Venkatamakhin or Venkateswara was the son of the musician, scholar, and priest, Govinda Dikshita, a Kannada Brahmin from the Mysore area, who was also a minister of Raghunatha Nayak of Thanjavur. He was instructed in the veena by his father and his brother, Yagnanarayan. He was later schooled in the scholarly aspects of classical music by Tanappacharya. Venkatamakhin was also versed in Sanskrit and equipped with knowledge in varied subjects such as astrology, logic, philosophy, and alankara.
Like his father, Venkatamakhin served as a minister to Raghunatha Nayak's successor, Vijayaraghava Nayak (r. 1633–1673). Seeing as to how there was no authoritative treatise on the classification of ragas in Carnatic music, the king commissioned Venkatamakhin to compile the Chaturdandiprakashika, his most renowned work.[1] He was devotee of Tyagesha, the presiding deity of Tiruvarur, and composed 24 ashtapadis in his honour.
Venkatamakhin's Chaturdandi Prakasika was a landmark in the annals of Carnatic music. It had been in circulation only in manuscript form until it was taken up for print early in the 20th century. It gives a systematic and scientific classification of Mela ragas based on swaras. The name itself means ‘Exposition or illumination of the four channels through which a raga manifests itself’. Out of the ten chapters, the last and part of the ninth are said to be missing. Twelve hundred and odd couplets available are in simple, elegant Sanskrit.
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His grandson, Muddu Venkatamakhi, added a supplement to the work.
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Yes, they were. Their compositions and the scale they used for the ragas reflect this. Before I give the explanation lets travel down the History lane a bit. From a theoretical standpoint Carnatic music witnessed a major turning point during the reign of Tulaja Maharaja. This was the time when Carnatic music shifted its epicenter to Tanjore Courts.
Venkatamakhin a scholar at Tanjore court tried to give a formal definition to Janaka and Janya Ragams. Ragams in olden times were categorized as Upanga, Bhasanga, Kriyanga and Raganga Ragams. Venkatamakhin tried to permute the 12 notes and came up with his 18 raga Melakartha scheme. Later he added a 19th raga Desi simhavaram to his list, thus he formulated 19 Melakartha or Janaka ragams. He wrote his treatise in Chaturdandi Prakashika in 17th century.
Later, two other musicologists, Muddu Venkatamakhin (Venkatamakhin's grandson) and Govindacharya delineated the groundwork of Venkatamakhin. Thus two separate streams of scale usage evolved. Muddu followed the asampurna mela structure of his grand father and added 51 more ragams totaling to 72.
Govindacharya followed the Sampurna system and he gave new names to all the 72 melakartha ragas which was later put into 12 chakrams of 6 ragams each.
Thyagaraja followed Govindacharya scheme and Deekshitar followed Muddu Venkatamakhin scheme. Shyama Shastri krithis show influences of Govindacharya scheme. Lets move onto the answer now - what we can learn from their krithis.
1. Deekshitar gave life to all 72 asampurna ragams of Muddu Venkatamakhin. He has excelled in exploring the melodic beauty of Vivadi ragams. His ragamudra is a evidence to that. His compositions in Sumadhyuti, Chamaram, Kanakambari, Rasamanjari etc establish the old raga names.
2. The 22 nd melam is Sri Ragam. Deekshitar has 5 compositions in Sri Ragam, not a single one in Kharaharapriya since the latter doesn't exist. Gowri Manohari in Venkatamakhin scheme allows Suddha Gandharam and Sadharana Gandharam, thus the krithi Kowmari Gowri uses both.
3. Raga names and Scale discrepancies - Deekshitar distinguished ragams like Abheri, Devagandharam, Suddha Saveri, Devakriya, Udayaravichandrika, Suddha Dhanyasi separately. His krithis in each of these are evident. Thus he used the old scale and not the one formulated by Govindacharya. He used Dhaivatham in Nattai and Sree raga which indicate the asampurna mela structure, all 7 notes either in arohana or avorohana. Arabhi uses traces of Nishadam.
4. Deekshitar does not have a single krithi in Reethigowlai. His two compositions on Neelotpalamba are Narireethigowlai and the raga mudra is evident. Same goes for Harikedaragowlai. Another Scalar difference is Hindola Vasantham. His usage of Durbar ragam showed traces of Karnataka Kapi indicative of Ma Ri Ma Ri Sa phrases as opposed to Ga Ga Ri Sa of Durbar.
5. Coming to Thyagaraja compositions, we can see plenty of compositions in Kharaharapriya. His Nattai and Sree Ragam compositions do not have Dhaivatham.
6. The number of Vivadhi raga compositions of Thyagaraja seem to be less compared to Deekshitar. Thyagaraja Abheri and Udayaravichandrika differ from Deekshitar's.
7. In order to comply with Katpayadi Sankhya, the Hari from Harikedaragowla was copied to Kamboji making Harikamboji as 28th me lam in Govindacharya scheme. Thyagaraja weaved out beautiful compositions in Harikamboji.
PS : Since the reason for Deekshitar to follow Muddu Venkatamakhin system was asked - here it goes
Ramaswamy Deekshitar (father of Muthuswamy) a prolific composer himself, for raga lakshanams sought out to Venkatavaidyanatha Deekshitar a descendant of Venkatamakhin for his compositions. Thus Muthuswamy followed his father's way and composed in 72 raganga ragas. The word ragangam was used by Venkatamakhin instead of Mela raga but meaning the same, a parent raga of many ragams.
The last raganga raga in Venkatamakhin scheme is Rasamanjari. Deekshitar 's krithi in it tells us that he had a clear idea on composing in all 72 raganga ragas.
The line in the Rasamanjari krithi - Sringara rasamanjarim - "ananga kusumAdi Sakti priya-karIM dvi-saptati - rAgAnga rAga mOdinIM " establishes the 72 (dvi saptati) ragams here.
901 views · View Upvoters · Answer requested by Vi Jay
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Satheesh has written a beautiful answer.
All were aware of Venkatamakhin's works.
But Tyagaraja mostly followed the later sampurna melakarta scheme of GovindacArya.
Tyagaraja has composed and has given life to many of the sampurna melas, especially
the ones like GanamUrti (gAnamUrte...), Dhenuka ("teLiyalelu rama.."), vakuLAbharaNam ("erAmuni nammitino"), kharaharapriya, nAgAnandini (sataleni..),
and more importantly Charukeshi (instead of Tarangini) and harikAmboji (instead of harikedaragowla)
This does not mean Tyagaraja avoided Asampurna melas. In fact, Tyagaraja did compose in 14th asampurna "Vativasantabhairavi" (famous nI daya rAda..) along with Vakulabharanam, and ragas like "Sri" and "Kiranavali",
and lots more.
Muttuswami Dikshitar, instead, was following only the Muddu Venkitamakhin's asampurna scheme of his period. Muttuswami Dikshitar has given life to all the 72 asampurna melas, that the asampurna scheme is often referred to as of the "Muttuswami Dikshitar" school.
Shyama Shastri, but has not spared us with adequate compositions in sampurna scheme
or asampurna scheme.