Metric modulation

Metric modulation is a fancy way of saying that we're changing how we count time in music. You know how we like to count to four when we're dancing or singing along to a song? Well, sometimes musicians like to mix things up and count to a different number or use a different rhythm. This is where metric modulation comes in.

Imagine you're playing a song and you've been counting to four this whole time. Suddenly, you want to change the rhythm and count to three instead. But you don't want to just stop playing and start counting differently. Instead, you use metric modulation to smoothly transition from counting to four to counting to three.

To do this, you choose a note value (like a quarter note) and give it a certain length of time in the old rhythm (four beats). Then, you decide how many of those note values will fit into the new rhythm (three beats). Let's say you decide that two of the old rhythms (quarter notes) will fit into the new rhythm (three beats).

So, when you're playing the old rhythm, you start by emphasizing every fourth beat. But as you slowly transition to the new rhythm, you start emphasizing every sixth beat instead (which is where the two old rhythms fit into the three new beats). This creates a smooth transition from the old rhythm to the new rhythm, without any awkward pauses or stops.

And that's pretty much what metric modulation is all about – changing the way we count time in music by smoothly transitioning from one rhythm to another.