Why Hindustani ragas are associated with different hours of the day

Hindustani classical music, one of India’s oldest and most refined art forms, follows a unique and deeply spiritual principle known as the Samay Raga System—the association of specific ragas with particular times of day. This tradition, rooted in centuries of aesthetic and experiential understanding, is not arbitrary; it is based on how sound vibrations interact with human emotions, the body’s natural rhythms, and environmental energies throughout the day.

The science of sound and circadian rhythm

In Hindustani music, a raga is not just a scale or melody—it is a framework for mood and emotion. Each raga is designed to evoke a particular feeling, or rasa, through specific note patterns, ornamentation, and tonal emphasis. The time theory of ragas states that the emotional essence of a raga is most powerful when performed at its designated hour. This enhances the listener's receptivity and deepens the performer’s expression.

Morning ragas, like Bhairav or Todi, often feature soft, meditative notes and flat tones that mirror the serenity of early dawn. These ragas tend to evoke devotion, calm, and introspection, matching the stillness and purity of the early hours when the mind is most receptive to spiritual experiences.

As the day progresses, ragas become more vibrant and dynamic. Afternoon ragas like Sarang or Shuddha Kalyan express brightness and warmth, reflecting the energy of midday. Evening ragas such as Yaman or Bihag introduce a romantic or reflective quality, mirroring the transition into dusk, a time often associated with beauty and emotional sensitivity. Late-night ragas like Darbari Kanada or Malkauns are deep, slow, and heavy, designed to evoke introspection, mystery, or even longing.

This time-specific practice also has physiological relevance. Studies have shown that the human nervous system, hormonal balance, and even heart rate fluctuate with the circadian cycle. By aligning musical expression with these natural rhythms, Hindustani ragas enhance both emotional resonance and psychological impact.

Thus, the time theory in Hindustani music is not just tradition—it is a sophisticated interplay of art, nature, and human consciousness, offering a unique pathway to emotional and spiritual attunement through the day.