Every day brought further evidence of how well prepared Mozart was for music. He could distinguish and point out the slightest differences between sounds; and every sound which was out of tune, or simply harsh and not softened by a chord, was torture for him. Thus during his earliest years, and even up to the age of ten, he had an utter horror of the trumpet as long as it was not simply accompanying a piece of music; whenever he was shown the instrument, it had much the same effect on him as it would have on other children to turn a loaded pistol on them in fun. His father thought he could cure this fear by having the trumpet played in his presence, despite the young Mozart’s pleading to be spared this torment; but at the first sound he turned pale and fell to the floor; and he would no doubt have had convulsions if the playing had not promptly been stopped.
The trumpeter was the famous Schachtner, “trumpet of the Archbishop’s music, a great friend of the Mozart family” [for whom Leopold certainly wrote his trumpet concerto].
“One of the people to whom the young Mozart was [nonetheless] most attached…”