THE FOURTH FINGER
One of the main problems in fingering for the double bass is with the use of the fourth finger which is the weaker that the others finger.In fact in the German fingering [(1)-(2)-(3-4)], which is used in some orchestral playing, the little finger is supported by the third finger, but to the detriment of agile execution, because this isn't really a natural position. It is easy to see this just by looking at the palm of your hand and noticing how the 2nd and 3rd fingers are closer than the 3rd and 4th.
The [(1)-(2-3)-(4)] fingering,which is most commonly used, leaves the fourth finger more freedom to operate, but the little finger is notoriously weak, and therefore in need of special exercises to strengthen it. With these following exercises I have tried to outline a path not only to strengthening the little finger, but also to working on intonation, and the use of the bow, which is of course an essential part of any double bassist's technique.
The first illustration shows the hand position for the interval of a perfect fifth (Eb 1 - Bb 4) relating to exercises 1,2 and 3.
The second illustration shows the interval of a minor third (F 4 - Ab 1). Here it is essential that the 2nd and 3rd fingers press together against the fourth or the first finger, and that they rise or stay down as the exercise requires.
The same positions should be applied to the A and D strings, and then to the E and A strings. It is very important, especially when trying exercises 3,4 and 5 not to force the action if the little finger starts to show signs of fatigue or stiffening up. In this case stop; take a break and carry on later. A little patience will pay off with good results.
Pic. 1 Pic.2