“Accidentals in music” sounds like some kind of mistake, right? But the term “accidentals” actually means something quite different in music, and accidentals are an essential ingredient in reading and writing music. In this article we’ll explain what is meant by the term “accidental” (in the music sense).
Accidentals in Music: What They Are
Accidentals are simply sharps, flats, and naturals that need to be written into music in order to indicate a note that is not already indicated by the key signature. Pretty easy, right? An accidental is literally a written-in sharp, flat, or natural symbol. But let’s make sure we really know what that means, because there are a couple wrinkles in this explanation that we should fully understand.
In the example below we are in the key of E-flat major. We know this because it is indicated by the key signature, which contains 3 flats. (And we may also know the little trick to help us read flat-key key signatures: find the 2nd-to-last flat in the key signature and that is your major key).
Notice that there are no flats (or sharps or naturals) in the four measures of music above. Why? Because the key signature tells us that if we encounter any ‘B’s, ‘E’s, or ‘A’s, they are to automatically be played as B-flats, E-flats, and A-flats. So, besides the key signature itself, there are no accidentals in this musical example.
Now let’s look at another example:
What do we see in this example? Well, you should see a bunch of accidentals (i.e., sharps, flats, and/or naturals that indicate notes outside of the key signature). How many do you see in total? If you said 7, you’re right.
Now, some of you might be saying, “Hey, wait a minute. I see another accidental in the bass clef of measure 4. The one in parentheses!” Interesting that it’s in parentheses, right? That’s because this is what is referred to as a courtesy accidental. So if you saw 8 accidentals in the example, you’re also right. But let’s clarify.
Accidentals in Music: Courtesy Accidentals
Courtesy accidentals are just what they sound like – a polite favor. You see, the flat symbol in the bass clef of measure 4 does not have to be written. The note would be an ‘A-flat’ even if the accidental were not there. The parentheses indicate that the accidental is there as a courtesy reminder. It’s as if the music is saying “Hey, even though you just played an ‘A-natural’ in measure 3, that measure is over and now we’re back to automatic ‘A-flats’ as indicated by the key signature.”
Which brings us to another key piece of info: accidentals ONLY last for the one measure in which they appear. Once that measure is over you revert back to the sharps or flats indicated by the key signature. And accidentals ONLY affect the particular line or space on the clef in which they are written. That’s why in measure 3 of the example above we needed to use a ‘natural’ accidental for the ‘A’ in the bass clef as well as the ‘A’ in the treble clef.