me personally I think that this would be great on here! having sounds have there little space all around you with the 3d sound effect would be pretty nice.
me personally I think that this would be great on here! having sounds have there little space all around you with the 3d sound effect would be pretty nice.
Comments (5)
Stereo works by utilizing two channels: right and left. You can get a 3D effect by involving a little bit of trigonometry and such to decide the amplitudes of sounds coming through either channel. Audiotool doesn't have any math stuff for timeline automation nor does it have 3D stereo devices, but it does have stereo control devices and you can always manually plot trigonometric graphs in automation strips in the timeline. Gets easy to do once you figure out what you're doing.
but even still i think they should add it
Uh, not quite.
Amplitude is only one factor when determining the location of a sound source. Frequency content is highly important, as is phase correlation.
I don't think getting into the details of all of the psychoacoustics involved is really necessary here, but in essence:
For determining height; resonance at about 8kHz is key - a dip is observed in this frequency with a fairly narrow Q factor when a sound is below, and even inline, with the listener. A boost starts to occur when the source is above the listener.
Similarly a resonance, this time with a wider Q factor, is observed when determining position in front or behind the listener with a slight boost for sounds in front, but an increasing dip as sounds travel to the rear of the listener in relation to the left-right axis (the more directly behind, the larger the dip).
The further sounds are from the listener, the fewer high frequencies are heard - this is due to those frequencies losing energy over time, as well as to do with refraction and reflection.
Sounds on one side will be heard in both ears, however the far ear will recieve these sounds with a delay of up to 7ms depending on the angle of the source in relation to the listener. Not only will they be delayed, but they will also be "shadowed" with a shelf filter type effect applied at roughly 3kHz dampening the higher frequencies to account for the size/density of the head, and the refraction/reflection process involved for the sound to reach the far ear.
There are other factors, but these are the easier ones to replicate.
-This is part of the research involved in my masters project; I can cite all of the sources if you like.
Hope this helps!
Yeesh, that's a lot of stuff to determine position of stuff. Are there any equations that can be used? Like, suppose I try to use Audionodes.com or I try to use
AudioContext()stuff in JavaScript, what equations can be used to automate all the frequencies and biquad filter stuff based on the XYZ values of a 3D point?Well, you basically have to correlate the x y z values with how much filtration or delay is being applied to the signal.
Yes, there are equations for sure, but different papers will provide different ones for a variety of reasons.
The way I did it in the plugin I built was far more linear than it would ideally be, and the scaling was based on trial and error.
As for biquad inputs; you're typically only adjusting the gain of a filter, so as long as you have a way to adjust the gain rather than provide a fixed value to the filter coefficient calculator, you don't need to mess with the actual filter or it's calculations.
I built my own biquads for my purpose, so that was particularly easy to adjust.
Unfortunately biquads are rather unstable and bring their own characteristic phase issues with them which caused me a few problems.