iDevGames

Staff note: the original tutorial that was sent in was spread over 16 html files. The html was in pretty terrible shape. I removed it all, and converted to Textile but the tutorial still needs better flow and layout. Do your best to make each step consistent. Re-write passages for clarity as well. Thanks!

Castles Music Sound FX Walkthrough

Resources/0.gif

alt=“Basic Sound Effect Design, March 2003, Castles Music Productions

Resources/0a.gif

What was supposed to be a simple “how-to” on Sound Design has turned into this article! You can blame all the indie game developers I have ever worked with for inspiring what you are reading.

This article is in two parts.

Part 1 — Things to consider before designing sound.

Part 2 — An example of creating an Explosion sound effect.

Note: I’m using Macintosh software and the walkthrough uses some shareware mac software. You can replicate most of the steps in your favourite PC editor like Goldwave, or SoundForge.

Sound FX Walkthrough 01

Resources/0b.gif

Part 1 — Preliminaries

Resources/0c.gif

Resources/0d.gif

When you are designing the concept for your game, spend a little time working out how you want it to sound. Is it going to be a full-on arcade assault with bleeps, bloops and explosions all over the place. Or are you going for a tense sparse atmospheric feel?

Some things to consider when you are thinking about sound.

• Type and Number of Sounds
• Space requirements or restrictions

• Formats

Sound FX Walkthrough 02

Resources/0b.gif

alt=“Part 1 — Preliminaries

Resources/0e.gif

Resources/0f.gif

It would be useful to define some different types of sound effects: Ambience, Normal Effects, Special Effects, and Interface Effects.

• Ambience: Sounds that occur in the environment of the game (also called Environmental sounds.) These are often loops (constantly playing in the background) or sometimes one-shot (played only once at random intervals.)

They can really add to the vibe of your game—mad screams from inmates can be heard down the corridors of the insane asylum, birds tweeting, leaves rustling in the wind, planes flying overhead, cars traveling on the streets.

One of the coolest environmental sounds I’ve heard recently was in “Medal of Honor: Frontline.” In one of the last missions you must fight your way through a steel foundry. The sound of the hot metal pouring into the moulds is amazing. It totally freaked me out when I first played the game because you can hear the sound coming from adjacent rooms — and it sounds like some huge monster!

• Normal Effects: The stuff that happens in-game. If you were doing a card playing game, the sound of the cards being dealt and flipped over by the player would be a Normal Effect.
• Special Effects: The big payoff or surprise sounds that add spice and reward to a game. In Blastorama the explosions are made as big sounding stereo files which reward the player for blasting the hell out of the level they’re playing. In BaseGolf I did a “Tadaaa” fanfare for a hole-in-one shot.

• Interface Effects: Sounds used in menus, for selection of items etc.

You’ll probably be spending most of your time getting the Normal and Special Effect sounds just right.

Sound FX Walkthrough 03

Resources/0b.gif

alt=“Part 1 — Preliminaries

Resources/0e.gif

Resources/0g.gif

What actions, events or locations need particular sounds? Selecting options and menus, key in-game events, repetitive events (like firing a gun, or hitting a baseball,) player footsteps, monsters, ambience — these can all play a part.

Resources/0h.gif

Since some of your normal effects have the potential to be repeated hundreds of times, it might pay to consider doing multiple versions of some sounds. Alternatively you can program small random pitch and volume changes to occur in-game for particular sounds. Either way, it’s good to get a rough idea as to how many sounds you will want because that will affect other areas of the game not least of which is the file size consideration for downloading.

Sound FX Walkthrough 04

Resources/0b.gif

alt=“Part 1 — Preliminaries

Resources/0i.gif

Space or file size restrictions play an important part in choosing how many sounds and the quality of sounds you use. Space restrictions for downloadable games. If you make games for download it seems 5MB is about the ‘magic’ file size for the total game. Usually people are using compressed formats to reduce audio file size.

Resources/0j.gif

Typically when a game uses uncompressed files they are 22kHz, 16-bit, Mono. Which type of compression used depends on the development and delivery platform. MP3 and OGG are promising, Microsoft ADPCM is ok, but all of these compressed formats have overheads in terms of the power required to decompress them on the fly and I have experienced problems with looping compressed sounds. It’s a good idea to try out a few formats and see which suits your style, audio engine, and project.

Sound FX Walkthrough 05

Resources/0k.gif

alt=“Part 1 — Sound Design Process

Resources/0l.gif

Resources/0m.gif

There are several ways to get beginning sounds for effects. From recordings you’ve done yourself, from sound libraries, from sound manipulation software on your computer, or from the web.

Note: I try to steer away from using sounds from the web as they are often ‘shonky’ ie. Stolen from a commercial sound library, from a movie, or some other copyrighted source. There are some great sites with free sounds however (eg: Flashkit) you just have to finds them. I generally start from a sound library sound and/or a sound I’ve recorded myself.

Resources/0n.gif

Sample rates and Bit rates.

You can think of sample rates and bit rates a bit like the quality of a JPEG picture. With a JPEG, the lower the quality (higher the compression) the worse it looks. With audio files, the lower the bit/sample rates the worse it sounds. [Note: sometimes low bit-rate sounds can work really well, like in the Matrix movie for example]

The key to getting a good image (or sound) is to start at a higher resolution/quality, edit your files at this resolution and then convert your files from to lower quality from there.I generally use 44.1kHz, 16 bit for my high-quality files (lately I’m using 48kHz, 24bit.).

A lot of the audio files from the internet are lower quality like 22kHz, 16 Bit or even 11kHz, 8bit. I’m not going to cover sample rates and bit rates in this article but needless to say, starting from highest quality is always best. Gather as many sounds as you think you might need to create a particular effect.

Sound FX Walkthrough 06

Resources/0k.gif

alt=“Part 1 — Sound Design Process

The general procedure I use for creating effects is pretty simple, and I’ll cover it more when I run through an example later on.

• Load the sound into the audio editor
• Edit the sounds with DSP functions, trim the file etc
• Layer sounds together for bigger, more interesting effects.

• Experiment!

Resources/0p.gif

Resources/0q.gif

• MP3 — iTunes. The most convenient method of converting to MP3.
• OGG — OGGDrop, Audacity, Amadeus all can do this format.
• WAV — most tools allow you to save as a WAV file

• AIF — any MAC audio editor can do this format

Some other tools that would be useful for audio conversion:

• SoundApp — I use this program a lot. It isn’t the best quality but it can convert between many formats and is a good way to audition lots of files.
• Sound Hack — I have no experience with it but it looks pretty good.

• Amadeus II — I love this program, lots of good features and great denoising, support for VST effects and it doesn’t cost the earth.

Sound FX Walkthrough 07

Resources/0r.gif

alt=“Part 1 — Sound Design Process

Resources/0s.gif

Once you start getting more than 20 sound files, it is a good idea to keep track of them. There is a document on the iDevGames.com site by Yogic Flyer which outlines a good standard for art asset file naming conventions:

XXX-YYY-RRRxRRR.ZZZ

Where XXX is the prefix, YYY is the description, RRRxRRR are the dimensions, and ZZZ is the suffix (extension.)

To expand on that for audio you could use:

LLL_XXX_YYYRRR.ZZZ

For example: a02_sfx_bubbles002.aif

• LLL is information specific to your game to help you identify where this audio belongs, in which level. For example: A01 — for Mission A, Level 1. It can also allow you to make the destinction between interface and game sounds (e.g.: I00 — for Interface sounds.)
• XXX is the identifier for the type of audio: (E.g. mus = Music Track, sfx = Sound Effect )
• YYY is the description of the audio file
• RRR is any particular extra info (e.g. Sample Rate, Version Number)

• ZZZ is the suffix.

Our example again: a02_sfx_bubbles002.aif

From the name we can tell that this item is used in Mission A, Level 01. It is a sound effect, it is a bubble sound effect and it’s version two. Finally it is an AIFF file.

Sound FX Walkthrough 08

Resources/0t.gif

alt=“Part 2 — Sound Design Example

Resources/0u.gif

Since I don’t have access to explosives I can’t really record my own real explosion sound. Most ‘real’ sounds don’t really sound big enough anyway so I like to layer sounds to create that ‘big’ sound. I’m using as the basis of the explosion a sound effect called “Classic Explosion” which is from the “Ear Shot sound effect archive” which I own.

ExplodeClassic:

When not using Sound Library stuff as a beginning I might also use original recordings from my MiniDisc, or sounds created from computer-based synth software. You could just use this sound by itself but that would be cheating, not to mention lazy….and lazy cheaters go to hell. So to avoid that I always try to give a base sound effect a bit of character that is my very own. This is where we begin the process of creating another layer or several layers to create the perfect sound. The original Classic Explosion sound has a sort of high-pitched shock wave sound that I really like so I’m going to try and emphasise that with another sound. I’ll start with a sound called “Mega Distort Battle” that I created from a PLUGGO plug-in called Feedback Network.

[PLUGGO is a set of over 100 Mac-only VST plug-ins for $100. Available from www.cycling74.com. There are other free plug-ins that can do this sort of thing like THONK which you can do a search for on Google if you want to find it.]

MegaDistort:

So remember that I’m editing this sound because I intend to layer it with the other explosion sound so first I need to prepare the bits I want to keep and get the file ready for work.

Sound FX Walkthrough 09

Resources/0t.gif

alt=“Part 2 — Sound Design Example

Resources/0v.gif

I’ve chosen to keep the first part of the sound because there is a nice high-pitched sort of sound going on there.

• In Amadeus select the first 5 seconds of the sound and use Edit — Crop to remove the rest of the file, leaving behind the first 5 seconds.

Resources/0w.gif

I want to fade in the beginning and fade out the end so that it sounds a bit smoother.

• Select from around 2 seconds to the end of the file and choose Effect — Fade Out.
• Select from the beginning of the file to around 1.5 seconds and apply Effect — Fade In

• We now have a nice chunk of audio to play with.

Resources/picstep0102.jpeg

alt=“PicStep0102

TIP: Save incremental backups of your audio file even if your audio editor supports multiple undo. You never know when you’ll want to go back to an earlier version.

Sound FX Walkthrough 10

Resources/0t.gif

alt=“Part 2 — Sound Design Example

I found a free plug-in on the net called MadShifta that is a dirty little pitch-shifting tool. I’m going to try pitch shifting the file to see if that makes it more interesting.

• Select the whole file (which makes sure the plug-in is acting on the whole file and not just a little portion of it.)
• Apply Effect — VST Plug-ins — MadShifta with the settings shown.

• The results sound nice.

Pic_Step03_Madshifta.jpg

Resources/picstep03madshif.jpeg

alt=“PicStep03Madshifta

Now I want to home in on the core sound a bit more.

• Select from around four seconds to the end of the file, use Edit — Clear to remove this part.

• Apply Effects — Fade Out to the last second or so of the file.

Sound FX Walkthrough 11

Resources/0t.gif

Part 2 — Sound Design Example

Resources/0z.gif

Lets make the volume of the file a bit louder

• use Effects — Normalize with a setting of 98%. This increases the ‘loudness’ of the file.

Pic_Step05_ShowingFile.jpg

“Resources/picstep05showing.jpeg

alt=“PicStep05ShowingFile

Resources/0-1.gif

To add some movement

• apply Effects — VST — mda Auto Pan which moves the sound between the left and right speakers.

MDA Auto Pan is a free VST effect that comes with Amadeus.

The resulting file is pretty cool.

Resources/picstep06showing.jpeg”

alt=“PicStep06ShowingFile

Resources/picstep0506autop.jpeg

alt=“Click here to see the AutoPan settings for Step 6”

Sound FX Walkthrough 12

Resources/0t.gif

alt=“Part 2 — Sound Design Example

Resources/0-2.gif

The sound needs a bit of a trim so we’ll trim the beginning and end off the Mega Distort file.

• Select from the beginning to around 0.5 seconds. Use Edit — Clear to get rid of that part. Now select from around 2.0 seconds till the end and use Effects — Generate Silence. This will clear the end of the fade but leave silence for us to add a little more spice to the sound.
• Fade out from about 1 seconds till a little after 2 seconds.

• Use Effects — VST — mda ThroughZero with the settings shown to get a choppy phased sort of sound.

Resources/picstep07thruzer.jpeg

alt=“PicStep07ThruZero

Resources/0-3.gif

That sounds good, but now it’s a little dry. So we are going to use a reverb to create a more open washy sound.

• Use Effects — VST — FreeVerb with the settings I have used. This produces a nice open wash.

Resources/picstep08freever.jpeg

alt=“PicStep08FreeVerb

Sound FX Walkthrough 13

Resources/0t.gif

alt=“Part 2 — Sound Design Example

Resources/0-4.gif

• First save a copy of the file as it is as another name- we’ll come back to it in step 10.
• Now to accentuate the end of the sound, and to make sure the sound doesn’t get in the way at the beginning of the explosion, lets Fade in from 0 to around 0.6 seconds. Do the Fade in on the same selection again twice more to make sure there is clear space for the other sound later on.
• Select from 1.8 seconds till the end and use Edit — Clear. Fade Out from 1 second to the end of the file.

• Now reduce the volume of the file again by using Effects — Normalize with a setting of 20-30%

Resources/0-5.gif

Still more is needed I think.

• Open the copy you saved in Step 9.
• Apply Effects — MadShifta with the settings shown.
• Apply the Effects — VST — DFX Skidder with the settings shown below. This produces a neat grungy skipping sort of a sound.
• Clear from around 2.4 seconds to the end.
• Fade in from the beginning to1 seconds.
• Fade out from 1.2 secs to end
• Normalize to 40%

• Save this file.

Resources/picstep10madshif.jpeg

alt=“PicStep10Madshifta

Resources/picstep10askidde.jpeg

alt=“PicStep10aSkidder

Sound FX Walkthrough 14

Resources/0t.gif

alt=“Part 2 — Sound Design Example

Resources/0-6.gif

Now to layer the sounds together. Make sure the three sounds we have created are now open.

• Edit — Select All of the file from step 9 and then click on the Classic Explode window. Now Select All there and choose Edit — Paste Over (See picture below.) The copied sound will be mixed in with the destination.

• Do the same with the file from Step 10 and have a listen to your results.

Resources/picstep11pasteov.jpeg

alt=“PicStep11PasteOver

Sound FX Walkthrough 16

Resources/0-8.gif

alt=“Download this Walkthrough

Resources/0-9.gif

Feel free to download this walkthrough. It’s compressed into an archive with a PDF document and the associated MP3 files in a folder for you to play with—enjoy.

CMP Sound FX Tutorial

Sound FX Walkthrough 15

Resources/0t.gi

alt=“Part 2 — Sound Design Example

Resources/0-7.gif

Not a bad effort really, a great original effect ready for exporting into our favorite format.

ExplodeClassic (Original File) :

New Explode (Our New File) :

And with a little tweaking of a few parameters here and there, I came up with some variations:

Variation 1 :

Variation 2 :

As you have seen, half of the process is experimentation, trying stuff out and seeing how it sounds. To sumarise the steps I take:

• Gather raw sounds
• Edit, experiment, twist and generally muck around with the files until you get something you like

• Layer sounds together to get a more interesting effect.

That’s it really, get to work!

“Resources/audio03b.gif

alt=“Audio03b

About the Author:

Simon ‘Himiona’ Castles heads Castles Music Productions, New Zealand’s premiere audio production house for computer games. For a full profile visit the Castles Music website at: http://www.castlesmusic.co.nz

basic,sound,effect,design