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Exploring the Indian Musical Scale: Sa to Ni and Frequency Adjustments
Exploring the Indian Musical Scale: Sa to Ni and Frequency Adjustments
Understanding the intricacies of the Indian musical scale is a fascinating journey into the harmonious relationships between notes. This article delves into the difference between the seven saras (notes) that form part of the scale starting from Sa, as well as the importance of frequency adjustments and the various tuning methods used in Indian classical music.
Seven Swaras: Sa to Ni
The Indian musical scale is primarily based on seven saras, which correspond to the notes: Sa, Re, Ga, Ma, Pa, Dha, Ni. Let's explore each of them from the starting note Sa (Tonic), which is represented as the first of the seven notes.
Sa (Tonic): The first note in the scale. Re (Second): The second note in the scale. Ga (Third): The third note in the scale. Ma (Fourth): The fourth note in the scale. Pa (Fifth): The fifth note in the scale. Dha (Sixth): The sixth note in the scale. Ni (Seventh): The seventh note in the scale.Starting from Sa and moving up through the sequence of saras will give you all seven notes in the Indian musical scale:
Sa Re Ga Ma Pa Dha Ni
Just Tuned vs Equitempered Tuning
The accuracy of these notes when tuning is an interesting topic. One method of tuning is known as Just Tuning. In this method, each note's frequency is adjusted by adding the 12th root of 2 to the previous note. However, this method is not always accurate, as it may leave the notes out of perfect position when dividing the entire distance of an octave into 12 parts to create just an 12 notes.
A more commonly used method is the Equitempered Tuning. In this system, the octave is divided into 12 equal parts, but the notes are still not in a perfect position. Here, the frequency can be further adjusted by adding a 12th cent, which would differ for different tonic notes. Thus, it is considered inaccurate.
Indian Classical Music and 22 Shruti
Many scholars prefer to use the 22 Shruti system in Indian classical music. This natural scale uses a different approach to categorize the distances between notes into Purna Shruti, Praman Shruti, and Nyun Shruti. For further reading on this topic, you can visit the 22shruti website.
Perceptible Frequency Differences and Semitones
The frequency of an Sa (Tonic) is determined by its absolute pitch. For example, if your Sa is 880Hz, you can increase the pitch by any number or even fractions. However, the human ear cannot perceive small differences. For instance, 880Hz and 885Hz might sound the same to you.
A semitone in western music is considered the safest perceivable difference. In Indian classical music, all saras correspond to integer multiples of semitones. For example, the difference between Sa and Ri1 (A and A) is one semitone, and the difference between Sa and Ri2 (A and B) is two semitones.
The frequency of the next semitone from any given frequency can be calculated using the formula: f2 f1 * 2^(1/12). For example, if your Sa (A) is 880Hz, then R1 (A) would be approximately 932.33Hz.
The amount by which you raise the frequency affects the notes you get. If you increase the frequency slowly by multiples of 2Hz, you will get more than just the 12 notes. If you increase it by 200, you might miss out on one or two.
Conclusion
The art of tuning and understanding the Indian musical scale is essential for musicians and music enthusiasts. The combination of Just Tuning and Equitempered Tuning, along with the precise use of semitones, helps in creating a harmonious and melodious experience. The 22 Shruti system offers an additional level of precision, making it a valuable tool for professionals in Indian classical music.