The "sabbatical" and "extended-sabbatical" of the Covid pandemic has proved to be a boon for me, especially in revisiting my hobbies, interests and diving deeper into the theoretical aspects of music.
Here in this post, I try to find some commonalities and differences in different styles of classical music, namely Western classical , Jazz, Hindustani Khayal , Dhrupad and Carnatic
The Anatomy and Physiology of "Hearing"
The human ear has the ability to sense sound waves with frequencies from 20 Hertz to 20000 Hertz. The cochlea is a hollow, spiral-shaped bone found in the inner ear that plays a key role in the sense of hearing and participates in the process of auditory transduction. Sound waves are transduced into electrical impulses that the brain can interpret as individual frequencies of sound. The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modulus. (Wiki )
The idea behind appreciating certain frequencies and group of frequencies of sound as "musical" stems from this peculiar anatomical and physiological configuration in humans.
Here is a crisp video on Youtube that explains the process of sense of hearing.
Detailed video of Anatomy and physiology of hearing could be seen here on Youtube
Music - Octave , Saptak , Scale
Octave, in western music, an interval whose higher note has a sound-wave frequency of vibration twice that of its lower note. Thus the international standard pitch A above middle C vibrates at 440 hertz (cycles per second); the octave above this A vibrates at 880 hertz, while the octave below it vibrates at 220 hertz.
The same concept in Hindustani, Dhrupad and Carnatic music is called a "Saptak"- set of seven major notes named Sa-Shadaj, Re-Rishabh, Ga-Gandhaar, Ma-Madhyam, Pa-Pancham ,Dha- Dhaivat ,Ni- Nishad
The western system has 8 distinct frequencies (points) while the Indian system accounts for the 7 unique spaces(lengths) between two sound frequencies, the 8th with twice the frequency of 1st. This is the basic difference between the approach and the conventions of Indian and the Western system.. hence Octave(8) Vs Saptak (7)
The space (length) between 1st and 8th note is divided equally in Western System (Equi-tempered). Each note including the base note (Do to Ti) could be lowered (flattened) or raised (sharpened).
In Indian system the space (length) between 1st and 8th note is initially divided in two parts by a stable 5th note (Pancham, Pa), that is also called Achal swar- The note that doesn't move, cannot be lowered or raised. Same is the case with base note or Shadaj-Sa, that cannot be lowered or raised. Hence these two notes (1st and 5th) are called Achal swars or fixed swars (notes)
Essentially , Western system defines frequencies of notes and have labelled them A to G. Arithmetic equi-tempered division between any two notes, higher note being double the frequency of lower note (A = 440 hertz , higher A = 880 hertz) . A to G progressing in Arithmetic fashion. Also, there is a note placed between two consecutive note at the halfway distance, called semi-tone, half note higher than the lower note (sharpened) and half note lower than the higher (flattened)
While the Indian system defines the space between the consecutive notes in a scale and gives a range of frequencies for the note in that space. The progression of notes from a Shadaj- Sa (base) to the next Shadaj- Sa (higher scale) has a Geometric progression or ratio relationship to next note till it reaches double the frequency (Shadaj of higher scale )
Classification of Scales - Western Modes and Indian Ragang / Thaat system
Music derives its origin from religion. Singing of hymns had a musical base that created various moods. In early writings of both Plato and Aristotle (approx. 350 BC) there are large sections that describe the effect of different musical modes on mood and on character formation.
These modes in Western music (also known as Church modes), could be called for simplicity, as classification of group of notes to form scales. They are now common part of the modern Jazz music. Here is a quote from the "Politics" by Aristotle about how set of notes (modes) have effect on human moods...
“The musical modes differ essentially from one another, and those who hear them are differently affected by each. Some of them make men sad and grave, like the so called Mixolydian; others enfeeble the mind, like the relaxed modes; another, again, produces a moderate or settled temper, which appears to be the peculiar effect of the Dorian; and the Phrygian inspires enthusiasm.”
A similar effect of group of notes sung in certain way ( Raags) have been mentioned in the theories of Dhrupad music and later in Hindustani Khayal music system. The Western system had classified the scales early in form of modes or Church modes , that could be compared to the Ragang system of classification based on the "Bhaav" or mood created by the set of notes. Also the later classification of Hindustani Khayal system into 10 Thaats by Pt Vishnu Digambar Bhatkhande, in 20th century, could be compared to the "Modes" in Western music.
In my opinion , the Thaat system has classified the group of notes into more granular form into 10 thaats as against the 7 modes of the Western system.
There are no equivalents to the thaats Kalyan, Purvi, Todi and Marwa that have Sharp 4th note ( tivra madhyam). Also, the Locrian mode is unique in the sense that it does not have an equivalent in Thaat system as it lacks the 5th note (pancham) and has two 4th notes (madhyam), something observed in Yaman Kalyan and Lalat raag or Lalitang raags.
Thus, the common features and principles of music run through the theories of all classical music based on the human ear anatomy, physiology and psychology that has the influence of culture. The differences that I observe are mainly in the form of stress during performance:
1) Western music is Harmony based, stress is on reproduction of written music without improvisations.
2) Hindustani Khayal and Dhrupad is Melody based with stress on swar / note quality and the improvisations within the frame of the rules of a " Raag" to create a certain kind of mood or "Bhaav" among the audience. The repetitive rhythmic cycles are critical part of these systems. Each improvisation, thought or "Khayal" is typically completed at the "Sam" or first beat of the upcoming rhythmic cycle. This makes the audience a critical part of the performance !
3) Carnatic is rhythm centered with a stress on specific frequency of a swar or note (something close to the Western Classical )
4) Jazz music, which I think has the common qualities from both the Western Mode system and the improvisation of Hindustani Khayal music system.
Will continue to explore more such comparative studies. All suggestions / corrections / opinions are welcome.