Is this C# and D# played together? It sounds weird/out of key, so wasn't sure.

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Edit: enter image description here

  • there are 2 notes - and only one sharp: ahead of D, so this D#. Commented Apr 29 at 8:39
  • 2
    One of the reasons it "sounds weird," if you play it correctly, is the dissonance between the left hand's F sharp and the right hand's C natural. That's a tritone Commented Apr 29 at 12:36

3 Answers 3


Since there is no key signature in your image it could be one of two things. First, the sharp symbol only applies to the D. If there is a C# in the key signature then you do you play C# and D# simultaneously. If there is no C# in the key signature or another C# within the same bar before this then you play C natural and D# simultaneously. It is better to include at least an entire line when you post an image for context.

Since the chord above is a G#7 then it would make sense for it to be a C natural, which is B# enharmonically, the 3rd of G#7. The D# is the 5th of G#7.

EDIT: Based on your more complete image it is definitely C natural and D# simultaneously. This however is poorly spelled as the correct note to match the chord symbol would be B#, not C. B# would also make the interval look like a 3rd, which is what it actually is, not some type of 2nd.

  • 1
    Ah sorry my mistake new here, I added it as an edit above ^^ Thank you!
    – Fake Name
    Commented Apr 29 at 0:05
  • @FakeName Welcome to the site. Please remember to upvote answers like this one that you find helpful.
    – Aaron
    Commented Apr 29 at 0:13

The core question of what to play is answered by John Belzaguy, so I'll just address the notation itself.

Accidentals apply individually to notes, so for C#-D# there would be a second sharp sign next to the C.

Example of two sharp signs

Similarly, for a C#-D chord, one would put a sharp on the C space and nothing on the D line.

Example of C#-D

And, of course, the accidentals needn't be of the same type. One could have Cb-D#, for example.

Example of Cb-D#

This also applies in the left hand, where F#-G# accompanies the C-D# in question.

Going one step further, suppose the key signature included C#. In that case, the chord in the original question would be written with a natural sign for the C.

Example of C-D# with natural sign on C

  • 1
    And also, perhaps, the John Belzaguy's "correctly spelled" version: B#/D#?
    – Mycroft
    Commented Apr 30 at 15:16
  • @Mycroft It's a good idea. The link to his post is intended in that spirit, since I prefer not to duplicate his post here.
    – Aaron
    Commented Apr 30 at 15:35

Simple answer. A sharp sign will be centralised along the line (or space) it's applying to. The same goes for flat signs, too, although there, the belly of the 'b' signifies whether it's applying to a line or a space.

The subtle difference is a key signature, where the same basic rule applies, except that a sharp on the top line, treble clef, for example, will mean every F will be sharp, regardless of its octave.

Agree with John that the C displayed ought to be B♯ in order to comply with the G♯ chord that accompanies that dyad. It would then make it pretty obvious that it's an interval of a third - which it actually is.

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