accidental in one stave, note in both staves, apply to both notes?

[Derek]

I'm sure I've seen this question asked before, but I haven't found the thread that asked it. Say there's an A# below middle C in the treble clef, and there's an A below middle C in the bass clef, but it doesn't have an accidental. Do you play the A natural or A sharp? I'm assuming you play the A# in both staves?

[quantum]

In some cases the engraver forgets to put cautionary accidentals.  What is the harmonic context?  What is the chord with A# in both staves?  What is the chord with A-nat and A#?  What is the chord progression this lies in? 

[Derek]

Here's a picture of two beats where this occurs. It's in Scriabin's op 42, no 5. a semitone dissonance wouldn't be all that weird in this piece, though it is mainly traditional romantic harmony mostly.. I thought though perhaps the sharped notes could be considered passing tones. In other bars with the same figure transposed, they also start out with a chromatic passing tone (or escape tone perhaps? I don't know the proper term in this context), so maybe you do play the # in the right hand and the nat in the left hand. Not sure.

[Derek]

Fearing my picture of the notes in question was not clear enough I made a new picture circling the notes. There is a sharp on the note in the treble, and no sharp on the note in the bass, and as far as I can tell the notes are coincident. Do I play both notes or do I play the same sharped note in both hands?   My instinct is that you play both notes, since the focus is on the texture and the melody (in Scriabin op 42-5), and that frenetic inner figure has a lot of chromatic passing tones. It is difficult to hear what is actually going on in recordings, since a lot of pedal is used and most professionals play far too fast to really tell.

[Bob]

If it's Scriabin, I would think it's probably meant to be played as written. 

I could be wrong though.  I don't know the piece.  That they did it twice makes me think it's how it should be written.

You might contact the publisher.  See if there's an errate list for it.

[slobone]

Hard to tell what's going on here without knowing the key signature. But unless the key signature indicates differently, you'd play both notes as written. In answer to your general question -- accidentals only apply to the line they appear on. They don't apply to notes in the other hand.

Most likely what's going on is there are different harmonies in the bass and treble, so you might not even hear this as a dissonance. Chopin does the same thing actually.

[guendola]

Accidentals are valid for the staff only where they are written.
Accidentals only apply to following notes in the same measure.
Accidentals only apply to notes of the same pitch, not to notes of the same name but an octave higher.

Or shorter: An accidental applies to all following notes of the same pitch in the same measure and staff (no less, no more).

Standard piano notation: Left hand lower staff, right hand upper staff. Left hand ignores all accidentals for the right hand and vice versa. So if you have the middle c (c') sharp for the left hand but no sharp for the right hand at the same time, you actually play c-sharp and c.

Some Rachmaninoff scores have two staves for each hand (part of the famous c-sharp minor prelude for example). In this case even one hand can have the same note with and without accidental (in two different staves).


A lot of sheet music has courtesy accidentals, mostly the natural, which is a reading aid, nothing else.

I hope these comments help.