Music Theory: Time Signature

Have you ever heard someone count in a piece of music? You know, counting the beats. You might have heard a “one, two, three, four” or a “a one, a two, a one, two, three, four!” just in the lead up to the start of a song? Well, what are they counting?!

They’re actually counting the beats. Most music has it’s beats grouped into fours (one, two, three, four, one, two, three, four…etc…) but other groupings do happen. We call these groupings a “bar”, and when we write music notation (or even tab) we divide the stave (lines that the music is written on) into bars with “bar lines”.

Here’s an example of what I’m talking about:

See how there are vertical lines every so often? Those are the bars, and between each of those lines we have a set number of beats.

How many beats? Well, this is where the time signature comes in to it. At the start of a piece of music, you’ll usually find a set of numbers:

See the two fours on top of each other? These numbers are the “time signature” for the piece of music or song. The top number here tells us that there are four beats to each bar. So we would count this as: one, two three, four, one, two, three, four…and each group of four fits into the music between the barlines (so here we have three bars, each four beats long).

Note Durations

The other number in the time signature, the one underneath, tells us which type of note to write for one beat.

So, in our example “⁴₄” is telling us that there are four crotchets (or quarter notes) for each bar. Which would look like this:

…obviously that’s not our only option for the rhythms of these bars, you would probably see (or use) a combination of different note lengths that add up to the same as four crotchets.

Different Time Signatures

Other examples of common time signatures include:

³₄- 3 beats per bar, each beat being equal to a crotchet (or quarter note)

²₄- 2 beats per bar, each beat being equal to a crotchet (or quarter note)

…so a 4 at the bottom means each beat is a crotchet (or quarter note)…

⁶₈- 6 beats per bar, each beat being equal to a quaver (or 8th note)

⁵₈- 5 beats per bar, each beat being equal to a quaver (or 8th note)

…and an 8 at the bottom means that each beat is equal to a quaver (or 8th note)- a quaver being half of a crotchet…

³₂- which would be 3 beats per bar, each beat being equal to a minim (or half note)- the “Sarabande” theme tune that I use for the outro to my YouTube videos is in ³₂.

Basically, the rule is that the top note is how high to count for each bar, and the bottom note tells us what type of note to write. As we double the bottom note, the length of note that we use for the beat shortens by half.

June 24, 2011 at 8:00 am | Music Theory | No comments