Shruti box

The shruti box is a member of the free reeds and interruptive aerophones (Hornbostel–Sachs 412.132). Learn how it makes its sound and explore related instruments.

How the shruti box makes its sound

In the Hornbostel–Sachs system, which classifies instruments by how they produce sound, the shruti box belongs to the free reeds and interruptive aerophones: air is periodically interrupted by a vibrating reed or blade – the accordion, harmonica, sheng and bullroarer.

More broadly it is one of the aerophones (wind instruments), where sound comes from vibrating air.

Its timbre – the colour that lets you tell it apart from other instruments playing the same note – comes from the mix of overtones its body and resonator emphasise.

From Wikipedia

A shruti box (sruti box, shrutibox, srutibox or surpeti) is a musical instrument, originating from the Indian subcontinent, that traditionally works on a system of bellows. It is similar to a harmonium and is used to provide a drone in a practice session or concert of Indian classical music. It is used as an accompaniment to other instruments and notably the flute. The shruti box is also used in classical singing. In classical singing, the shruti box is used to help tune the voice. The use of the shruti box has widened with the cross-cultural influences of world music and new-age music to provide a drone for many other instruments as well as vocalists and mantra singing.

Adjustable buttons allow tuning. Nowadays, electronic shruti boxes are commonly used, which are called shruthi pettige in Kannada, shruti petti in Tamil, Malayalam, and Telugu, and sur peti in Hindi.