I chanced upon this subject and found that none had contributed. I am just giving what I wrote about this raga about 10 years ago in the Raga Appreciation series in the now defunct sangeetham.com. I have also given Sanjay Subramanyam's observations after my writing.
Raaga Appreciation part 24
15th Jan 2002
asAvEri is believed to have come into prevalence in the beginning of the 17th Century. It finds mention in the Anupa Sangita Vilasa of Bhava Bhatta, of the same period. According to Venkatamakhin, asAvEri is a upAnga janya of janatODi, the 8th mELa in the asampUrNa scheme. The ArOhaNa-avarOhaNa that he gives is SR1M1PD1S' S'N2D1PM1G2R1S - viz., its ArOhaNa is auDava with G and N being varjya. AvarOhaNa is krama sampUrNa. He says the raga can be sung at all times.
In common practice, asAvEri has come to be accepted as a auDava-chatus'svara vakra sampUrNa, bhAShAnga janya of the 8th mELa hanumatODi and the aro/ava is: SR1M1PD1S' - S'N2S'PD1M1PM1R2G2R1S
The anya svara R2 is incorporated in the avarOhana. One of the very few raga-s wherein the anya svara functions as a graha svara. Compositions also commence from S, M1 and P, apart from R2. pancama is a strong nyAsa svara. The rAga chAya svaras are G2, D1 and N2. While G2 and N2 of asAvEri are slightly flatter than those of tODi, madhyama is a bit on the sharper side. Sometimes M is also rendered with kampitam as in bhairavi.
The vakratva in the descent is unique to asAvEri, and is mainly responsible for the melodic entity of the raga, especially its rakti character. Glides from S down to P leading to D1, as well as from M1 to R2 leading to a flat G2 are very special to this raga. This flattened gAndhAra accounts for moods like pathos and entreaty, which are generally associated with this melody.
The raga sounds good both in viLamba kAlam and madhyama kAlam. It sounds beautiful with a profusion of 'vaLi' gamakas in the descending phrases like 'PDSR \NS \P, DP' and 'NSPDMP \R2MPDP'. The nokku while rendering 'MR' is also significant. These are the specialities of asAvEri.
Use of catushruti riShabham: There is a school of thought that R2 was not in use initially, but has come to stay due to the influence of the sharpened enunciation of R1, as in the prayOga SRMP. Yet, in phrases such as R2MPD1S, R2MPDMPMR2G2R1S, SR2M1G2R1S, etc. R2 enjoys a right royal usage in asAvEri. Nevertheless, R1 is also employed in prayOgas like SR1MG2,R1S , SR1N2SP,D1S, etc. This lends a kind of native charm to the raga.
It may be mentioned here that the Hindustani asAvari is different from the Carnatic asAvEri, as the former takes only the tIvra variety of riShabh even though the other svaras are the same as that of the latter.
Even though asAvEri is a raga that can be sung at all times, morning time is more appropriate.
Some of the important sancAra-s are:
R2,m \r2M,P, - DPmpdpm\r2G,R1S -SR1MG_,R1S - sr1sr1N.S \P.,D.S, -
R2MPDS'\ PDP- M,P,DS' - PDS'R'1G'_,R'1S' - G'R2G'_,R'1S'R'1NS'
-PDR'1S'NS' \P - \r2mpD,P,- MP \R2,G_R1S - r2,mpmp,mr2,mp,mr2g_,rs
(\ for iRakka jAru; underscore for flattened G; apostrophe for tAra stAyi;
lower case for double speed).
asAvEri is considered to be a very auspicious raga, hence mangaLams have been composed. Being a rakti raga, it is suitable for padams, opera songs, kuRavanji nATakas and also for kathakaLi performances. The kathakaLi singers revel in this raga. Arunachala kavirayar's rAmanATakam has many compositions in asAvEri, SharaNam SharaNam and kaDaikkaNNAl irangi being the more well known songs of this group.
About 10 kritis of Tyagaraja are available. Of them, the simple and beautiful ones like rA rA mA iNTi, dasharatha nandana, mApAla vElasi, janakajA samEta and lEkanA ninnu are being rendered widely. One of his major kritis in this raga is sArivEDalina kAvEri in praise of the river Cauvery. This song brings out not only the bard's poetic genius and the greatness of the river but also presents a vivid picture of asAvEri. In his navagraha kriti, candram bhaja mAnasa, Muttuswamy Dikshitar brings out the beauty of the raga in a wholesome manner. His other kriti in the raga is kumArasvAminam.
asAvEri has not been handled by many. Of other composers, Koteeswara Iyer's 'kaRpagavalli' in praise of Mylapore Karpagambika and Lalgudi Jayaraman's tAna varNam 'jalajAkShA' on Lord Svaminatha are noteworthy.
The rAga used to be a favorite with nAgasvara vidwans of the bygone eras. Many musicians shy away from singing even kritis in asAvEri, leave alone AlApanAs. It would be good if musicians handled asAvEri more often and presented AlApanAs too, besides the kritis in this raga. Of the few who sing kritis in this raga, D.K. Pattammal deserves special mention for her soulful renditions of mApAla velasi and lEkanA ninnu. It is said that Veena Dhanammal used to consider asAvEri as a pollAda rAgam (a tricky raga) and that she said as much to Musiri Subramania Iyer when he wanted to learn candram bhaja mAnasa from her. Old timers have recalled that her rendering of chandram bhaja mAnasa was a treat to listen to and that it would melt even a stone-hearted person
asAvEri was the subject of much controversy during the raga discussions last year(2000) at the Music Academy. The focal point was the use of catushruti riShabha. The opinions were divided. Musicians like SRJ and Vedavalli quoted textual references as well as their own pAThAntarams to show that chatushruti riShabha was only a result of subsequent usage and there was no sanction under lakshana. But musicians such as S.Rajam and B.Rajam Iyer, both of whom have learnt from Ambi Dikshitar maintained that catushruti riShabha was allowed. Modern renditions of asAvEri use catushruti riShabha a lot.
Raga AlApanAs have been very rare in this raga. One sparkling AlApana I remember was by S.Sowmya at the Rani Seethai Hall, many years ago, preceding Tyagaraja's EpanikO. In modern times TVS has sung a lot of rA rama inTi and kalpana svaras. I also remember a cameo tAnam by S.Balachander some years back as part of a rAgamAlika tAnam that he played.
I have not heard anyone attempt an RTP in this raga. But there is a tAna varnam in this raga and it does offer scope for tAnam singing.