Is it hard to learn piano at an older age?

Absolutely not. Learning to play piano at the age of 6-7, while extremely tough, will not be difficult at 12 or 13-years-old. At that age, the kids are learning to read the piano, and a lot of the keys are fairly easy at the 6 to 7-years-old level. Most of them will also be reading in their own right and will be able to do the things that adults can do, and many even do a bunch of the new things as well, like playing the piano with a partner!

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I will be using an iRig 3/4 scale to play the first movement of this piece. Here, it is:

D D A♭ G# G D A♭ F F C C D

Notice the “B♭” notes? For scale tuning, we use the letter “B” to indicate the “C” degree within the scale. In the A Minor scale, there is 2 B♭ notes. So, if you want to play the “D”, you have to play two B♭ chords at the end of the piece. The 1st and 2nd B♭ (lower one) are the same, but the 3rd is a different B♭, and I will keep that in mind.

So, I want the B♭ to be the root of the third chord (A♭), D and A, which is the first major seventh chord, “The A”. Then I want it to be the root of the second chord, E♭, and the 1st is a D♭, the D♭ being the first A♭ note in that scale. So, after the 1st chord, I want it to be the root of the 2nd chord, G#, and the next major seventh chord, “The B”. That is, we want to make sure that the third chord, D and E, are both the root of the 2nd and 3rd chords.

Now, to play G# on the E♭ chord, I’ll need 3 B♭ keys in the scale. The B♭ keys are G (in F major), a (in C major) and a♭ (in G major), and therefore in C major, D and E are the 3rd and 4th keys in D minor pentatonic scale. The third key in the scale is G#, and the fourth key is D♭. So