(Baha song. The sakwa is a wind instrument made from the horns of a buffalo or antelope) 

 
It is believed that when Pilchu Burhi died, her sons buried her in the vicinity of the village. Later a bamboo tree grew there. One of her sons wished to use the tree to craft a musical instrument, the sound from which would resemble a human voice. But as soon as he approached the tree with the intent of cutting it, he heard a voice asking him to make two tirios from the mid section of the tree – one for the joys of the village and the other for its sorrow. The people, as instructed by the voice, should play the respective flute on both occasions. This would enable Pilchu Burhi to be aware of both their happiness and their suffering from the kind of flute they chose to play. Traditionally, the instrument was used only after the following invocation: “I cut you, dried you and turned you so that even the root of the bamboo tree may hear your sound.”

Unlike the Tumdak and Tamak, the Santals generally make their flutes (tirios and murlis) themselves and are traditionally played in pairs. Its construction is very simple and most Santals have a tirio in their homes. The tirio can only be made from  a type of bamboo whose nodes are far apart and which has a thin wall, with a cross section of at least one inch. The length of the tirio varies from two to three feet.

The tirio has seven holes, one blow hole and six finger holes. A suitable length of bamboo is first cut off from just above a node. This is the hollow end of the tirio. The next cut is made a few inches above the next node on the bamboo. This should yield from end to end, at least two feet of the bamboo length thus cut. The length is examined for straightness and a mark scratched on the surface accordingly.

The bamboo is then measured from node to hollow end. The first finger hole will be made at exactly half this distance from the open (hollow end) and this position is marked first.  Similarly, the other five holes are marked, equally spaced and about an inch apart. The blow hole is pierced into the bamboo with a heated spike about two inches below the node.  The remaining six holes are similarly made. The wider the flute, the larger the size of the holes. Usually, the distance between the blow hole and the first finger hole equals the distance between the first and last finger holes.

Once the tirio is ready, and its inside cleaned of any "fluff" with a long, straight twig, water is poured in from the hollow ends to clean it of bamboo particles and dust. Mustard oil is then rubbed on to the surface and a few drops poured in through the holes. The resin-free oil  helps preserve and condition the tirio; it protects the surface and keeps it from getting dry. It also smoothens the inner surface of the tirio.

When it is used in the villages to accompany songs, for general enjoyment or for their rituals, not much importance is given to whether scales match or not. It is up to the experienced performer  to choose the right tirio or for the singer to match his voice to the tirio. 

The tirio has also played an important role in the history of the Santals. During the Santal rebellion of 1855, it stood as a symbol of Santal identity: Santal villagers were asked by their rebel leaders to hang a tirio at the end of their village lanes, in order to distinguish themselves from the diku (non tribal) inhabitants.