Audio Metering for Game Developers

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Audio Metering for Game Developers
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Audio Metering for Game Developers

• Jason Cobb
• Game Audio Design
• GL33k
• The Sound Department Austin

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Game Audio Metering Room Survey
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Game Audio Metering Room Survey

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

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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?

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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?

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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

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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

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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

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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

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Game Audio Metering Potential Users

• Quality Assurance
• Identify cases of over-modulation
• Gain insight into audio bugs
• Verify adherence to technical standards

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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)

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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

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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

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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

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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

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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

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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

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Digital Audio Connections

• Digital Audio Optical Splitter
• Passive device
• Ground isolation

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Digital Audio Connections
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Digital Audio Connections
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Digital Audio Connections

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

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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

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Analog Audio Connections
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Analog Audio Connections
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Audio Metering Software

• Orban
• Loudness Meter

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Audio Metering Software

• Audiofile Engineering
• Spectre

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Audio Metering Software

• Programmable Analysis Software
• Spectrum Analyzer Pro

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Audio Metering Software

• Pinguin
• Audio Meter Pro

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Audio Metering Software

• Metric Halo
• SpectraFoo

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Audio Metering Plug-Ins

• Roger Nichols Digital
• Inspector

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Audio Metering Plug-Ins

• Roger Nichols Digital
• Inspector XL

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Audio Metering Plug-Ins

• Flux
• Stereo Tool

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Audio Metering Plug-Ins

• Digidesign
• Trillium Lane Labs MasterMeter

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Audio Metering Plug-Ins

• Digidesign
• PhaseScope and SurroundScope

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Audio Metering Plug-Ins

• Digidesign
• Dolby Surround Tools

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Audio Metering Plug-Ins

• Neyrinck
• SoundCode

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Audio Metering Plug-Ins

• Waves
• PAZ Analyzer

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Audio Metering Plug-Ins

• Waves
• Dorrough Stereo and 360

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Audio Metering Plug-Ins

• Nugen Audio
• Visualizer

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Audio Metering Plug-Ins

• Blue Cat Audio
• Analysis Pack

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Audio Metering Plug-Ins

• Bias
• Reveal

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Audio Metering Plug-Ins

• TC Electronic
• LM5 Loudness Radar

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Game Audio Metering Takeaways
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Game Audio Metering Takeaways

• Use as a starting point for sound implementation
  volume levels

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Game Audio Metering Takeaways

• Use as a starting point for sound implementation
  volume levels
• Coordinate work of multiple implementers

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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

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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

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Game Audio Metering Takeaways

• Use optical digital audio if possible

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Game Audio Metering Takeaways

• Use optical digital audio if possible
• Use analog audio when limited by gear or
  situation

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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

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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

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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

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Game Audio Metering Takeaways

• Audio meters are useful for playback system
  calibration but are not a substitute for it

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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

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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

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