Women in Games Boston Feb. 2018 Meeting
Getting Started with Audio for Games
About this Talk
This talk was broken into two parts: the first was about how to approach doing audio for a game and important tools, and the second was a live demonstration of sound design and composition techniques in Audacity and Garageband. It was intended for people that have no prior experience with audio, and was aimed towards giving them the techniques and resources they need (without spending a million dollars) to go home and get started right away. The first half of the presentation was done entirely with slides, which you can download below. I've left my notes in the slides - they elaborate a bit more on some of the bullet points. There's a separate link for downloading the example projects that I used, and I'll go into a bit more detail here about what to be listening for. None of the explanations of any of the effects below go into really technical details, but should give you enough knowledge to get started and use the effect with intention.
01 - Audio Editing
A lot of good sound design begins with good audio editing. Whether you're using a sound from a library or something you've recorded on your own, at some point you're going to need to change the length of of an audio file. Doing this in Audacity is easy enough - you just need to select the I-beam tool, click and drag over the section of the audio file that you'd like remove, and then hit delete.
What you'll notice when you play back the file, however, is that it pops at the start and end! If we zoom in to the file by using the magnifying glass, we can see the reason why:
When our audio doesn't start from 0 (the black line in the middle of each track), we get a pop. There are two easy ways to fix this. The first thing we can do is to always make edits at a zero-crossing (the point where the waveform intersects with the black line), seen below.
The other option is to add a fade-in. To do this, start by zooming in extremely close to the beginning of the waveform. Next, click and drag to select the very beginning of the waveform. The fade-in will happen in the portion of the file that we've selected.
To actually create the fade, we'll next need to go up to the top menu and select Effects > Fade In (while the portion of the waveform that we want to have the fade happen during is still highlighted).
Because we've zoomed in so much and are working with such a small amount of time, you shouldn't be able to hear the fade in once you play the file back. Instead, the click should be gone and the rest of the file should sound the same as before.
02 - Looping
In this Audacity project, you'll see two tracks. Both contain the same loop of the sound of rain falling, but the bottom is shorter than the top one. To listen to these tracks loop, double-click the waveform, and hold down the shift key before pressing play (the play button image will change).
There are two big things to notice while listening to these:
It's much harder to tell when the longer track loops back to the beginning. In general, aim to make your ambiences (background sounds like birds/insects when outdoors, and heaters/air vents when indoors) longer rather than shorter.
There are no parts of either loop that really stand out. Since we're very good at detecting patterns, we'll very quickly pick up on anything that stands out and notice that it's playing over and over again, especially if the loop is very short. So, for example, if there was some thunder that happened in the middle of our rain loop but nowhere else, we would be able to identify the loop when we hear the exact same thunder sound over and over. Making sure that no huge changes in loudness or timbre will help make the loop less noticeable.
03 - Layering
One of the most commonly used techniques in sound design is layering. A lot of the sounds you hear in games are actually combinations of multiple different sources. In this Audacity project, the top track is a sound I made for an ice spell. Below is a picture of what it looked like creating the sound in another DAW called Cubase.
The big point here is to remember that some of the most interesting sounds you can make are actually done by combining others! Time and experimentation will help you come up with a palette of go-to sounds that will help you speed up your process.
As a comparison, the lower track in the Audacity project is the same ice spell, but made without the layers! The layered one is definitely cooler and less ambiguous than the one without.
04 - Pitch Shifting
Pitch shifting is one of the easiest ways to get a lot of variation from one source very quickly. It means changing our recording so that it sounds higher or lower than the original, and may or may not make the sound file longer or shorter than the original. I've found it to be particularly useful when creating creature sounds, especially when the length of the file changes, and when using the human voice or animal sounds as a base.
Audacity makes this very easy.
05 - Reverb
05 - Reverb
Reverb is an effect that places a sound in a space. For example, we frequently use this in music recordings to make the instruments sound like they're playing in a large hall instead the small studio they were originally recorded in. With sound design, reverb is helpful for making something sound like it's in an indoor or enclosed space such as a cavern, or for making impacts and spells sound larger and more impressive.
Audacity includes a reverb plug-in, and I encourage you to use the presets when first starting out. Presets are a predetermined group of settings that let you quickly arrive at a sound. For example, reverb presets let you choose a "room", and changes the settings to sound like the type of room you selected. We won't go over each individual slider in the plug-in during this tutorial, but once you've gotten used the presets and what reverb can do for you, the next step would be to change one slider at a time and see if you can hear the difference.
To add reverb to the sound in the included Audacity project, double-click the sound file to highlight the entire thing. Once you've highlighted it, go up to Effects > Reverb.
Once you've clicked on Reverb, the following window should appear. To access the presets, click on Manage to bring up the menu.
If you hover over Factory Presets, the list of presets available appears under Defaults. Clicking on anything in this list will bring up the associated settings. Click OK after clicking on the preset you want to use to apply it to the highlighted selection.