Santoor

Indian concert santoors are built from walnut, the traditional tonewood of Kashmir. Walnut's moderate density and even grain give the resonating chamber a warm, focused tone across the instrument's three-octave range. The trapezoid body is hollowed from thick planks; its angled sides place the bass bridges on the right and the treble bridges on the left, so each hand reaches its register without crossing. The body depth runs 7–9cm at centre, which determines how long string vibration sustains before decaying.

Twenty-five wooden bridges cross the string field, each standing 3–4cm tall and supporting four strings tuned in unison. The bridges sit on felt pads to prevent the body from deadening their resonance. The strings run from tuning pegs on one side of the body over the bridges to anchor pins on the opposite side. Steel strings serve the treble; brass-wound steel strings carry the bass. String gauge varies from thin treble to heavier bass to keep playing tension consistent across the full range. Tuning pegs are tightened with a dedicated tuning hammer; the instrument goes out of tune with temperature and humidity changes and needs adjustment before each session.

The mallets, called mezrabs, are 25–30cm shafts of walnut or maple with curved or padded tips. The tip material shapes tone: bare wood gives a brighter, more percussive attack; cloth-padded tips give a softer sound suited to alap. Mezrabs sit between the index and middle fingers with a loose grip; the wrist delivers a bouncing stroke, and pressing into the string kills tone. Makers balance tip weight against shaft stiffness to give each mallet the right response speed for the register it covers.