flats sharps naturals question

[daffyduck]

 Hi!
 If beside the treble clef there are flat or sharp signs, then those notes will be flats or sharps unless they have a natural sign right? The first question is, what is the name given to those flats and sharps at the beginning? But my main question is, if there is a flat on the E in the beginning, and then in the middle of the piece there is an E natural, does this mean all the following E's will be natural until one has a flat sign? Or does the natural only affect that one note? Or only until the end of the bar?

 Thanks

[pianowolfi]

Hi!
 If beside the treble clef there are flat or sharp signs, then those notes will be flats or sharps unless they have a natural sign right? The first question is, what is the name given to those flats and sharps at the beginning?

That's called the key signature.

But my main question is, if there is a flat on the E in the beginning, and then in the middle of the piece there is an E natural, does this mean all the following E's will be natural until one has a flat sign? Or does the natural only affect that one note? Or only until the end of the bar?

Until the end of the bar.

Welcome to pianostreet

[daffyduck]

Thank you!

[daffyduck]

 Ok now I'm confused... on the left hand the key signature is E, A and B flat. On one of the bars the first E is natural. Then there are 3 Es without any sign (natural or flat), then there is another with a natural. All 4 in the same bar. Does this mean the 3 in between are flat? Because if they're natural why put the natural sign on the 4th?

[pianowolfi]

Ok now I'm confused... on the left hand the key signature is E, A and B flat. On one of the bars the first E is natural. Then there are 3 Es without any sign (natural or flat), then there is another with a natural. All 4 in the same bar. Does this mean the 3 in between are flat? Because if they're natural why put the natural sign on the 4th?

In principle it does mean that all four are natural. Maybe there are two voices? Can you post a picture of that part of the score or tell us which piece and bar number?

[daffyduck]

 It's chopin nocturne op9 nº2, first and second lines. I can post a picture but I don't know how. If you have it, notice also on the second line, the D has a natural even though the flat was from the previous bar and isn't in the key signature, why?)

[pianistimo]

as i understand it, if you have something in a previous bar (measure) and there's a barline - everything is cancelled EXCEPT what is in the key signature.  therefore - a natural sign is merely telling you to remember that it is cancelled.  they're doing you a favor by reminding you. 

[pianowolfi]

as i understand it, if you have something in a previous bar (measure) and there's a barline - everything is cancelled EXCEPT what is in the key signature.  therefore - a natural sign is merely telling you to remember that it is cancelled.  they're doing you a favor by reminding you. 

Right. That's a very common practice.

Left hand m. 1 (measure one): E^b throughout; m. 2: E natural throughout; m. 3 E^B and D natural; m. 4: E^b and D natural throughout; m. 5: E^b and D natural throughout. mm. 1 and 5: C^b= same key as B. Hope this helps.

[pianochick93]

I also have a question regarding sharps and flats. If, say, the piece is in F major, and there is a B that has a natural sign, and then a B an octave above, also with a natural sign. Is this just to remind, or is it because a natural in one octave doesn't affect another octave?

Thanks. I have a feeling it's just to remind you, but I wanted to be sure.