Reference Mix for Game Audio

This is something that I have been thinking about a lot lately and have been trying to do with my current project. Create a reference mix to be used through the production cycle on a video game.

Shaun Farley wrote a fantastic post on Dynamic Interference about Ideas for the Use of Loudness Metering in Game Audio that triggered this post. I highly recommend reading that article and his other recent post on loudness metering

I talked about calibrating monitors and a few general mixing ideas in my last two posts here and here. Go read those for a general understanding of level standards if you are new to all this.

So the idea I'm discussing here is creating a reference mix. This is something that I feel would cut down on extreme crunch time at the end of the production cycle, which seems to be inevitable for the audio team. The reference mix doesn't have to be anything crazy. During preproduction (if you get that luxury) create a few simple assets and mix them to the standard level you want to set through out the game. These assets could just be an ambience bed, simple dialogue (enough to get the feel of the mix across), mocked up weapon sounds (if you have weapons), simple UI sounds, and possibly some other common sounds (footsteps and other foley, collisions, explosions, etc.) Once all these assets are gathered do a simple implementation and create a scene. Then mix.

Once you have this mix set you'll have a nice template premix to base everything else off of. As you create real game assets you can level them to the premix. Then during post production it only takes a few quick passes to get the whole thing mixed correctly because you took the time to premix.

There are still, of course, a few issues that come into play here. One is not having the time to do this preproduction step. It's not uncommon for audio people to be brought on at the very end of the project. The other is when your higher ups come back to you at the end and say "turn up the volume." Which is another not-so-uncommon issue within the game audio world since we do not have any officially set standards. These are issues that have to be solved by us audio people getting the point across that audio is important to the project, and so is dynamic range.

I would love to hear what other ideas and comments people have on using a reference mix for game audio.

Mixing in a Small Room

A few days ago I wrote a post about mixing levels and game audio mixing. This post will be an addendum to that one.

In that post I suggested using a 79dB at -20dBfs pink noise calibration level. This is a good level if you are mixing in a large room and are seated a decent distance from your speakers. If you, like many people in the game audio industry, are sitting only a couple of feet from your speakers in a small room then this level is going to seem way too loud when referencing other material and therefore make your mix too quiet. A more practical level to set would be 73dB or lower for this environment.

For extended reading on this topic there is a great gearslutz post in it: Mixing levels and dynamics: Hand me the tylenol.

Also, here are the Dolby Facility Requirements that state that the theatrical mixing level of 85dB should be from a listening position of at least 13 feet and 4 inches from the screen.

Mixing Levels and Game Audio Mixing

Standard mixing levels and monitor calibration are two things that everyone working with sound should understand. Most people starting out in sound don't even realize that they should be calibrating their monitors for a specific level standard.

As far as game audio goes, there is no existence of a standard mixing level. It's understandable why it would be difficult to create a mix standard for games though. In a completely interactive medium, you never know how or in what order the sounds are going to play. This unpredictability makes mixing even more important in game audio.

Mixing for games should start before the audio assets are even thought about. A mixing level should be selected and monitors calibrated before the sounds are created and implemented. I would suggest 79dB at -20 dBfs full pink noise, but it's up to you and your studio to set the level. Next, a focal point should be determined to mix around. For most large scale games that would be dialog, but for some games it may be another important sound. Once production of the sounds begins everything should be "premixed" as it is created and implemented. Time should be set aside for just mixing at the end, but if for some reason you get pushed right up against the deadline (not so uncommon) your overall sound will already be somewhat close to being leveled correctly.

I understand that trying to adhere to mixing standards isn't always easy. Especially if you work at a studio that keeps telling you to turn the volume up. It is our duty as sound designers and implementers to deliver the best sounds possible with the best mix possible though.

Here are a few links that go into mixing for games more in depth:
GameAudioMix: Top 11 Video Game Mixing Tips
Game Audio Podcast: Episode #10 Reference & Mix Level Standards
Gamasutra: The Game Audio Mixing Revolution

This is a great gearslutz post on standard mixing levels for several different mediums.

And here are some great references on monitor calibration and standard mix levels:
Blue Sky Calibration Instructions and Files
Dynamic Interference: Quick and Dirty Monitor Calibration
Avid Audio Forums: Room Calibration for Film and TV Post
Calibrating The 5.1 System by Bobby Owinski
Gearslutz: Dolby Facility Approval Requirements
Dolby 5.1-Channel Production Guidelines

I don't claim to know everything about mixing standards and calibration, but this should be a good starting point for anyone interested in these topics. If you have any insight, comments, or questions feel free to comment or shoot me an email.

Addendum: Mxing in a Small Room