He felt a paralysing conviction that Falbe's judgment, whatever that might turn out to be, would be right, and the knowledge turned his fingers stiff.

From the few notes that Falbe had struck he guessed on what sort of instrument his ordeal was to take place, and yet he knew that Falbe himself would have been able to convey to him the sense that he could play, though the piano was all out of tune, and there might be dumb, disconcerting notes in it.

There was justice in Falbe's dictum about the temperament that lay behind the player, which would assert itself through any faultiness of instrument, and through, so he suspected, any faultiness of execution.
He struck a chord, and heard it jangle dissonantly.
"Oh, it's not fair," he said.
"Get on!" said Falbe.
In spite of Germany there occurred to Michael a Chopin prelude, at which he had worked a little during the last two months in London.

The notes he knew perfectly; he had believed also that he had found a certain conception of it as a whole, so that he could make something coherent out of it, not merely adding bar to correct bar.

And he began the soft repetition of chord-quavers with which it opened.
Then after stumbling wretchedly through two lines of it, he suddenly forgot himself and Falbe, and the squealing unresponsive notes.