Today I’d like to say a few words about the bowing stroke we know in violin circles as detaché, or detached, as we would say in english. To be clear, what this refers to is the playing of one note per stroke of the bow, generally in the upper half of the bow, and without any space between the notes; that is, smoothly.
It sounds easy, yet to do it well is deceptively so, as any novice player will attest.
So, leaving off complications such as changing pitches or string crossing, let’s talk about the motions of hand and arm that enable it.
First, the bow hold ought to be relaxed and light, made relatively easy by the fact that the bow is largely ‘resting’ on the string – no need for counter-pressure by the little finger.
Second, the elbow joint must be free of any constriction. It is, after all, through the back and forth movements of the forearm that the stroke is largely produced, the upper arm and shoulder remain relaxed and passive.
Third, the wrist, though not required to flex much in a typical detaché passage, must remain supple and able to accommodate the movements of the forearm such that the bow remains straight and parallel to the bridge.
Now looking back at what I’ve said, you see that the words I’ve used to describe the movements and qualities of the various body parts (relaxed, light, supple) are all of a similar feeling; there is nothing stiff or forceful about producing a good detache. When one wants a bigger tone more arm weight is simply allowed to be transferred to the string by relaxing the upper arm even further. Only in fortissimo is it necessary to add downward pressure to the string.
All the best,