If you are like me, you dread adding sound to your game. Not because you don’t want to but because making sound effects is difficult. Most people don’t know where to start or even how to get them into their game. In this post I will cover some techniques I use to make sound effects for my own games while covering the basics of some free open source tools I rely on.
I know how daunting making sound effects for you game can be. To help get you started, I have supplied my own library of sound effects which I continuously reuse in all of my games. All of these sound effects were created by a great app call Bfxr. Bfxr is a Flash app you can use in the browser or download and run via AIR which generates 8-bit sound effects for your games. Let’s take a look at its options.
At first you may feel a little overwhelmed by all of the settings but Bfxr is really easy to use. Most of the time I simply start with one of the presets such as Pickup/Coin, Laser/Shoot, Explosion, etc. If these don’t get me want I am looking for, I tend to use Randomize and cycle thought a few different randomly generated sounds until I find something I like.
As you continue to make new sound effects, each one is saved for you under the sound template buttons:
You can delete any sound you don’t like by clicking on the X button. You can also chose to export each song individually by pressing the Export Wav sound. Also, you can save out a .sfx file which contains all the raw data for the sound effects created so you can go back later and modify them.
The last thing you can play around with are the individual values for each sound effect:
To be honest I don’t know what most of these do well enough to explain but I tend to just play around with them and see what happens. Bfxr is really forgiving as long as you remember to save and/or duplicate the sounds you continue messing around with. I find the best technique is to simply get a sound effect I like, duplicate it, and spend some time messing with its properties until I get something I am happy with. After that I change its name accordingly and save out the .wav as well as the .sfx file so I can come back to it later.
Now that you have sound effects to work with you are probably going to need a way of editing them, or at the very least you will need a way to convert the .wav files into something your game can use. In order to do this you are going to need an audio editor. There are a lot of options out there but I use a free app called Audacity which you can check out here. While Audacity may not be the best looking audio editor out there, it gets the job done. Here is what you see when you load up a sound file.
Audacity is a standard sound editor, you can trim an audio clip down, modify the sound levels and also test how an audio clip loops. The latter is important for music and if you hold down shift when clicking play the sound will continuously loop. You can also load up multiple sound effects at once to help with batch exporting like so:
Simply select them all and hit export. From there you have many options to save the files out.
This is incredibly helpful when it comes to developing HTML5 games where you need to produce multiple formats of a single sound file such as .mp3 and .ogg.
As you can see I don’t have a very high tech setup for creating sound effects for my games. Sound is not one of my specialties so I tend to just do the bare minimum to get by. I think Super Jetroid was my first foray into layering sounds and doing more dynamic things like fading up a loop when you run low on air or are about to die. Obviously these techniques work really well if you are doing retro looking games but a quick search on the web will yield endless supplies of open source and royalty free sounds. Also, don’t forget to go through and feel free to use them in your own game.