Good light and a good angle to take a shot of the piano.
Since this is a closeup, the attention is drawn to the man/pianist more than the piano.
Your title suggests that you wish to accentuate the piano, not the man.
A "conceptual cropping" would then be more suitable i.e. try to zoom out a bit.
If you allow more window behind the piano, the vertical light will draw the eye down in a linear direction to the piano so that the accent is on the piano not on the man. Close cropping as you have done here makes it a portrait.
It all depends on your intent.
As it stands now, we see a balding man a wintercoat sitting by a piano. Sometimes a human element enhances a shot, sometimes it distracts. Its a fine balance. A young woman's silhouette by the window, or tracing the keyes with her fingers, or a child by a piano would be more charming... just a suggestion, and only my opinion.
Keep up the good work.