Crash Course in Digital Audio
summary
Overview of concrete takeaways: Unreal Engine uses real-time decoding to 16-bit assets and renders in 32-bit float, yielding 16-bit -> ~96 dB SQNR and 32-bit mix -> ~190 dB headroom, so quantization noise is usually negligible unless sources are very quiet. Practical tools covered: sound concurrency, sound class/sound mix, submix effects, max channels to limit simultaneous sources and duck/route or compress at the final mix stage. Recommendation: keep source dynamic range high, avoid boosting quiet files, dither when downsampling, and manage polyphony to prevent noise accumulation.
AI-written summary · about
chapters (25)
- 0:00Introduction
- 0:38The Unreal Audio Engine team
- 0:51Join the team
- 2:04Digital audio fundamentals
- 3:23Audio is not a dark art
- 5:28Acoustics
- 6:14Analog recording and reproduction
- 6:50Analog recording: advantages and disadvantages
- 8:29Digital recording and reproduction
- 9:50Numbers in computers: binary
- 12:08Digital as analog
- 12:59Volume perception and decibels
- 14:23Sound pressure level (SPL)
- 15:31Comparison to unity gain
- 17:47Volume perception and frequency
- 20:26Quantization noise
- 22:44Bit-crushing
- 24:41Dithering
- 25:53Bit-depth in Unreal Engine
- 27:57Avoid boosting quiet sounds
- 28:25Avoid audio sausage
- 28:57Think subtractive mixing
- 29:26Use logical mixing vs dynamics processing
- 30:19Dealing with mix and dynamic range in UE4
- 33:37Conclusion and summary
