Well, actually it is the use of the Haas effect to create stereo imaging. The Haas effect actually describes under what circumstances a second identical delayed in the time domain will be interpreted as belonging to the first incident of said signal. What I meant is using this effect in a way similar to what happens in “natural” stereo: Sound coming from let’s say 45° right does not only arrive on your right ear, but on your left ear too. The difference in distance between your ears to the sound source between is let’s say 25cm. Now the sou d source is 10m away. There is not much difference in SPL between left ear and right ear, because 25cm difference is negligible at 10m distance to the source, so that can’t be how we locate sounds. There is some “shadowing” going on, because certain frequencies will be blocked by our head travelling to the left ear, that’s part of it. The other part is said 25cm difference in time the sound takes to arrive at the left ear PLUS (if present) reflections of the sound on walls, arriving much later, replacing the “shadowed” frequencies our left ear won’t get directly. Now as said, the Haas effect describes that all this summed up sound will still be recognized as ONE sound from one source.
The interesting part for us in live sound would be to use this to place a sound in the stereo image instead of using volume diffrences. The why of that is easy: Stereo is only for the people in certain positions between the mid/hi speakers. Now people standing far to the right will only hear the right speakers. If I now pan one guitar mostly to the left speakers by means of reducing the volume of it on the right speakers, people on the right side won’t hear it well. But if I use a delay to create the stereo image of the guitar coming from the left, I still get full or only slightly reduced volume on the right, so people hear both guitars everywhere AND people in the middle will still get a decent stereo feeling.
Wolfgang 5 years, 11 months ago.
