I am going to try to learn Rachmaninoff's C minor concerto for the piano, most likely simplified. I always love the song, but what is the correct way to play it at 7:10 of the video (measures 9 and 10 after rehearsal mark 10 in the score). I see a lot of videos that play that part softy or loud and hard expressing themselves. I know it doesn't really matter but what was the original way of playing it?
You can find a score to this movement here at IMSLP. On page 32 of the document, you'll see that this section is marked ff:
With that said, this is a reprint of a score from Muzyka, and it seems that the first publication was from Gutheil. To know with 100% certainty, you'd want to check the original Gutheil score (and the autograph score from Rachmaninoff, if that exists).
I have a Gutheil edition - it's marked ff. I don't think I've ever heard it played any other way. Rachmanioff's own recording is a bit subdued here - more mf than ff but I think that's because of recording technology in 1929. But his tempo is interesting - much faster than Wang's. It depends on whether you think of a march in 2 or 4. Rach is definitely in 2, Wang in 4. I don't have any other recordings to compare.