Raff's most famous pupil was the American composer Edward Macdowell who had travelled to Europe for his musical education. In 1879 he joined the Frankfurt Hoch Conservatory to study piano with Carl Heymann but Raff saw his greater potential and took him into his own composition class. He soon became his favourite pupil and he repaid Raff with equal devotion and respect. Their first meeting was his initial interview to join the Conservatory, when he was 18. Raff was in a typically irascible mood and the meeting was, in Macdowell's own words, "... not promising".
"Heymann took me to him and told him, among other things, that, having studied for several years the 'French School' of composition, I wished to study in Germany. Raff immediately flared up and declared that there was no such thing nowadays as 'schools' - that music was eclectic nowadays; that if some French writers wrote flimsy music it arose simply from flimsy attainments, and such stuff could never form a 'school'. German and other writers were to be criticised from the same standpoint - their music was bad, middling or good: but there was no such thing as cramping it into 'schools' nowadays, when all national musical traits were common property".
Raff soon came to recognise Macdowell's great talent and told another pupil that he "expected great things" of Macdowell. He predicted "Your music will be played when mine is forgotten". For much of the 20th. Century, however, they were both remembered primarily only for trifles: Raff's Cavatine and Macdowell's "To a Wild Rose".
Macdowell held Raff in great respect which bordered on awe. The American's 1st. Piano Concerto owes its existence to his reverence for Raff. As Macdowell sat listlessly at his piano in his rooms one day he was taken aback to find Raff at his door...
"The honour simply overwhelmed me. He looked rather quizzically around at my untidy room and said something about the English translation of his Welt Ende oratorio (I found out after, alas, that he had wanted me to copy it in his score for him; but with his inexplicable shyness he only hinted at it, and I on my side was too utterly and idiotically overpowered to catch his meaning); then he abruptly asked me what I had been writing. I, scarcely realising what I was saying, stammered out that I had a concerto.
He walked out on the landing and turned back, telling me to bring it to him the next Sunday.
In desperation, not having the remotest idea how I was to accomplish such a task, I worked like a beaver, evolving the music from some ideas on which I had plans at some time to base a concerto. Sunday came, and I had only the first movement composed. I wrote him a note making some wretched excuse, and he put it off until the Sunday after. Something happened then, and he put it off two days more; by that time I had the concerto ready".
Soon after, Raff took Macdowell to Weimar to play the Concerto to Liszt, who was greatly impressed and to whom it was eventually dedicated. Contrary to the view of one of Macdowell's biographers that he "ruined his talent by studying with Raff", the older man was entirely responsible for Macdowell emerging as a composer of worth at all. He encouraged him to be individual, saying "Pay attention to the masters: Mendelssohn, Schumann, Brahms - but find your own voice".
Although he left the Conservatory after two years, Macdowell stayed in constant touch with Raff. When Heymann had to leave the Conservatory in 1881 because of illness, Raff recommended Macdowell as his successor - but the appointment was blocked by the opposition of some of the other professors there. As with many of his students, Raff's unexpected death affected him deeply:
"Only the day before the terribly sudden event I had walked part of the way home with him from the Conservatorium. As I bade him goodbye I noticed that his hand was very hot and dry and that his eyes seemed unusually bright. The next morning I was greatly shocked when I heard that he had been found dead in his bed by the barber who went every morning to shave him".