“So” means to sing in response to other’s singer’ song. These folk songs are native to the eight northern provinces of Thailand, including some areas of Sukhothai, Uttaradit and Tak provinces.So singing has duet parts in the manner of courtship ritual dialogue, or solo part to narrate a story or describe anecdotes or happenings, accompanied by folk music.
So singers are called chang so in vernacular dialect. The male and female singers who respond to each other in the duet are called khu thong. They must be well-trained, skilled, and have a quick wit for improvisation so that they can promptly and spontaneously respond to the other singer. They must be knowledgeable and have a good memory so that they can use their general knowledge in their singing. They must also memorise all the standard tunes by heart.
The lyrics for the so singing are improvised, depending on the circumstance and occasion. For example, if it is an ordination ceremony, the chang so will sing about filial piety.
So songs and tunes are divided according to the cultural geography into two sub-regions:
- West Lanna sub-region, which comprises Chiang Mai, Chiang Rai, Lampang, and Lamphun provinces. So singing in this sub-region is called “So Chiang Mai” and is accompanied by a pi or a Wong Pi Chum (a pi chum band). A pi chum is a single-reed woodwind instrument made of bamboo, with a metal reed. The music from the reed instrument is the principal accompaniment. So Chiang Mai has seven principal standard tunes: Tang Chiang Mai, Chapu, Lamai, Ngiao, Phama, Ue, and Phra Lo or Long Nan;
- East Lanna sub-region, which includes Nan, Phrae, some parts of Chiang Rai, and Phayao provinces. So singing from this sub-region is called “So Nan” and is accompanied by a salo and a pin (sueng). So Nan’s standard tunes are: So Long Nan, Lap Laeng, Dat Phrae, and Pan Fai.
So Chiang Mai is generally faster than So Nan in tempo. So singing performance begins with the rite of Paying Homage to the Teachers, followed by a Hom Rong (Overture), a Kroen (Introduction) before entering the main section, and ends with a Phleng La (Farewell song).
So singing has evolved through the ages. For example, during King Rama V’s reign, Queen Consort Chao Dara Ratsami initiated Lakhon So (So Dance Drama) in Chiang Mai Province; and in 1965, So String, a contemporary orchestra, was created to play the adaptations of some so tunes in Western-style orchestration.
So has a long history. It is an important and prominent cultural identity of the Lanna people and is associated with the lifestyle of the Lanna people in various ways–with their beliefs, values, tradition and customs, religious life, family, profession and livelihood, food and clothes. In addition to that, the lyrical beauty of the verses in vernacular dialect or Kham Mueang reflects the intellectual heritage that was developed and refined through generations of their ancestors -- a gift to be cherished and passed on to the future generations.
Regrettably, today so singing does not receive as much interest as it should be because of the popularity of modern music and TV soap operas. It is fading into oblivion -- a similar fate that awaits the other traditional folk singing and songs in Thailand.
Prominent so Lanna singers are: National Artist Mae Khru Chansom Saithara, National Artist Pho Khru Khamphai Nuping, Mae Khru Buason Thanombun etc.