here's one:

http://www.vescofx.com/vfxFreeHaas

That one doesn't go low enough. Look at this video, the Haas effect starts at 0.1ms basically: https://www.youtube.com/watch?v=RP5kg3uNekg

velocity = the speed of something in a given direction. a satellite in space is moving extremely fast (17,000+ miles per hour), but you perceive it as moving only a few inches per second. objects that are closer appear to be faster, objects further away appear to be slower. incorporating this phenomenon into your mixes can help achieve a sense of depth (ie. don't quickly pan sounds that you want to appear more distant, pan them slowly, as you would observe that satellite in the night sky slowly orbiting @ 17,000+ miles per hour)

do we have to account for the effects of relativity in our mixes?

I like to use very small rooms with zero pre-delay just to color a sound
sometimes.
This can work very well when you just want to create a little space to
make the track sound unique from the other tracks.

Over-all it can help parts stand out better.

Is this specifically for orchestral music? I am looking for something to position voices and natural noises in a 3D panorama (radioplay type of scenario).

delay and reverb?? and recording things that have depth to begin with

you don't even need to use plugins for delays, just copy a bit of audio and change the volume or processing a little bit if you want a subtle effect