How to practise a passage faster when you hit a speed wall

Everyone has a passage like this. Fine at 80%, fine at 85%, in pieces at 90%, every day for a fortnight. The instinct is to keep attacking 90%. That is usually wrong, and it is worth knowing why before spending another week.

First, find where the wall actually is

Play it at 95% of the tempo that defeats you. Not 90, not 85. If it fails there too, your wall is lower than you think and you have spent a week practising failure. If it holds cleanly, the wall is real and narrow, and the rest of this applies.

The step size is usually the problem

Most people climb in jumps of five or ten percent because those are round numbers. The body does not care about round numbers. A 3% step is about two clicks of a metronome at 120 bpm: small enough that each stage feels like the last one, which is the entire point. Ten percent feels like a new piece.

1. 1Set Start below comfortableIf you can play it at 80%, start at 75%. The first stage should feel easy.
2. 2Set Step to 2 or 3 percentYou want each stage to feel identical to the last one.
3. 3Set Every to 3 or 4 repeatsLong enough to settle, short enough that the session is not an hour.
4. 4Set Target above the wallA few percent past it. Not reaching it today is information, not failure.

When the fingering is the wall

Some fingerings work slowly and stop working quickly. A stretch that is comfortable at 70% may not have time to release at 95%. A position shift that is fine when you can look at it becomes impossible when you cannot.

The tell is a wall that does not move at all across a week of correct practice. Walls made of unfamiliarity move, slowly. A wall made of a bad fingering sits exactly where it was on day one. When you see that, stop drilling and re-finger.

Where the trainer runs

It runs on the loop, so set A and B first — ideally around the one beat that fails rather than the whole phrase, for the reasons in the bar you keep missing.

Where the trainer runs out

It will not make playable a passage you have not learned. The trainer raises tempo on something you can already play slowly and accurately; used on a passage you are still working out, it just moves the failure around.

It will not fix musical problems either. A phrase you do not understand rhythmically will not become clear at 96% having been unclear at 92%. Work the rhythm out slowly, by ear, first.