Tehai is a musical motivic device in Indian Classical music, in which a motive is played three times (with a space of 0 to 4 or more beats in between each repetition) and the last note of the third repetition falling on the Sum (beat one of the cycle) (regular), just after the Sum (ateet), or just before the Sum (anagat).
This musical device helps to build tension in the music, provide a final cadence to conclude sections or pieces, and are a vehicle for displaying a musician’s skill and creativity. The mathematics to the tehai are particularly beautiful, and can be complicated to calculate.
In tabla compositions and improvisations, tehai phrases often end in the bol Dha (Tin in roopak taal, and Kat in Dhamar taal).
A Chakradar is a type of composition which consists of an entire composition (including a tehai) played three times (with 0 to 4 or more beats space in between). Therefore, it is a tehai within a tehai.
(This post is about tehais that begin on beat one (Sum) of the cycle. For tehais that are shorter, and begin on other beats within the cycle, see my other post about how I practice and compose these in multiple taals: POST #4 2018 — EKTAAL TEHAI PRACTICE.)
I created these tehai sheets with the goal of getting more intimate with tehais and creating a tool that I could more easily use to compose than using the standard tehai equation:
T: Number of beats in Taal (times number of cycles)
L: Phrase Length (number of beats)
DS: Dha (ending bol of each phrase) + Space (number of beats)
All time values have to match, related to the subdivision of the beat. So, if phrase length is determined in a 2-notes-per-beat subdivision (eighth notes in Western music), the Taal and Dha + Space must also be counted in the same (2 notes per beat/eighth notes).
So, my method for developing this tool was
to solve for the phrase length, L:
This is the equation in the spreadsheet. I have columns for each subdivision: quarters (one per beat), eighth notes (2), sixteenth notes (4), and at the bottom triplets (3) and quintuplets (5). Only the cells with whole numbers are useful in practice.
Note that all Taals divisible by 3 (9, 12, 15, 18) only have tehais with 2-beat spaces. I believe this is because of the thrice repeated tehai phrase in a taal divisible by three has fewer possibilities when the tehai starts on beat one of the taal. (Dha + 2 beats = 3 beats).
I also modified the sheet for half-beat taals (e.g., 7.5 beats).
An example of how to use the spreadsheet is:
Find column 5 (with a “1”), row 12 (with a “14”). Where they intersect there is a “4”.
Column 5 is the DS (Dha plus Space) of 1 beat, in Row 12 which is a 14 beat taal, requires a 4-beat long Phrase. “te re ke te Dha” the 4-beat “te re ke te” phrase plus “Dha” + 0 beats space is the one beat Dha + Space (DS), So:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 +(1)
te re ke te DHA,te re ke te DHA, te re ke te DHA
I also created a summary sheet of the most practical and useful of the tehais gleaned from the original sheets to aid in composition and practice, which I titled “Notable Tehais Sheet.”
I hope this tehai compositional tool is useful for others for understanding the possibilities of tehai and composing tehais of your own.