One decision you will need to make during your project development is the type of audio you would like in your final product.


Lossless vs Lossy

One concept of audio is the difference between a lossless and a lossy format.

Lossless stores data uncompressed, storing all of the frequencies in the audio. The file is significantly larger as a result. A popular choice is WAVeform (.wav).

Lossy compresses the audio, which deletes top and bottom frequencies depending on the bit rate. The file size is significantly smaller as a result. A well known format is MP3.

To maximize the audio quality of your project, you should consider keeping the original and converting a copy based on your needs. Regardless of how much you sacrifice file size over quality, by keeping the original, you can re-convert later if desired.

For some runtimes, Fusion may convert the file to a different format. As with the case with HTML5, as different web browsers support different sound files.

Format Comparison

File Extension Format Type Supported by Fusion? Free to Use?
.wav Waveform Audio File Format (WAVE) Lossless Yes Yes - No license
.ogg Ogg Vorbis Lossy Yes Yes - Free software
.aif / .aiff Audio Interchange File Format Lossless Yes Yes - No license
.mod / .it / .s3m / .xm Amiga Music Module File Sequencer Yes Yes - No license
.mp3 MPEG-2 Audio Layer III Lossy Yes Yes - Licensing Ended
.mid / .rmi MIDI Sequencer Files Sequencer Partial - Windows EXE only Yes - No license
.wma Windows Media Audio Lossy Partial - DirectShow only No - Licensed

See the Sound Object for compatibility across exporters.

A sequencer only stores musical notes, instruments or both. This type of format does not contain any streams and is played “on the fly”.

Choosing the Compression Ratio

If you opt for a lossy format, choosing the amount of compression is likely to vary depending on your music and sounds.

Bit Rate Label
64 kbps Poor Quality
128 kbps Good Quality
160 kbps Better Quality
192 kbps High Quality
256 kbps Very High Quality
320 kbps Excellent Quality

Positional Audio

If you are using positional audio (for sound effects), you will also want to convert your sounds to mono to half the file size and prevent interference on panned channels.

MP3 vs OGG Vorbis

File Size

The Ogg Vorbis format is superior is MP3 as it can store more frequencies (thus, higher bit rates) at a smaller file size to that of MP3.

Comparing a 30 second 440Hz sine wave:

Bit rate MP3 Ogg Vorbis Difference
64 kbps 201.5 kB 45.9 kB +22%
128 kbps 319.6 kB 48.8 kB +15%
192 kbps 327.0 kB 54.5 kB +16%
256 kbps 347.4 kB 58.5 kB +16%
320 kbps 369.5 kB 60.8 kB +15%

For reference, a 16-bit signed PCM WAV and AIFF file would be 2.6 MB.


Ogg Vorbis is natively supported by Fusion, and is compatible across all runtimes whereas MP3 is available for selected exporters (such as HTML5).