This is an excerpt from Etude in C# minor.

What do the little X's next to the notes mean?

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Do I have to play these any special way? Is it an accent mark?

  • 3
    Please don't delete duplicates. They help others find this question and the other answers on the site. – Dom Apr 30 '18 at 2:56
  • Answer: It is a double sharp. F goes ## to G. – ghellquist Apr 30 '18 at 19:50