J. Anthony Allen explains the difference between tonicization, a brief detour to another key that returns quickly, and modulation, a genuine key change that lasts longer. Tonicization might last a few bars; modulation becomes the prevailing tonal center for an extended period. Classical music modulates often within a single movement, while modern pop rarely does, except 80s ballads.
Okay, down to business. So we're going to talk first about modulation. Now, before we get into that, we need to define really what a modulation is. Because we've talked about tonicization, right. But not modulation. And what is the difference between the two? It's actually a really tricky thing to figure out. So let's talk about it a little bit. Let's review what tonicization is. Tonicization is a change in the key, sort of. But only temporary. Right? It's when we might go to a new key for a couple bars and it just feels like a new key and then we go right back to our original key. So it's not a key change. We don't really change key. We just kind of flirt with a new key and then we go right back. So it's a brief moment of going somewhere else and then coming back. We call it a tonicization. Because what we're really doing is we're tonicizing another key for a minute and then leaving it behind. So we're saying we're. Let's say, hypothetically, we're in the key of G. Everything's going along in G really fine. We do something weird and all of a sudden we have this, let's say. Well, D would be the easiest, right? Because it's the five. So suddenly we do a big cadence in D and it feels like we're in D for a minute. We have temporarily kind of put a crown on D and said D is now the tonic. So we've tonicized D, we've made D feel like the tonic. But we're not going to stay here very long. And then we're going to take the crown off D and put it back on G and say G is the tonic. Just kidding. And we get back to G. So that is atonicization. Now, there's really no firm length of time. Like we say, atonicization is a brief moment of time of moving to a different place but then going back. But what does brief mean? Is that two bars? Is that one bar? Is that 12 bars? It all kind of depends on the context. So this is a very wishy washy kind of rule. So the question is, at what point does it become a modulation? A modulation is a change in key. Like we are going to a new key, and that is where we are. We're going to stay there. And we could stay in that new key all the way to the end of the song. Maybe at some point we'll probably come back to the original key, but maybe not. And we need to do it in such a way that it's going to feel really natural to be in that new key. So the big difference between tonicization and modulation is that tonicization is temporary. Modulation could be permanent. Modulation is a change in key. And it's fairly common in classical music. Not as common in popular music. Not as common as you would think. A lot of people say, oh, this song changes key when it really kind of doesn't. It's quite rare for a pop song to actually change key, except for, like ballads in the 80s they did a lot. But modern popular songs don't change key very often. But in classical music they do. They change key a lot. You know, you might have a seven minute piano sonata and it might change keys 10 times. That's totally normal because there's a lot of music happening in that seven minutes. And in order to keep things moving along, changing key is a nice way to make something feel like it's going somewhere. Right. So there are a couple rules that we can look at other than just the length of time to decide if something has modulated or if it's just a tonicization. So let's go to a new video and let's talk through those rules.
