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Lesson 8: Natural sign, more on accidentals and key signature

Video transcript

the sign for a natural looks like this if a note does not have a flat or sharp before it it is always a natural with two exceptions the first exception is when an accidental is placed before a note that note will always sound that way through the entire bar once the bar line appears the note will return to a natural unless the accidental sharp or flat is added again let's look at the last movement of Beethoven's fifth symphony once again notice the f-sharp in the second bar of this excerpt and then after the bar line the sharp needs to be added again in the fourth bar of this excerpt we notice that the f-sharp carries through the bar the second exception is what is called a key signature a key signature is a sharp or a flat or multiple sharps or multiple flats that are placed at the beginning of a line of music between the clef and the time signature and then at the beginning of the line of music following for an example let's add one shop to the key signature first the staff then a clef let's use the treble clef then a single sharp and then the time signature let's use four for the fare shop is always an F and in treble clef is placed on the top line the fifth line in a bass clef the first sharp is placed on the fourth line the result is that any time and F is played anywhere in this piece the F will be altered to an f-sharp let's play for F's 2 in the bass clef and 2 in the treble clef now we add a sharp side to the beginning of the staff and all of the F's now become f shops let's look at one flat in the key signature the first flat is always a B in treble clef is on the third line in bass clef it's on the second line again that means that every B written will be a b-flat without the need to add the flat sign before the note again it's important to learn that if we have sharps in the key signature we cannot also have flats in the key signature if we have flats in the key signature we cannot also have sharps in the key signature if we are playing a work with one sharp in the key signature of course we know that sharp is always an F but the composer would like to have an F natural played a natural sign would have to be placed before the F let's look at the opal part during a section of the Brahms academic festival overture we first noticed that Brahms writes a sharp sign at the beginning of the line on the fifth line in treble clef of course we know also that that indicates that all FS are now F sharps since Brahms wants an F natural in this bar he has to add the natural sign he also does this in the first violin part the same applies to flats let's look at Tchaikovsky's Fourth Symphony last movement notice that the first flat is always a B and in treble clef it comes on the third line in the melody played by the flute Tchaikovsky wants a B natural rather than a B flat so he must put a natural sign in front of the beat