Hey guys; so I'm at a really "weird" place in terms of what "level" I'm at. I began playing the piano by ear at 2 years old, picking out the chords and notes from a melody on a local commercial I kept seeing (I still remember the song actually...). I had very few lessons growing up, but enough to learn some proper hand techniques.
I continued to compose my own stuff, playing by ear my entire. I still can't read sheet music all to well (it's gotten a lot better since I've been studying a bit as I've had free time over the past 6 months, but it still isn't intuitive. I have to find key notes that I know solidly on the staff as reference notes and count lines and spaces... and total there are about 4 reference notes I use).
So I've been studying with a composition instructor counterpoint, melody, and composition (he's not a piano instructor). This, coupled with school stress has made me want to take up classical piano playing again.
I'm working on two songs, Chopin's prelude No. 15 (no other song I've ever played has ever profoundly moved me...) where I've been pouring over every note, studying the 3 (sometimes 4 I think) competing melodies... and thoroughly paying attention to my dynamics (not in terms of right versus left hand, but in terms of each note, as I really feel like that constant A flat's volume needs to in general just under the melody's volume, and slightly more staccato, while the middle harmonic/accent voice I think should be played under everything else).
The second piece I'm working on is Chopin's Fantasy impromptu (which I'm actually finding easier than prelude No. 15... as there is less intricately dynamic counterpoint... at least in the beginning. This song seems to be more "right versus left hand.")
So the first song, I feel like I'm really getting the dynamics down, and the pedaling; but I have some bad tendencies. In some of the phrases the right hand plays both the main melody and the middle harmonic voice. I'm having trouble separating the dynamics of my thumb and pinky. The pinky plays the melody, the thumb plays the middle voice. The pinky should be louder but I keep playing them the same volume. If I roll the two voices I find it much easier to achieve the dynamic, but Chopin didn't notate that so I'm thinking... I shouldn't take the easy way out.
So what can I do to help develop dynamic independence of my fingers? (Incidentally I don't seem to have a problem changing dynamics per finger with my left hand).
As for the impromptu piece, I started this yesterday. I've never played 3 against 4 before. I looked up some youtube videos, and after practicing impromptu really slowly for about 10 minutes, was able to play the 3 against 4 pretty easily and almost intuitively. I speed up the song to the proper speed, and it "feels" out of control. I've recorded myself playing it using a midi keyboard, and then slowed the playback about 80%, and at the high speed the rhythm is almost perfectly matching up where it should, but it still feels like I'm just playing a mess of notes (even though upon playback it doesn't sound that way... barring of course improper dynamics and lack of pedaling as you do when you're just learning a piece).
I want to be able to play rhythms like this easily and intuitively so I can know and not guess or hope that the rhythm is right. Are there exercises or slower pieces that I can practice on top of impromptu?
P.S. I have tried working the left and right hands very slowly together, and speeding up. I can speed up to only a certain point before I seem to hit a cap. When I get to higher speeds from a slow speed in this song, the rhythm, while I believe technically correct, sounds really disjointed and lacks continuity. If I just start the song at the proper speed, everything seems to fall into place. I'm not sure what the means :/
Thanks guys for any help and advice! Sorry for the overly long post

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