Common Questions about HDR

We recently had a great call with one of our HDR users that turned into an in-depth discussion about implementation approaches and creative uses. The conversation helped us expand our FAQ documentation, making it clearer for everyone using the system.

If you haven’t seen it already, a feature set overview video for SweejTech HDR can be found here

Basic Concepts

What is the resting level in HDR and why is it set to 80?

The resting level of 80 isn't arbitrary - it corresponds to where the stapedius reflex naturally occurs in human hearing (around 80 dB SPL at 1 meter). When sounds are at this level, the HDR system will not have any effect on your mix, making it an ideal baseline. Think of it as your natural "home base" for sound levels.

What kind of loudness ranges should I work with?

For most sounds, working within a range of 80-100 is very reasonable. While the system can handle values up to 150, these extreme levels are best reserved for special dramatic effects. What's interesting is that even small changes can be very effective - just 6dB of headroom above resting can create impactful ducking behavior.

Implementation

How should I approach HDR implementation?

Start with all sounds in HDR at resting level (default 80) and consistent reference monitoring levels. Establish your ambient sound design as a foundation, then adjust loudness values upward for sounds that need to create space in the mix.

While music and dialogue often need special consideration, it's better to start with everything in the system and switch HDR modes or bypass HDR only if they specifically don't work well. Document your loudness ranges and reasoning - this becomes crucial as your project grows.

How should I handle sustained or looping sounds?

Sustained sounds need careful attention. They should generally stay near or below resting level to avoid constant mix movement. Consider using different loudness levels for different states of the same sound, e.g. first person vs third person perspectives.

What release speed should I use?

Release speed typically works well between 20-60 dB/second. Think of it as a balance: faster release creates snappier response but risks more pumping, while slower release sounds smoother but can hold the mix down longer. The key is matching your sound tail lengths to your release speed for natural results.

Technical Considerations

How do attenuation and HDR work together?

HDR calculations happen after attenuation, which creates some interesting behaviors. Very loud sounds can override normal attenuation behavior - when a sound's loudness exceeds resting level, it won't attenuate normally until it falls below resting. Using steeper attenuation curves for loud sounds helps maintain control over this interaction.

What performance benefits does HDR offer?

HDR isn't just about mixing - it also offers valuable optimization opportunities. The system can automatically stop distant quiet sounds from playing and cull low-loudness ambient sounds when appropriate. It helps manage voice counts and can be particularly efficient when working with reverb and complex spaces. Think of it as getting mixing and optimization benefits in one package.

Creative Uses and Philosophy

Is HDR only for dramatic moments?

While HDR is excellent for managing peak moments, it's equally valuable for subtle mix movements. Using gentle 6dB changes with slower release speeds can create beautiful, nuanced transitions. The system is incredibly versatile - it's as much about delicate mixing as it is about managing dramatic moments.

One powerful creative use example is a low health state. You can use high loudness values, 50+ dB above resting level, to create a suppressed feeling - imagine playing a loud muffled sound that pushes other sounds away. By carefully shaping the release curve, you can control how sounds return to normal. This creates sophisticated state changes without relying on traditional filtering techniques.

Best Practices

What are common pitfalls to avoid?

The biggest pitfall is over-complication. Avoid combining too many mixing systems or adding excessive modulation on top of HDR, as this can make it impossible to predict final volume levels. Keep your approach consistent and maintainable. Always test with real gameplay scenarios - behavior can change significantly in full gameplay conditions, where many sounds can compete for space in ways that are difficult to test in isolation.

How should I approach testing?

What works in small tests might behave very differently at scale with many sound sources. Mix throughout development rather than treating it as a final phase. Start early to understand the tools and workflow, and regularly test with multiple sound sources in real gameplay conditions.

How should I approach sound design for HDR?

Design your sounds with HDR in mind from the start. Consider how amplitude variations within a sound will interact with the system, and how different sounds will layer in dense scenarios. Pay particular attention to sustained sounds and how their timing relates to your HDR release speeds. The goal is to work with the system rather than trying to force it to behave differently.

Conclusion

Whether you're creating subtle transitions or dramatic gameplay moments, understanding how to work with SweejTech HDR will help you achieve more sophisticated and maintainable mixes.

Want to give it a test? Contact us at hello@sweej.tech to arrange your free trial license! 

Got questions about HDR, SweejTech, or anything game audio? Join our Discord for in-depth technical discussions together with other developers!