Binaural audio cues to tell the direction of the wind
E
Elise
B. Green in Discord says: "Audio cues of wind speed and direction would be very useful. The wind sound could become louder as the apparent wind speed increases. When I look directly into the apparent wind, the volume should be the same on both ears. When the apparent wind is hitting the left side of my head dead center, the noise on the right ear should be at a minimum."
Such a feature could replace explicit cues (wind arrow, red cone in compass) for advanced races.
P
Pedro
Once wind gusts are added to the simulator, these audio cues will also be useful to alert us to the presence of wind gusts.
Audio cues of water hitting the hull would also be useful to inform us when we're flying the WASZP on the foils rather than pushing through the water on with the hull.
The audio API may allow you to specify what direction the sound is coming from, but that feature may depend on what game engine is in use. Obviously the wave sound should come from the bow and maybe the stern, and the wind sounds should come from the apparent wind angle with respect to your head direction, not with respect to the boat heading.
Greg Dziemidowicz
Pedro: I've tried to do a little bit improvements to the sound of wind in the latest version. Is it any better? What area within the sound would benefit the most from the next improvement?
P
Pedro
Greg Dziemidowicz: Thanks for the improvements. I don't think I'll have time to sail this week. I'll let you know later.
Depending on which game engine you're using, you can make the sound appear to come from a certain direction. There is probably an OS call for this on the Oculus Quest. Animal perception of sound direction is not just based on loudness, it is also based on the phase difference between the two sound pressure waveforms at each ear, and some spectral (frequency response) differences. I think the OS call uses such digital signal processing effects to alter the two sound channels to provide the perception of direction.
Direction cues are strongest when they cover many frequencies. This is why the UK now uses white noise instead of a beep alert on heavy vehicles when they are moving in reverse. If you use those functions in the game engine, wind and water noises should provide strong localization cues.
Here's a list of sounds to consider:
- Wind noise coming the apparent wind direction, getting louder with at least the square of the apparent wind speed.
- Water splashing noises from the bow, proportional to square of speed through the water.
- Wooshing sound coming from the stern when water speed is high.
When close hauled, the wind sounds should be loudest, and the bow spray and wave crashing noises also, since the boat is going into steeper shorter apparent wavelength waves. Downwind you may hear mainly a trickling sound from the wake near the transom. Noise from the bow will be less because the apparent waves aren't as steep, and there will be less splashing, if any.
You could put a call out for sailors to donate some sound clips from the bow, stern, and helm station, both upwind and downwind. Ask over in reddit.com/r/sailing. I suggest the microphone be placed near the source of the sound. Asking for sound clips can simultaneously count as marketing and development, so it will be like cloning yourself. Even if you don't receive clips, you'll still benefit.
Water sounds must be tied to water speed and apparent wind speed, not speed over ground. Otherwise, when you add current, you may have to rewrite the water calculations.
A note on proportionality: if the sound level control is linear (e.g. amplitude or percent), then use an exponent of the speed to control sound level; maybe 2.0 to start. If the volume control is in decibels, then perhaps you can use a linear factor (exponent of 1) because decibels are logarithmic, so they'll have an exponential effect on amplitude. In that case, adjusting the volume would be with a multiplier, not an exponent.
While you're tweaking the sound coefficients you may find it convenient to make a volume slider for your own use. If you make those sliders available to end users, you'll have added a user customization. Pie in the sky: you could mine the user settings to crowd source your default sound tweak values, but I'd not count users who never adjusted the sound sliders.
P
Pedro
Greg Dziemidowicz: I just sailed the WASZP, dinghy, and the monohull. Between my currently very limited guardian space and my mucking about experimenting, I did not finish well. Regarding the sound, all I heard was the voice of god telling me about the race course, and the buoy bells. I did not hear any sounds of wind, or waves hitting the hull, or wake. I heard no wind at all.
Greg Dziemidowicz
Pedro: Lack of sound... sounds like a bug. You could try reinstalling the game to see if it helps. I will also look on my end