sound effects

Sound effects

Overview

Adding or changing sound effects in Open Surge is pretty simple and straightforward. They are stored in the samples/ folder. If you're not an audio expert, you may consider using free programs such as sfxr to automatically generate sound effects for your game. OpenGameArt also has plenty of free sounds that you can use and remix.

Format

You may use .WAV and .OGG formats. Free audio editors, such as Audacity, are able to provide you with options to control the sampling frequency and bit depth of your sound effects. What do these mean?

Sampling Frequency

Suppose you're watching a road, and every 5 seconds you had to register if there were cars passing, or if nothing passed. That would probably make you lose track of most of the cars, so if you increased the FREQUENCY of your annotation, you'd get closer to how many cars pass by in reality.

In audio, frequency is expressed in Hertz (Hz). One Hertz is the same as "once per second". A sampling frequency of 44.1KHz means 44100 times per second. That's why recordings with higher Hertz rates sound better, because the human ear takes less guesses to fill in the gaps.

Bit Depth

A common question when mentioning 16-bit audio is "Is that the equivalent to audio from a 16-bit console?" The answer is "no". Bit depth in audio specifies how many volume bits the wave can use.

A 1-bit wave would translate into "Sound" (1) or "No sound" (0), Background noise would either become silence, or part of the full sound, since there are no intermediates.

A sound with higher bit depth enables more volume levels. A 16-bit sound has up to 65636 levels of volume, but costs more disk space.

Recommended formats

For .WAV samples:

Average quality / Low disk space

• 22050 Hz 8bit
• 16000 Hz 8bit

Good quality / A bit more space

• 32000 Hz 8bit
• 22050 Hz 16bit

Even more quality / Even more space

• 44100 Hz 16bit

.OGG compresses audio pretty well, so if you prefer .OGG samples, these formats can be kept with minimal space usage.