The film is produced by Ngo Thanh Van and Irene Trinh, based on the script written by Leon Le and Nguyen Thi Minh Ngoc.
Throughout the film, cai luong music is highlighted and plays a leading role in the entire story line.
The film's title itself is also named after a musical instrument that plays the role of keeping the beat in cai luong.
However, because the original idea was not feasible, after a few years he sought out writer Nguyen Thi Minh Ngoc to rewrite a more suitable script.
The filming process took place over 32 non-consecutive days, with scenes mainly taken in District 5 of Ho Chi Minh City.
Dung's parents used to follow a cai luong theater troupe, but his mother – Hong Dieu – could not stand the situation so she left the family when he was young.
Linh Phung was very impressed with Dung's skills and advised him to return to cai luong, which was his family's tradition.
Many viewers, after watching the film, asked themselves questions about the relationship between the two characters Dung and Linh Phung: Is it love, or is it simply the sympathy, connection, and compassion in a moment of two strange souls who are extremely lonely?
Writer Quang Duc of Zing News compares this relationship to the chemistry between the two main characters in the Korean film The King and the Clown, "a kind of brotherly love, in sympathy, that cannot be named", in which "Isaac's eyes and appearance as Linh Phung are similar to those of Lee Joon-gi as Lee Gong-gil, a very feminine look.
While Lien Binh Phat and Dung Thien Loi as Kam Woo-sung as Jang-saeng, also dusty and careless."
This writer also commented on the love scene between Dung and Lan that completely "did not reveal a bit of male or female skin, [...] the director must have had an intention.
Ngo wanted the two main characters Dũng and Linh Phụng to have more on screen physical contact, but Le firmly refused.
[7] When asked about his choice of actors, Le stated that he saw Phung's "fragility and loneliness" in Isaac whereas newcomer Liên Bỉnh Phát has the appearance and soul of Dung.
[9] Online publication New Mandala praised Song Lang for "its honest portrait of Saigon as a city in the middle of cultural, social and political transitions" and "microscopic attention to objects that were used in the everyday lives of Saigonese at that time"[10] and The Hollywood Reporter called it "a uniquely Vietnamese hybrid of Wong Kar-wai's In the Mood for Love and Richard Linklater's Before Sunrise".