“Thrayodasa Lakshanas”–the thirteen characteristics of a Raga–which establish the swaroopa or melodic entity of the raga.
The thirteen characteristics of a Raga are:
Graha Hamsa Mandra Thara Nyasa Apanyasa Sanyasa Vinyasa Bhahutwa Alpatwa Sampoorna Shadava Audava
Graha Swaram
The note on which the Raga is commenced. Starting note of a Sangathi or Item or Ragam. There may be One, Two or even more Graha Swaras in a Ragam.
Hamsa/Jiva Swaram
The note which revealed the melodic entity or the Swaroopa of the Raga (Soul of the raga). To show the Swaroopa of the Raga in an Alapana or sangathi, this note is sung repeatedly, very often. This can be considered as the main swara of the raga. There can be one or more hamsa swaras in a raga.
Graha, Hamsa, Nyasa Swaras are mandatory for the raga. If not specified Shadjam assumes the role of these three.
Mandram and Tharam
The lowest and highest notes respectively, beyond which the raga sancharas should not extend. Mandram defines the notes that are singable in the Mandra Stayi for the particular Raga. The swaras lower than that should not be sung/performed. Similarly, Thara Swaram defines the notes in Thara Stayi which are allowed in the raga.
Nyasa Swaram
Ending note of the raga; the note on which the Raga was concluded.
Apanyasam
A Raga Alapana is done in different sections or parts or stages. Apanyasam is the starting note of each section.
Sanyasam
The ending note of each section in the raga alapana.
Vinyasam
In each section of the Raga alapana, Vinyasa is the note used to show the raga kaLa/chhaya or the essense of raga.
Bahuthwam
The note that is used frequenty in the raga. It has two sub types: Alanganam and Abhyasam.Sancharas revolve around these note.
Alpathvam
The note that is used sparingly in the raga. Two subtypes: Langanam and Anabhyasam. Langanam: The swara is pronounced, but the note sung is actually the neighbouring tone. So though the Langana Swara appears to be performed, the actual shruti/frequency of that swara is rarely performed. It’s like creating an illusion of that swara being sung, while the actual swara sounded is different. Anabhyasam: A note that’s completely omitted or rarely performed.
Sampoornam
A raga consisting of all 7 Swaras in both arohanam and avarohanam is called a Sampoorna Raga. All the sapta swaras are used when performing this raga.
Shadavam
A Raga constituted of 6 notes.
Audavam
A Raga constituted of 5 notes.
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