Audio Metering for Game Developers

Jason Cobb Game Audio Design GL33k The Sound Department – Austin

Game Audio Metering Room Survey

Who uses audio meters to examine game sound output levels on a regular basis?

Game Audio Metering Room Survey Who uses audio meters to examine game sound output levels on a regular basis? Who considered metering but has not set it up?

Game Audio Metering Room Survey Who uses audio meters to examine game sound output levels on a regular basis? Who considered metering but has not set it up? Who is unfamiliar with audio metering?

Audio Meters are a Fixed Frame of Reference Playback systems color sound output Listening environments are different Amplification is variable Listener fatigue changes perception of loudness Individuals hear things differently

Audio Meters Provide Useful Information Warnings for loudness issues and signal clipping Visualization of levels and spectral response Practical metrics for discussion of mix changes and audio modulation Coordinate sound teams and inform other disciplines

Game Audio Metering Potential Users Audio Directors and Mix Engineers Established tools for audio production Stay on top of the mix Loudness consistency across game levels implemented by a team

Game Audio Metering Potential Users Audio Directors and Mix Engineers Established tools for audio production Stay on top of the mix Loudness consistency across game levels implemented by a team Audio Programmers and Designers Check reference of sounds implemented Log audible result of audio modulations Debug audio engine errors

Game Audio Metering Potential Users Quality Assurance Identify cases of over-modulation Gain insight into audio bugs Verify adherence to technical standards

Game Audio Metering Potential Users Quality Assurance Identify cases of over-modulation Gain insight into audio bugs Verify adherence to technical standards Production and Marketing Avoid distorted game capture audio Reminder to sometimes mute channels in game captures (Record only sound effects in game captures and add voice and music in post)

Audio Meter Types Peak Program (PPM) Identify signal peaks Root Mean Squared (RMS) Identify average loudness Frequency Weighted Loudness (VU, CBS, ITU BS.1770) Illustrate loudness in context of hearing

Audio Meter Types Signal Phase Comparison Illustrate differences between channels Multiband Filtered Illustrate bands of frequency response Spectral Transform Illustrate signal frequency response Time graphs and statistics View level history

Game Audio Meter Calibration Calibration test tones in game Noise, Sine, Sweep, Transient Game audio channel options at full volume Or an agreed-upon calibration volume No attenuation between game output and meters Gain and stereo balance at unity

Game Audio Meter Calibration View level of test tones in meters Verify levels match reference values Adjust gain trim to compensate Offset any direct current Set meter type, scale, zero, and ballistics

Game Audio Sources Game engine or audio middleware self-metering Digital stereo and matrix surround Digital encoded surround sound Analog mono / stereo / surround Analog matrix surround sound

Audio Metering Setup Options Developers workstation sound card input Virtual audio cable Input meter routing in session of primary audio workstation Spare audio workstation Mobile recording laptop rig

Digital Audio Connections Digital Audio Optical Splitter Passive device Ground isolation

Digital Audio Connections

Digital Audio Coaxial 75 Ohm passive video splitter Digital Audio Router Handle multiple sources Mixed-type connections

Analog Audio Connections Consumer Stereo Audio Splitter RCA plugs with taps RCA Y-splitters and cables Impedance adapters Consumer Headphone Connections Stereo mini-jack splitters Inline volume trim Micro-jack adapters

Analog Audio Connections

Audio Metering Software Orban Loudness Meter

Audio Metering Software Audiofile Engineering Spectre

Audio Metering Software Programmable Analysis Software Spectrum Analyzer Pro

Audio Metering Software Pinguin Audio Meter Pro

Audio Metering Software Metric Halo SpectraFoo

Audio Metering Plug-Ins Roger Nichols Digital Inspector

Audio Metering Plug-Ins Roger Nichols Digital Inspector XL

Audio Metering Plug-Ins Flux Stereo Tool

Audio Metering Plug-Ins Digidesign Trillium Lane Labs MasterMeter

Audio Metering Plug-Ins Digidesign PhaseScope and SurroundScope

Audio Metering Plug-Ins Digidesign Dolby Surround Tools

Audio Metering Plug-Ins Neyrinck SoundCode

Audio Metering Plug-Ins Waves PAZ Analyzer

Audio Metering Plug-Ins Waves Dorrough Stereo and 360

Audio Metering Plug-Ins Nugen Audio Visualizer

Blue Cat Audio Analysis Pack Audio Metering Plug-Ins

Bias Reveal

Audio Metering Plug-Ins TC Electronic LM5 Loudness Radar

Game Audio Metering Takeaways

Use as a starting point for sound implementation volume levels

Game Audio Metering Takeaways Use as a starting point for sound implementation volume levels Coordinate work of multiple implementers

Game Audio Metering Takeaways Use as a starting point for sound implementation volume levels Coordinate work of multiple implementers Keep in view and mix as you implement

Game Audio Metering Takeaways Use as a starting point for sound implementation volume levels Coordinate work of multiple implementers Keep in view and mix as you implement Minimize mixing at the end of the project

Game Audio Metering Takeaways Use optical digital audio if possible

Game Audio Metering Takeaways Use optical digital audio if possible Use analog audio when limited by gear or situation

Game Audio Metering Takeaways Use optical digital audio if possible Use analog audio when limited by gear or situation Calibration signals in the dev game

Game Audio Metering Takeaways Use optical digital audio if possible Use analog audio when limited by gear or situation Calibration signals in the dev game Verify meters are calibrated

Game Audio Metering Takeaways Use optical digital audio if possible Use analog audio when limited by gear or situation Calibration signals in the dev game Verify meters are calibrated Instruct team how to use audio meters

Game Audio Metering Takeaways Audio meters are useful for playback system calibration but are not a substitute for it

Game Audio Metering Takeaways Audio meters are useful for playback system calibration but are not a substitute for it Audio meters are not hard and once they are set-up, you will find yourself using them more often

Game Audio Metering Takeaways Audio meters are useful for playback system calibration but are not a substitute for it Audio meters are not hard and once they are set-up, you will find yourself using them more often Familiarity with sound level properties is enhanced by regular use of audio meters