What is a mridangam?

The mridangam is a double-sided drum whose body is usually made using a hollowed piece of jackfruit wood about an inch thick.

The two mouths or apertures of the drum are covered with a goat skin leather and laced to each other with leather straps

around the circumference of drum. These straps are put into a state of high tension to stretch out the circular membranes on

either side of the hull, allowing them to resonate when struck. These two membranes are dissimilar in width to allow for the

production of both bass and treble sounds from the same drum.

The bass aperture is known as the "thoppi" or "eda bhaaga" and the smaller aperture is known as the "valanthalai" or "bala

bhaaga". The smaller membrane, when struck, produces higher pitched sounds with a metallic timbre. The wider aperture

produces lower pitched sounds. The goat skin covering the smaller aperture is anointed in the center with a black disk made

of rice flour, ferric oxide powder(rock powder) and starch. This black paste is known as the "sAtham" or "karnai" and gives

the mridangam its distinct metallic timbre. The combination of two inhomogeneous circular membranes allows for the production

of unique and distinct harmonics. Pioneering work on the mathematics of these harmonics was done by Nobel Prize winning

physicist C. V. Raman.

Immediately prior to use in a performance, the leather covering the wider aperture(left side for right handed mridangists) is

made moist and a spot of paste made from rava flour and water is applied to the center, which lowers the pitch of the left

membrane and gives it a very powerful resonating bass sound. The artist tunes the instrument by varying the tension in the

leather straps spanning the hull of the instrument. This is achieved by placing the mridangam upright with its larger side

facing down, and then striking the tension-bearing straps located along of circumference of the right membrane with a heavy

object (such as a stone). A wooden peg is sometimes placed between the stone and the mridangam during the tuning procedure to

ensure that the force is exerted at precisely the point where it is needed. Striking the periphery of the right membrane in

the direction toward the hull raises the pitch, while striking the periphery from the opposite side (moving away from the

hull) lowers the pitch. The pitch must be uniform and balanced at all points along the circumference of the valanthalai for

the sound to resonate perfectly. The pitch can be balanced with the aid of a pitch pipe or a tambura. The larger membrane can

also be tuned in a similar manner, though it is not done as frequently. Note that since the leather straps are interwoven

between both the smaller and larger aperture, adjusting the tension on one side often can affect the tension on the other.

The mridangam is played resting it parallel to the floor. A right-handed mridangam artist plays the smaller membrane with his

or her right hand and the larger membrane with the left hand. This can be described in words as follows: The mridangam rests

upon the right foot and ankle, the right leg being slightly extended, while the left leg is bent and rests against the hull

of the drum and against the torso of the artist. For a left-handed percussionist, the legs and hands are switched.

Students of this art are required to learn and vigorously practice both the fingering strokes taught as the training becomes

more advanced, which are generally used as aesthetic embellishments while playing.The combination of these finger strokes

produces complex mathematical patterns.

Today the mridangam is most widely used in Carnatic music performances. These performances take place all over Southern India

and are now popular all over the world. As the principle rhythmic accompaniment (pakkavadyam), the mridangam has a place of

utmost importance, ensuring all of the other artists are keeping their timing in check while providing support to the main

artist. One of the highlights of a modern Carnatic music concert is the percussion solo (thani avarthanam), where the

mridangam artist and other percussionists such as kanjira, morsing, and ghatam vidwans exchange various complex rhythmic

patterns, culminating in a grand finale where the main artists resumes where he or she left off. Mridangam is used as an

accompanying instrument in Yakshagana Himmela (orchestra) where it is called Maddale. However, Mridangam used in Yakshagana

is markedly different in structure and acustics from the ones used in Carnatic music.