Melody Instruments
India's long musical history has many references to melodic instruments (for example, Bharata's demonstration of the twenty-two śrutis on two vīnās). The majority of these are stringed musical instruments. In northern India, the most important stringed instruments are the sitār, sarod, bīn, and sarangi. The following descriptions should be treated as general since there are numerous manifestations of each.
The sitār is a plucked, long-necked lute which has its origins in the Persian setar ("three-strings") and popularly ascribed to Amir Khusraw, a musician who lived around the beginning or the 14th century. However, the instrument bears only distant resemblance to the Persian instrument. First of all, the base of the instrument today is constructed from a large gourd (the setar is made entirely of wood). The hollow neck (commonly over three-feet long) is usually made from teak.
The wire "strings" of the instrument are in three functional groups: melody, drone, and resonance. The melody and drone strings - plucked with a wire mizrāb - lie above the fret board and rest on a raised bridge. Only one string is for melody. The principal drone string serves as a secondary melody string. One or more additional strings may provide a drone at a lower pitch and musicians often use them to extend the melodic range of their instrument. At least three high-pitched strings function solely as drone strings. Finally, a number of strings lie below the raised and arched metal frets and rest on a bridge immediately in front of and below the level of the melody-drone bridge. The sole purpose of these strings is to vibrate sympathetically with the pitches played on the melody string.
The sarod is also a plucked lute whose origins are in the central Asian rabāb. Like the sitār, the sarod's strings are functionally differentiated according to whether they are for melody, drone, or resonance (see above). It has four or five melody strings, three to five drone strings, and eleven to sixteen sympathetic strings. Perhaps the most striking aspects of this instrument are the stainless-steel covered, broad, fretless neck face and the skin-covered base. Artisans hew the instrument out of a single piece of wood, usually a little over three-feet long. Musicians play it with a small triangular piece coconut shell. Often a small round brass resonating bowl is attached behind the nut (the point where the neck ends and the upper peg box begins).
The bīn (or rūdra-vīnā) is a "stick-zither," meaning that the body of the instrument is a long tube or stick (in this case around three inches in diameter). The bīn is fretted, has large gourd resonators below the bridge and the nut, and has four, wire melody and three, high-pitched, wire drone strings.
The sārangī is a lute with three or four bowed gut strings which pass over a flat, unfretted neck and a waisted belly covered by a stretched skin where the bridge is supported by a leather band.
This instrument also features up to forty wire sympathetic strings prompting some individuals to derive its name from sao-rangi (instrument of one hundred colors). Although the sarangi is sometimes used as a solo instrument, more often it accompanies the voice.

Above: Ram Narayan
The shahnā'ī is a keyless double-reed aerophone traditionally associated with royal courts. However, the sound of the shahnā'ī is highly desirable at weddings where its loud sound proclaims the event broadly. The best-known shahnā'ī artist of the twentieth century was Ustad Bismillah Khan (b. 1917) whose control of the instrument's sound allowed him to bring it into the context of the concert hall.
Loaded with iconographic significance, the bānsurī (or bānsrī) has associations with shepherds and the god, Krishna. Modern performers such as Hariprasad Chaurasia and G. S. Sacdev draw upon an eclectic repertoire, incorporating material from folk and classical, as well as vocal and instrumental genres. The instrument is a simple bamboo tube with carefully placed finger holes. Bānsurīs come in a variety of sizes (click on the photo to the right to see some examples).
Non-melodic pitched Instruments
The surmandal is a board zither with twenty or more strings, each tuned to a note of the raga under performance. Performers will pluck the notes they are singing, both to confirm the intonation and to echo the pitch. The instrument is hollow, with the back bearing most of the string load. At one end are tuning pegs that performers tune with a tuning "hammer" (wrench). At the other end of each string is a tuning bead that adjusts the pitch by small amounts to correct for strings going out of tune during a performance.
The tambūrā is the most common drone instrument in Indian classical music. The construction of most these instruments (such as the two on the right) is essentially that of a sitār. The base is a dried and hollowed gourd with a wood face. The hollow Teak neck is also in two pieces and fits onto a collar that in turn fits into the gourd. Unlike the sitār, the tambūrā has no frets. The most common versions have four or five strings, wooden pegs above the nut, and tuning beads below the bridges. Tambūrās come in a wide variety of sizes. Tambūrās for vocal performances tend to be larger (four to five feet long), while tambūrās for instrumental performances are usually much smaller (about three feet long). They also often have solid wooden resonator bowls rather than gourds. Both have a bridge with a very slight curvature that allows strings to buzz.
The playing technique emphasizes the sustain of the tambūrā, rather than the articulation. That is, a tambūrā player lets their finger slide off the string rather than a sharp pluck.

Hindustani Sangit Outline Pitch, Scale, Melody
  23-Mar-2017