The photo of Amir Jan Khushnawaz shows the body position for playing the rubab. The player sits cross-legged on a carpet or thin mattress in an upright posture with a straight back. The instrument rests on the right thigh, with the deep groove between the lower and upper chambers parallel with the thigh, so that the rubab is pushed forward about 45° relative to the player's body. The head of the instrument is at an angle of about 20° up from the floor. While the rubab can certainly be played sitting on a chair, the cross-legged position is optimal from an ergonomic point of view.
Rubab playing requires the use of mainly two fingers, the 1st finger and the 3rd finger, see the photo of Amir Jan. Some limited use is made of the 2nd finger, and the 4th finger is not normally used at all. The string should be pressed down ('stopped' is the technical term) by the finger just below the fret in order to obtain a clear sound. The fingernails should be relatively short to aid clarity. Special legato techniques, such as hammers and pulls can be used. In the hammer, the 1st finger is used to hold one fret, while the 3rd finger strikes a forceful blow on a fret above, producing a clear tone. In the pull the 3rd finger is quickly removed from the string with a slight lateral pluck, leaving the 1st finger taking a fret below. In the damped hammer the 3rd finger lightly touches the string in a way that hints at a note above but does not fully realise it. Sometimes the lower note in these legato techniques is given by an open string (Ni1 or Ge or De).
The rubab has four frets, which allows a range (ambitus) of an octave plus a wholetone to be played with ease. Beyond that means getting into the unfretted range of the instrument, which is much more difficult. A modern virtuoso like Homayun Sakhi seems comfortable throughout the unfretted range of the instrument, on all three strings. Lesser mortals are restricted to the first string, up to about Pe2. Khalid Arman has devised a new model of rubab with fixed frets all up the fretboard, more like a guitar. This makes it much easier to play in the higher range.
The rubab is played with a wooden, bone, or horn plectrum (shahbaz) and requires a special posture for the right hand, with the wrist sharply flexed. The flexed position can be seen in the photo of Amir Jan, and in the diagram
The plectrum is held between the thumb and 1st finger. The edge of the nail of the 1st finger adjacent to the thumb should be filed down a little so as to improve grip on the plectrum. The flexed posture of the right wrist produces an imbalance between the downstroke and the upstroke. The downstroke is not flat across the string, but also downwards towards the velum. It has the weight of the hand behind it, and a longer distance to travel, and has a more powerful sound than the upstroke, especially if the hand also impacts on the velum, adding a certain percussive element. When striking the 3rd string the plectrum comes to rest on the 2nd string, and when striking the 2nd string the plectrum comes to rest on the 1st string. But when striking the 1st string the plectrum should not come to rest on the velum. The imbalance in the sound of the downstroke and the upstroke means that different permutations of down and upstroke produce subtly different rhythmic patterns, something that is exploited in rubab playing, with its great variety of rhythmic patterns.
Right hand posture and down & up strokes (multi-angle video)
In making the down stroke on the rubab the hand impacts on the velum, giving an added percussive element to the overall sound. Right hand percussion effects are used in playing other Afghan lutes such as the dambura and the 3 stringed Herat dutar, where the right hand scrapes across the wooden belly of the instrument while strumming the strings. In recent years there had been a tendency to reduce or eliminate velum percussion, by adopting a right hand posture with the 3rd and 4th fingers curled up, to avoid their touching the skin on the downstroke. This allows the velum to vibrate more freely. Clearly there are rich possibilities in modulating between heavy impact, and no impact at all. Downstrokes on the 3rd string may also involve one or more of the adjacent long drones.
Some use is made of strumming down across the sympathetic strings to provide a multi-drone effect, particularly in as a punctuation in playing the slow introduction in free rhythm (shakl). The shortest sympathetic string (the sim-e barchak) is used as a high drone in a special right hand technique called parandkari, Use of the barchak string as a high drone is discussed in Chapter 6.
The plectrums (shahbaz) used by Afghan rubab players vary widely in shape, size and material and there is no standardization. One becomes accustomed to a particular plectrum, but a plectrum can easily get mislaid, in or out of performance, and it takes a while to get used to another one. I have found it expedient to use a standardized guitar plectrum, and to have a number of them in a little box by my side when I am playing, so if one is mislaid an identical substitute can be found immediately. The type of plectrum I use is the Jim Dunlop Big Stubby 3.0 gauge, and I purchase them by the dozen. This is a rather thick plectrum normally used for electric guitar. The shallow indentation on each side help to maintain a good grip. Roughing up the plectrum with sandpaper also helps to secure adhesion. I also use an elastic medical wristband around my right wrist. This provides support and comfort, and reduces the effect of the edge of the belly of the instrument cutting into the wrist, causing numbness.