The Trick To Writing Harmony Lines

hey, welcome to 12tone! as music theorists, we often talk about harmony in terms of chords, scales, and progressions, but when it comes time to actually arrange a song, the word harmony often means something a little different. here, a harmony part is a secondary line that sits behind the primary melody. it can add power to a rock song, emotional depth to a ballad, or just complexity and texture to anything you want, but finding just the right line to complement your melody can be a little difficult. fortunately, there's a couple techniques that help make it a lot simpler. let's try an example. if we want to write harmonies for this, the first thing we need to know is what the chords are. what's the band playing? if you don't have chords yet, we've talked before about how to find them, but for the sake of simplicity, let's just say it's this. the next question is range. where are we going to put our harmonies? this largely comes down to instrumentation. of course, you don't want to write parts that your instruments can't play, but it actually goes deeper than that. you see, for some instruments, there's an inherent connection between pitch and power. because of the way a trumpet is played, for instance, higher notes take more air pressure, so it's difficult to play them softly. this means that whatever note is highest is going to be loudest and is going to come across as the main melody, so if you're working with brass or woodwinds, harmony parts should always be below the melody. in other cases, like guitars, violins, or especially the human voice, you have a lot more dynamic control, so the melody can stand out no matter where you put it. for our example, though, let's keep things simple and just do two voices underneath. with that out of the way, it's time to actually write our lines. let's take a look at our melody again. now the first step is to find chord tones. these already fit in with the chords behind them, so they're the easiest to work with. for instance, we're starting on an Ab, one of the three notes in F minor, so the harmony voices should probably just sing the other two, in this case F and C. most melodies are gonna have a lot of chord tones, and this one's no exception, so even harmonizing just those is gonna get you pretty close already. but it's not quite done yet. not every note in our melody is part of a chord. for instance, this Bb isn't part of F minor, so what do we do with it? well, this is an example of what's called a non-harmonic tone, in this case a passing note, and the simplest thing to do here is to follow the melody's shape. the melody is moving up by steps, so our harmony should too. that's easy to do in this voice, but in this one we have a problem. there's two different notes in between the chord tones. which one should we use? well, here we're saved by a helpful rule of thumb. in writing harmony parts, where you're going is usually more important than where you're coming from. if we're gonna have to jump somewhere, we'd rather just get it over with. this lets us step smoothly into the next chord voicing and preserves the melodic shape as best we can. but hold on, these three notes make a completely different chord from what the band is playing. normally we wouldn't want that, but here we're actually okay with it. it passes by too quickly to cause all that many problems. it actually sounds kinda cool. we can fill in the rest of the non-harmonic tones similarly, but then we come to this. this D gets held for a long time, way too long to do what we've been doing. the chords would clash and it would sound like a mess. instead, we're going to have to think of this as a tension, a note that's not part of the chord but works with it anyway, and when you're dealing with tensions, the best thing to do is just treat them like they're the next chord tone down. in this case, our D gets treated like a C, so our other voices sing a G and an E, and we're done. this is what's called tight harmony, where all the parts closely follow the shape of the main melody, usually within an octave. there's plenty of more advanced techniques, from voice leading and tensions to contrary motion and even secondary melodies, all of which we'll cover in future videos, but tight harmonies are an incredibly powerful, versatile tool, and really, most of the time, they'll get the job done. anyway, thanks for watching! if you want to help make these videos possible, please consider supporting 12tone on Patreon. you can also join our mailing list for scans of all our episodes, like, share, comment, subscribe, and keep on rockin'.