How to Create More Expressive MIDI Music
A MIDI orchestra isn't a real orchestra. That might not sound very helpful: you know that MIDI is no replacement for the power and humanity of real musicians. But it seems that despite this reality, many people waste their time trying to force their music to sound as "real" as possible by obsessing over the nuance of every single note and beat.
Although these infinite tweaks may eventually yield results, it only takes a handful of simple techniques to address the most common issues that makes MIDI sound so artificial. If using Pareto's 80/20 principle you could argue that 80% of how good your music sounds comes from 20% of the techniques you use, then it only makes sense that we should focus on the 20% that are going to make a real difference.
I've found that the two most important things that can bring your music to life are dynamics and variation. Dynamics are the breath and soul of your music, while variations keep the listener intrigued. A good use of dynamics will make your MIDI sequence sound like less of a machine. A proper balance of variation will keep your listener alert and interested in the music, so that they won't be so wrapped up in whether your English horn sounds synthesized or not.
Make the Most of Dynamics
The number one way to improve a MIDI sequence is to get as much mileage as possible out of dynamics. Dynamics refers to the volume of a note, and can be approached from a micro note by note scale or as an overview of your entire piece. This includes everything from a quiet verse vs. a loud chorus, dramatic crescendos and decrescendos, subtle variety of velocity in a single passage, and accents and articulations.
The most precise way to play with dynamics in your sequence is through note velocity.
The easiest way to demonstrate variations in velocity is with short, sharp sounds. In this example, a short excerpt from Scott Joplin's Magnetic Rag, we'll use pizzicato strings. Here are the first two phrases with no variations in the velocity:
It's not bad, but it's a bit stiff. It might pass, but I think we could make it more musical. By using velocity we can add some subtle life into it. We'll start the first phrase off very quietly and build it up in intensity, accenting that high pluck at the end of the phrase before dropping back down to build once again.
The difference may not be night and day, but there's now a certain element of excitement that wasn't there before. The strings feel like they are sneaking around at first before the high plucks make a bright statement, then back to sneaking once more. If you apply this subtlety across your entire composition you'll find that it will become much more lively and interesting.
Percussion is another section that greatly benefits from adjustments in velocity. MIDI percussion instruments can easily fall victim to the "machine gun effect", where repeated notes of the same sample begin to feel mechanic and abrasive rather than musical. Adjusting velocity can help reduce the machine gun effect, as shown in this simple example of a snare drum passage:
It sounds pretty fake, but all we have to do to inject some life and fun into the part is add accents and dynamics with velocity. Here is the audio of a much more interesting snare part, using the same pattern as before but spicing up the note velocity:
It sounds like a much more convincing snare part and feels more like a real person could be playing it. The same principle applies not only to a constant line like this snare drum, but to subtle variations across all of your percussion parts. If you use the same cymbal sample every 8 bars, the least you can do to change it up is vary the velocity each time it crashes.
Another popular way to use velocity to avoid sounding like a machine is to "humanize". This is an especially useful feature if you are not too strong a keyboard player and usually end up having to draw or write in your musical lines note by note. In Logic Pro you can access the humanize tool via the Piano Roll window, under the Functions menu.
Humanize will randomly adjust the position, velocity, and lengths of any notes you have selected by the amounts you choose (the defaults are 10 for all parameters). Select the notes you want to humanize and choose "Operate Only" to apply the function and see what kind of result you get.
Let's look at our pizzicato section again. To exaggerate the effect I'll send our values to randomize by 25 instead of the less effective 10. It's hard to distinguish, but if you listen carefully you'll notice that the humanized version feels a little looser and more varied. Humanize is another subtle technique that adds just an extra touch of life.
Our straight pizzicato section:
The humanized pizzicato section:
Modulation is a useful tool for automating a MIDI instrument's expressiveness. It is particularly useful for instruments with long notes, allowing you to control the shape of the note and the way it speaks. Modulation is a default parameter on many software instruments today, often used to control volume, filtering, or to crossfade from one sample into another.
To access modulation in Logic Pro: open a Piano Roll window, click the Hyper Draw button in the lower left and then click the small triangle to choose the controller type. Select modulation and we're good to go.
Let's take a look at a basic but common use of modulation. Using a long strings patch, here are a few chords played with no adjustment to modulation:
For the simplest demonstration we'll take modulation from 0 to 127 over the first two bars, and then back from 127 to 0 over the last two bars. The effect is a crescendo up to the G major and decrescendo back down. On this particular instrument (Sonic Implants Full Strings) modulation is set to crossfade samples, so while we're starting at a pianissimo sample, modulation will fade us up to a fortissimo sample.
It's more expressive, but still a little weird sounding. Let's play with the modulation even more to make it more interesting.
This time we've used curves to make the changes much more dramatic and exciting. The strings now feel like they're rising up into the G major chord and then dropping off suddenly, before tapering out smoothly.
Volume & Expression
Perhaps the most obvious way to control dynamics is by automating volume. Although modulation is effective for controlling the sound of an instrument, volume is more useful as an overall control of loudness. I tend to use volume not only to balance one instrument against others in a mix, but also to control more global shifts such as a fade in or out. Used in conjunction with modulation, it can be a very expressive tool.
Using our long strings passage as an example, I'll automate volume to get even more dynamic breadth.
Because the modulation is controlling most of what I want out of the sound, I'm using volume more as a broad stroke to give it that extra push. Another similar tool is the Expression controller, however I tend not to use it. After running into many instruments that are not set up to work with Expression, I've found it easier to rely on volume as a tool that will work on any instrument.
Keep it Interesting & Varied
As I discussed earlier when talking about velocity, the fakeness of MIDI is most apparent when notes repeat. Although velocity is one way to address this problem, you can help keep things interesting by varying all sorts of other elements such as pitch or color.
Consider this example of a string ostinato. Playing the same note on the same sample over and over, it's about as ugly as it can get. Here we have the "machine gun effect" of feeling like we're under constant attack by a stuck machine.
This is MIDI at its worst! Right away we can begin to address this issue by varying the velocity to make each note feel at least a touch different. I'll have the strings crescendo and decrescendo for a rising and falling effect.
Now let's take it a step further and vary the pitch. Here I have the line alternate between a D and the A below it, which not only frees us from the dreaded machine gun, but it also give the line more of a sense of motion.
Now I'll vary the pitch even more by adding a climbing and falling D E F E line in the top part. This makes the string part a lot more interesting to listen to, but it's still not too distracting or flashy for whatever else you might want to put over it. Also notice the effect of varying the pitch so often: the less you hear a MIDI note repeated, the less your ear is able to associate the repeat as identical to the one before it.
Lastly let's add an additional color. We'll keep the notes and rhythms exactly the same, but by layering a contrasting color it will keep our ear distracted and give a further sense of richness. I'll use a vibraphone as the second color, as the mellow and dull attack is quite unique from the sharp and bright strings. The result is a more complex sound, which helps distract our attention from what would otherwise be very exposed MIDI strings.
Another way that you can keep a repeated figure interesting and varied is by alternating some specific aspect of it, such as changing the register or instrument it's played on. Let's take a look at another example of an ostinato figure that repeats.
In this example we already have a somewhat complex figure, with strings, vibes, and a snare. We're using modulation and volume to give the strings and snare a sense of swell, and velocity to control the dynamics of the vibes. Overall we already have a fairly expressive two measure pattern here. The problem is, by the third time we hear it we're already starting to get bored. With some very minor changes we can make this a lot more interesting and musical.
I'm only going to make two changes. Every other bar I'll have the strings play three octaves higher and I'll take out the snare. It doesn't sound like much, but listen to how much more interesting this is:
There are really no new notes or ideas here at all, just a variation on what already exists. But we've managed to make it more interesting, and successfully turned eight seconds of music into sixteen. Film composers: remember this technique the next time you need to effectively vamp over a scene!
Just to drive home the point even more, I'll make one minor change for the next four bars. I'll bring everything up a minor third. That's the only difference, but now we've doubled the length of our music again!
A single musical idea has an infinite potential for variation (the opening four notes of Beethoven's 5th come to mind). With just one or two changes your ideas can evolve and become much more interesting.
Incorporate Live Elements
I'll admit that talking about using live musicians in an article about MIDI is a bit of a cop out, though it's something absolutely worth considering. This is one of those tips that is often easier said than done, but even the slightest touch of a live instrument can add animation to your sequence. The easiest way to do this yourself is with percussion. I always have a tambourine and shaker on hand, and if there's ever a section in a track I'm working on with a groove or a lot of forward moving rhythm I'll add a subtle layer underneath everything with one of these instruments. The fact that my performance can never be perfect, with slight difference throughout with volume and timing, is exactly what adds that human touch that is more felt than heard.
Most likely the majority of you already play guitar or bass, and if you don't than it is time to seriously consider learning the basics and becoming at least proficient enough to play simple parts. MIDI guitar is one of the ugliest things out there, and being able to play your own parts can make the experience of writing your track more fun but also adds life. MIDI bass is often not so bad or noticeable, but if you have a chance to play your own parts it's again those subtle and unavoidable human errors that can make a big difference in how fresh your music sounds.
More difficult to accomplish, but with equally great benefit, is to find musicians and singers to perform on your tracks. Even a live flute solo with MIDI background can sound great, with the expressive live featured instrument drawing the majority of the listener's attention. Also extremely helpful to adding warmth to a cold MIDI track is to sweeten your synth strings with live string players. One or two takes of a live violin blended in with a MIDI string section can make the whole piece feel more tangible and real.
MIDI is not a substitute for live musicians, and doing whatever you can to incorporate as many real players as possible will make a huge difference in the overall life of your piece.
The final and arguably most important thing you can do is make sure that you don't lose perspective. After listening to the same sequence for hours on end, your exhausted ears and mind could probably convince you that just about anything sounded good. Give your ears a rest and step away from your song for a while so that when you come back to it, you'll have a fresh listen and a more realistic impression of what your piece really sounds like.
It's very easy to convince yourself something sounds good because you get caught up in what it's "supposed" to sound like. In your head you imagine that the strings are full and lush and your imagination can quickly begin to compensate for things that are missing in the real music. Make sure you keep yourself detached enough to always be aware of what your MIDI sequence actually sounds like. It can help to listen to some of your favorite recordings in a similar style, back-to-back with your piece.
If you apply these basic ideas to your sequences, you can begin to take your compositions from sounding like synthesized muzak to vibrant and expressive music.