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Waveform Audio File Format is an audio format with a .wav file extension, used by all of Valve's engines. It is required for lipsynced dialogue and looped sounds without a custom audio backend.

GoldSrc GoldSrc supports uncompressed 8-bit or 16-bit PCM, although lip-synched audio must be 8-bit. It supports sample rates of 11025 Hz or 22050 Hz; other sample rates can sometimes be used, but they will be resampled to 22050 Hz before playback (unless MetaAudio is used, which also increase audio quality).

Source Source supports uncompressed 8-bit and 16-bit PCM, as well as compressed 4-bit Microsoft ADPCM. It supports sample rates at 11025 Hz, 22050 Hz, and 44100 Hz; files at other sample rates, such as 32000 Hz and 48000 Hz, will not play.

Icon-Bug.pngBug:Files using the extended Broadcast Wave Format (BWF) have weird behavior in Source, and should be converted to regular WAV using FFMpeg or Audacity before use in-game. Some audio editors export as BWF automatically, such as Pro Tools and Logic Pro, and do not provide an option to export a standard WAV.
Warning.pngWarning:Although the WAV format specifications permit up to 32 channels in a single file, and Source supports surround sound, Source does not support WAV files with more than 2 channels!
Confirm.pngConfirm: What about Source 2 Source 2? It definitely supports 16-bit 44.1 KHz WAVs (mono and stereo), but does it support the other formats that Source and GoldSrc support?
It supposedly supports arbitrary sample rates for MP3s; is this the case for WAVs as well?

Bit rates

WAV files have a consistent bitrate depending upon their sample rate, bit depth, and channel count. The following tables indicate what bitrates files will be at supported sample rates.

Tip.pngTip:Bitrate = Sample Rate * Bit Depth * Channel Count

Mono sounds (1 channel)

Sample Rate 16-bit PCM 8-bit PCM 4-bit ADPCM Quality
11025 Hz 176.4 kbps 88.2 kbps 44.1 kbps AM radio; used by most Half-Life sound effects
22050 Hz 352.8 kbps 176.4 kbps 88.2 kbps Max sample rate of GoldSrc sound effects
44100 Hz 705.6 kbps 352.8 kbps 176.4 kbps CD quality

Stereo sounds (2 channels) (not in GoldSrc)

Sample Rate 16-bit PCM 8-bit PCM 4-bit ADPCM Quality
11025 Hz 352.8 kbps 176.4 kbps 88.2 kbps AM radio
22050 Hz 705.6 kbps 352.8 kbps 176.4 kbps
44100 Hz 1411.2 kbps 705.6 kbps 352.8 kbps CD quality
Tip.pngTip:(only in SourceSource 2) If lower file sizes are desired, MP3 files can also be used in some situations; see Compression (Source 1)#Audio Compression for comparisons.

See also

External links