In my experience and opinion the art of rubab playing resides mainly in the right hand, in rhythmic variations. The disparity between the sound from the downstroke and the upstroke, inherent in the flexed posture of the wrist, means that small differences in the sequencing of downstrokes and upstrokes produces subtle differences in the microstructure of the rhythms produced. Moreover, introducing strokes on the shortest sympathetic string, which functions as a high drone, permits the creation of a seemingly limitless variety of rhythmic patterns. The shortest sympathetic string, the sim-e barchak, is raised by a protuberance on the bridge, to make it more accessible. This is another innovation in rubab design attributed to Ustad Mohammad Omar.
A repeated right hand pattern on the melody strings is called a shahbaz ('plectrum'), and a pattern that also involves strokes on the high drone is a parand and the technique is called parandkari. In playing naghma-ye kashal these techniques are usually applied in the astai section of the composition.
The most basic shahbaz pattern is VAVA with four strokes to the matra. V = a downstroke on the melody strings, A = an upstroke. It is best to think in terms of four matra sequences. Here are four basic right hand patterns:
This is the basic down-up stroke pattern VAVA VAVA VAVA VAVA
VAVV VAVV VAVV VAVV This is a very important pattern. Note that it involves three downstrokes in a row.VAVV VAVA VAVV VAVA
This is a combination of VAVV and VAVA
VAVV AVAV VAVV AVAV
This is a combination of VAVV and AVAV
The easiest way to approach parandkari is to take the three-stroke Dadra pattern and then add the high drone
VAV VAV VAV VAV….. VAV VAV VAV VAV
Here is a very common pattern with 4 strokes to the matra:
VVAV VAVA VVAV VAVA
In the performance of the astai section of a naghma-ye kashal it is common practice to structure the music in a series of episodes, in each of which there is a progressive increase in the number of strokes on the high drone string and some increase in tempo. An episode often terminates with a seh and a drop back to a slightly slower tempo. These features can be heard in the performance of the naghma-ye kashal in Bairami by my teacher Rahim Khushnawaz, accompanied on tabla by his brother Naim Khushnawaz, recorded in 1974. There are six episodes in the astai, and a palta and an antara interpolated at certain points. The 23 repetitions of the astai and the other interpolated sections are identified verbally and the rhythmic patterns used in each episode are shown in western notation (from Baily 1989).
In 1994 I was able to visit Herat again after 17 years and videoed Rahim playing endless cycles of an astai in Rag Talang with different right hand patterns. Here is an extract from his performance, in which he plays 33 cycles of the composition.
An analysis of Rahim's performance of astai in Rag Talang is shown below. Rahim names certain qualities of some of the patterns in response to my questions. In his descriptions ahesta = a slow and simple version of the astai, rasta = straight-forward, chapa = upside down or back to front, yek la = slow tempo and rizdar = with tremolo.
01. ahesta + seh
03. V-V- │ V-V- │ V-V- │ V-V- (rasta, yek la)
04. V-V- │ V-V- │ V-V- │ V-V-
05. V-V- │ V-V- │ V-V- │ V-V- (chapa)
06. V-V- │ V-V- │ V-V- │ V-V- + seh
08. VAVV │ AVVA │ VAVA │ VAVA (chapa)
09. VAVV │ AVVA │ VAVA │ VAVA
10. VAVV │ AVVA │ VAVA │ VAVA
11. VAVV │ AVVA │ VAVV │ AVVA
12. VAVV │ AVVA │ VAVV │ AVVA + seh
14. VAVV │ AVVA │ VAVV │ AVVA (rasta)
15. VAVV │ AVVA │ VAVV │ AVVA
16. VAVV │ AVVA │ VAVV │ AVVA
18. VAVAV │ VAVAV │ VAVAV │ VAVAV (rasta, rizdar)
19. VAVAV │ VAVAV │ VAVAV │ VAVAV
20. VAVAV │ VAVAV │ VAVAV │ VAVAV + seh
22. VAVVA │ VAVVA │ VAVVA │ VAVVA (chapa)
23. VAVVA │ VAVVA │ VAVVA │ VAVVA + seh
25. VAVAV │ VAVA │VAVVA │ VAVA (yak rasteh, yak chapeh)
26. VAVAV │ VAVA │VAVVA │ VAVA
27. VAVAV │ VAVA │VAVVA │ VAVA
28. VAVAV │ VAVA │VAVVA │ VAVA + seh
30. VAVAV │ VAVA │VAVVA │ VAVA (chap o rast)
31. VAVAV │ VAVA │VAVVA │ VAVA
32. VAVAV │ VAVA │VAVVA │ VAVA
Some compositions are much easier to perform with parandkari than others. The naghma in Talang used by Rahim in this example is commonly employed in Afghanistan as a repetitive accompaniment to a tabla solo in Tintal.