru Theatre with free performances on Saturday evenings. According to the article on VietnamPlus, after a break due to the COVID-19 pandemic, performances were gradually restored. Since the beginning of 2026, the giao phuong has received on average about 10 international groups per month.
In Đông Môn, according to the article in Bao Tin Tuc, from the 2023-2024 school year, Hòa Bình Primary School was the first unit in Thủy Nguyên district (former) to bring ca tru into teaching in the Local Education subject. Teacher and ca nuong Trịnh Thị Hoài Nam serves as head of the school's ca tru club. In November 2025, Hòa Bình ward held the Ca Tru craft ancestor commemoration, with the program "Ca Tru Space Night" recreating the space of singing and night singing sessions of the giao phuong.
Notable figures and events
| Milestone | Event |
|---|---|
| Around 1840-1850 | Ca tru became a livelihood for many large families in Đông Môn village |
| 1990 | Artisan Vân Mai heard Quách Thị Hồ sing "Ty ba hanh" and began following ca tru |
| 1993 | Đông Môn Ca Tru Club established |
| 2002 | Tô Văn Tuyên joined the national training class for young ca tru performers |
| 2005 | Researchers on Đông Môn conducted research to prepare a dossier for UNESCO |
| 2007 | Artisan Vân Mai won a Gold Medal at the National Ca Tru Festival |
| 2008 | Ca tru class opened at Bích Câu Đạo Quán |
| 1/10/2009 | UNESCO inscribed ca tru as Intangible Cultural Heritage in Need of Urgent Safeguarding |
| 2009 | Artisan Vân Mai restored the Non mai hong hanh form |
| 2017 | Bích Câu Ca Tru Theatre established |
| 2023-2024 | Ca tru entered the Local Education subject at Hòa Bình Primary School |
| 11/2025 | Ca Tru craft ancestor commemoration in Hòa Bình ward |
Ca tru today: what difficulties remain?
According to the article on VietnamPlus, although inscribed by UNESCO in 2009, ca tru is still on the list of heritage in need of urgent safeguarding because of a lack of performance space, few learners, and difficulty earning a living. The class at Bích Câu Đạo Quán keeps about 10-20 regular students. Over the years, hundreds of people have studied, of whom about 30 can sing, play or hold the chau drum.
According to the article in Bao Nhân Dân, artisan Vân Mai says that to sing ca tru, besides talent one needs hard training, so not a few people last only a few sessions and give up. This is a practical challenge: ca tru requires a long learning time, while the livelihood output is narrow.
The direction proposed by artisans is fairly consistent: expand free classes, open more performance spaces, and increase promotion and hands-on experience. According to the article in Bao Tin Tuc, Hòa Bình ward also carries out the project "Restoring the form of singing Cua dinh in the relic space of Phu tu - Đền Ca cong", to recreate the most original values of ca tru and link heritage preservation with cultural tourism development.
Where should one start to learn about ca tru?
If you want to hear ca tru live, the addresses mentioned in the articles above include the Bích Câu Ca Tru Theatre at Bích Câu Đạo Quán (Cát Linh street, Hanoi) with free performances on Saturday evenings, and the Đông Môn Ca Tru Club in Hòa Bình ward, Hải Phòng, which has performances and welcomes visitors.
If you want to study, the class at Bích Câu Đạo Quán accepts students with no tuition and no age limit. However, as the artisans have said, this is a subject requiring long hard training, so learners should plan their time in advance.
One note on approach: ca tru is not a loud form of entertainment. It needs a quiet space, with listeners sitting close and paying attention to each phrase. That is also why this form is selective about its audience, and why it struggles to survive if it relies only on the mass performance market.
