The bow change · From Zero to Mozart

A whole bow runs out. At the frog and at the tip you have to turn the bow around and go the other way — and a good change is one nobody can hear. Two things can give it away: a gap (a hole in the sound) or a bump (a little unwanted accent). The job is to have neither.

What a clean change is

Think of it as the bow turning a corner, not stopping and restarting. Three things make it smooth:

Keep the bow moving through the turn. The commonest fault is slowing down into the change and speeding up out of it — that dips the sound at every join. The speed stays even right through the corner.
Let the hand and wrist take up the reversal. The arm changes direction a fraction before the hand does, so the fingers and wrist "give" and absorb the jolt. They're the shock absorber. A stiff hand makes a hard corner.
Match the weight across the change. An up-bow starting at the frog wants more weight than feels natural; a down-bow arriving at the tip wants more arm. Otherwise the new stroke starts weaker than the old one ended.

54 bpm

How to play it

Half-bows in the upper half. Don't stop at the change — let the wrist and fingers roll through it while the arm reverses. If you hear a click or a gap, you stopped.

Four half-bows on open A — down, up, down, up — using the same part of the bow each time (say the upper half). Every note the same length, the same volume. The only event is the direction change, and it should be inaudible.

Hear the difference

Play the same four notes twice: first deliberately stop the bow at each change (you'll hear four separate notes with silence between — that's a staccato, and it's a real stroke, later). Then play them joined, turning the corner without stopping. The second version is one unbroken sound that just changes direction. That's legato, and the bow change is the thing that makes it possible.

Try it

Try

On the open D string, play slow half-bows near the frog, down and up, and put a finger of your left hand lightly on the bow stick near the frog so you can feel it reverse. Feel how the fingers flex as the direction turns. Then do the same near the tip. The change near the frog needs the most give; near the tip it's smaller.

The usual mistake

Squeezing the bow at the moment of the change — clamping the fingers down to "control" it. A clamped hand can't absorb the reversal, so it passes the jolt straight to the string as a bump. Keep the hold loose right through the corner; the bow almost turns itself if you let it.