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How to Write an Instrumental Underscore Track

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Read Time: 17 min

In this tutorial we'll walk through the entire process of creating an instrumental composition, from the first sketches of an idea through to the final mix. Of course there are a thousand ways to write a piece of music, this is just one method.

You shouldn't expect to use this method for everything you ever write, but it should be helpful for you to see one process for developing a composition in this style.

Initial Planning

This is not being written to film, so there is no drama being dictated by the action on screen. In general I want the development of the piece to lead me where it wants to go, so I am only going to plan out a few things. I want to create a 1:30-2:30 minute instrumental track in an underscore drama/thriller style. The piece should feel mysterious with certain moments of interest. That's all the planning I'm going to do, we'll see where the rest leads us.

Also keep in mind that one of the goals for writing this piece is going to be getting it out quickly, so although we want to make it good, we'll also find good places to take shortcuts such as repeating sections or looping ideas.

Find an initial idea

The first thing I like to do is find some sort of basic fragment to get me started. I could spend days staring at a blank page/screen having no idea where to start, so the best thing for me to do is load up a sound and just start noodling. You can start with anything you like, though I generally try to lean towards instruments that are going to sound good as MIDI such as pianos, keyboards, harps, or mallet percussion.

Vibes sound intreresting to me at the moment, so I'm going to load up a straightforward vibes instrument in EXS. Add a touch of reverb for flavor and then I'll start just playing the keyboard to no click, riffing on different patterns and licks and trying to feel around for something that feels inspiring.

There isn't much of a science to it at this stage, but generally I'm looking for something with a few basic requirements:

  • Simple: I should be able to repeat it easily or transfer the idea to other sounds.
  • Interesting: Simple doesn't have to be boring. There should be at least something keeping the interest moving, perhaps a special rhythm or interval.
  • Short: I'm not trying to create a masterpiece by searching for a fragment, all I'm looking for is a little gem that will get me started on everything.

Here's what some of my noodling around sounded like:

After about 8 minutes of messing around I landed on this lick that I thought had potential:

What I like about this lick is both the bouncy rhythm of the first two beats (One - and a Two - and a Three) but also the tritone interval in the melody of the second two beats (E Bb Ab E). Notice the low Eb on beats 1 and 3 which is very grounding and steady. I also keep the sustain pedal down for the entire lick, which gives a washed out spacious feel.

I was not recording to a click, so I now I need to find the right tempo (feels like about 85bpm) and play in a cleaner version. I'll also quantize it and straighten out the velocities to all be the same by using the MIDI Region Parameters box in the upper left corner of the Arrange window.

Here's our cleaned up lick:

This is the only stage in writing the piece that we're going to spend time noodling around for an idea. From here on out the goal is to get the ideas out of our heads and into the session as quickly as we can. Trust your instincts. If you're hearing a cool piano line in your head, get it down and then keep moving forward. Hours can be wasted by going over the same two measures over and over until you think they're "perfect", but by this time you've heard the material so much that you've lost all perspective. Remember that music is linear and keep it flowing.

Start Creating an Introduction

Now that we have our initial idea we can start developing everything else around it. The simplest thing I can do is select my region, hit L, and have it loop into infinity.

By the fifth repeat it would start to drive me a little nuts, so let's start spicing it up. On the fifth measure I'm hearing a hard bass and drum hit, so I'm going to load up a bass and taiko drum patch and have them hit a long Eb.

The taiko hit is pretty dull, so let's spice it up by adding a 32nd note flourish into it. It wont be completely different but will add some more subtlety. Notice that I have the velocities increase until the downbeat is the loudest hit.

There are still several things we should do to make the introduction more interesting, but we'll save the fine tuning for later. It's important that we keep plowing forward and work on getting the big picture in place.

Develop an A section

By bar 9 we have heard plenty of the introduction and the vibes lick is starting to wear itself out a little, so we should pick things up by bringing in our main A material. I'm hearing strings on a simple melody line, which I'm going to play in over the vibes.

I'll flatten out the velocities, quantize the time, and use modulation to create dynamics and shape. See the tutorial on How to Create More Expressive MIDI Music for details on how to use modulation in this way.

Although this melody line is very simple, there are a few important things to notice. There is a rhythmic pattern with the Bb pickup going into descending notes. The third bar is the climax of the phrase, because not only is the B natural the most dissonant note in the pattern, the rhythmic pattern has also been violated. Rather than the dotted half note to quarter note pattern that we established, we have two half notes. Both of these elements make this measure the most tense, which also makes the long Bb feel at the end feel especially relaxed and at ease.

Notice that the melody is five measures long instead of the typical four. Not only does this allow us to breathe a little at that fifth measure, but it also is a subtle way to upset the perfect balance of even phrases which adds a touch of interest and instability.

Let's repeat this phrase, but this time instead of a declining melody I'll have it turn around and climb up, again saving the most dissonant note for the "climax" of the phrase before relaxing on the Eb.

Repeat the A section

Now that we have a two phrase melody we can consider that our A section. Since we've only heard it all the way through once, let's repeat it but this time we'll keep it interesting by intensifying the orchestration.

I'm going to leave two bars at the end of the first A section before beginning our repeat, which will function as a moment of breathe and add to the 'mysterious' quality we're going for.

I'm going to repeat the strings, but this time I'll double them with a spooky synth. I've chosen the Starry Night patch which is a preset in Sculpture. I'll raise it up an octave and the result gives the melody more longing.

Next I'll add more intensity to the overall feel by having the bass hit a low Eb whole note on every bar. The part itself is not very interesting, but it adds a sense of weight to everything around it.

The other thing that could use some variation is our tired vibes lick, so I'll try doubling it on harp to see if it changes it up enough. I'll have it up an octave and also very quiet, so it is just slightly felt.

So here's what we've got so far:

And what the session looks like: (see the sections that are literal copy pastes of earlier material)

It's still somewhat boring, but now we have an outline which is what matters at this stage.

Develop a B section

As I mentioned in the beginning, my target length for the piece is only 1:30-2:30. Since we're already at about 1:15, I don't really have time to develop an elaborate B section. On the other hand, the piece could use some sort of variation because just repeating the A section one more time would be pretty boring. So to solve this problem I'll create a very short B section that is based on the A material with only some very small changes.

The most obvious thing I can change is the harmony, which has been on an Eb pedal since the very beginning of the piece. I'm not going to get complex here at all. Simple harmony changes can be just as effective as less common ones, so I'll just have the B section start on an Ab. To do this I'll have the bass lay down a nice fat Ab and adjust a few of the pitches in our vibes ostinato to reflect the change.

I'll do the Ab for two measure and then back to Eb for two measures. Notice how the Ab (the iv chord) feels like it is lifting us up, and then the Eb is putting us back down.

I think here is a good place for our taiko so I'll lay down a very simple pattern, which I'll also mimic with the bass. Here are both parts (the bass is in red):

Lastly I'll add a melody on the strings and synth, again something very simple. I'll then repeat the whole four bars for an eight bar B section.

Something interesting happened when I added the melody I was hearing in my head, which was unintentional but worked out well. I had intended the harmony change to be from Ab minor to Eb minor, but because of the melody notes we actually ended up with Db minor/Ab to Eb minor. Functionally it still serves my purpose of tension and release, but in a different way than expected.

Repeat the A Section

The B section gave us a chance to rest from the A material, so now when we bring it back it wont be so tiresome. Let's repeat the full A section just one last time as the ending to our piece. All I'm going to do is copy and paste our second A section and place it after the B section. Simple enough, but I'll make an adjustment so it's more of an "ending" by taking out some elements for the last half of the section. I'll mute everything but the synth and harp for the last phrase, which will give the piece more of a sense that it's coming to a close.

Here's the entire piece so far, which I'd say is 90% there:

Listen through for improvements

Now that the basic composition is in place it's time to go back and add pieces of interest and color. That doesn't mean we should just cover the entire thing in percussion and effects, because on it's own the piece generally works. We should just be finding some nice moments to add interest and finishing touches.

To get through this process efficiently I find it helps to listen through the whole piece, taking notes along the way about ideas for what to use. Then the list simply becomes a checklist, which you can quickly move through checking off one item at a time. As I mentioned earlier, you could spend hours repeating even two measures over and over until you drove yourself crazy, instead this technique forces me to get in, get it done, and move on.

Listening through the piece, here's what I find I'd like to add.

  • An interesting sound to pull you in at the start
  • Some sort of evolving pad or spooky sound in the first eight bars
  • Cymbal scrape with the taiko and bass at measure five
  • Shaker in the A section
  • Pad in the second part of the first A section
  • Sound effect before the second A section
  • A sound to pull us into the second A section
  • Pad in the second part of the second A section
  • Sound pulling us into the B section
  • Percussion in the B section
  • Pad in the last phrase of the last A section
  • Smoother tail out for the harp

All of these notes address either filling gaps, adding an element to make one section unique from another, or pulling us into new sections. Now I'll start going down the list

Add interest

Let's start with an interesting sound at the beginning. Interesting does not have to mean unusual or complex, even a strong drum can be an interesting way to lead us off. I'll go for a long and deep bass drum hit. I'll make it nice and deep by EQing off the high end, and long by adding it's own reverb plugin.

Next I'll add a spooky pad to the introduction. I'll choose an underlying sound with a lot of movement, which combined with the vibes ostinato will give our ear more of a challenge to try to keep up. I've loaded up the "Random Wave Groove" preset in ES2, which on it's own is too explicitly synth sounding.

After I cake it in reverb and roll off the low end it will sound more mysterious. I'll have it fade in at the beginning and then back out again into the first A section.

Next we have the cymbal scrape into bar five, easy enough. I'll also add some reverb and delay.

Next I have a note to add shaker to the first A section. I am going to record a live shaker, the imperfections of which will add some subtle nuance (barely noticeable, but it helps). I marked only the A section in the notes, but I'll record it through the whole piece (it will only take two minutes!) so that way I can pick and choose where else I might want it.

In this case I'll have it start in the second part of the introduction. Here's our new intro into the first A section:

For the pad I'll use something very thin and smooth, the Calming preset of EFM1. Mostly just holding down an Eb and Bb, but then echoing the Gb to Eb interval from the melody near the end. I also think I need a little more to fill in the space at the end of the first A section so I'll bring back the pad from the introduction.

I've changed my mind about the sound pulling us into the second A section, I feel like the bass and synth are enough to suggest build and development without hammering the start of each new section over our heads with a big hit. Here's how the second part of our first A section now sounds:

I'll reuse the Calming pad for the second phrase of the A section again, this time just a bit louder. I'll also reuse the cymbal scrape as a lead in to the B section.

Next comes percussion in the B section. I've been keeping the shaker going up to this point, so I'm just going to add one more light element: a ticking hi-hat. I'll also add a cymbal roll coming out of the B section and pulling us into the last A section. Here's the new B:

I've stopped the shaker in the last A section to start setting up the idea that things are dying down.

In the last phrase I'll bring back both our Calming pad and the moving Intro pad, which will give a sense of space, and have them both fade out with the synth at the end.

I'll use a ritard to make the harp feel like it's giving up steam. To do this I'll set a tempo point where I want the rit to begin, measure 46, and where I want it to end, 49.

Next I'll use the tempo editor to create the ritard by dragging the last point down and listening back until it feels right. I'll also adjust the curve to get slower later in the phrase.

Lastly I'll clean up the end of the harp ostinato so the last two pitches end together very softly.

Here is our new ending:

So here's how the final piece looks in the sequencer:

Well there it is, now we'll add some basic mastering and we're done!

What, no mix?

Many of you would probably expect that now that all of the elements are in place it's time to do a mix. Well I think that for the way we've been writing, that's a waste of time. Since every element has been under our control through the entire process we have been mixing them as we worked. If you've made it this far into writing the piece and haven't been mixing as you go along I'd be very surprised, so what exactly do you expect to be mixing at the end?

Our "mix" should consist of a final pass or two just making sure that everything sits nicely and works. I'll tweak a few levels here and there but generally everything will be left alone.


For very quick and dirty mastering I tend to load up a Logic preset, perhaps making subtle adjustments if necessary. For this piece I'm actually using the inappropriately named Final Pop Master Wide and using the default Multipress, Direction Mixer and AdLimit settings. Instead of the Match EQ I'll use a regular Channel EQ and use the analyzer to check that no frequencies are out of control. Often I'll end up rolling off some of the low end and rising a shelf on the high end just a touch.

Of course this is only a fast and functional way to get do some basic "mastering". There are fantastic techniques for doing a serious job and I encourage you to check out the Audiotuts+ Mastering tutorials, but with the focus on outputting music this method works fine.

The end result

So here it is, the final piece. Generally a piece like this will take less than one hour to create, less than two if I'm going to record a bunch of live elements. It's no work of art, but it works and it meets our style and length criteria. This is music to serve a function (perhaps for underscore in a TV show or film), we're not writing it to create an outlet for true self-expression. For that reason it's important to have methods to be able to produce this kind of music quickly and effectively.

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