WHITE SPACE: The judicious use of positive space and negative space in this image allows for a hidden letter to reveal itself. The positive space, contrasted by the negative space makes it seem as though another letter is present, completing the word.
Shapes of instruments are commonly used in logos representing music related businesses but his one is quite clever. I believe '11' is the name of this music playing/ selling establishment and it's elegantly incorporated into the black keys of the piano. The visual is sophisticated and gives a classy, high end feel.