Your voice is like a fingerprint made of sound. No one else has the exact mix of tones that you produce. Long before smartphones existed, radio operators could recognise who was speaking just by listening carefully. Today, speech-recognition apps do something similar using maths. They look at patterns hidden inside your voice to figure out what you are saying.

In this activity, you will explore what makes your voice unique by studying the frequencies that appear when you speak different vowels.

Every voice has its own unique sound, just like Amitabh Bachchan’s deep and powerful voice or Taylor Swift’s soft and high one. Just like musical instruments, our voices can produce a range of notes or pitches. In Indian music, these notes are known as Sa, Re, Ga, Ma, Pa, Dha, Ni, Sa′. Great singers like Lata Mangeshkar and Kishore Kumar are known for their wide pitch range, as they could comfortably sing from a low Sa to a much higher Sa′.

In this activity, you’ll explore how pitch changes as you move from Sa to Sa′ and see how the range of frequencies varies between different people. You’ll get to see your voice as sound waves on your phone using a frequency analyzer app like Spectroid.