Many years ago(at least a decade), I had heard a speaker setup that struck me due to its stereo separation. I can't remember any specifics about it, but sure it was something to do with psychoacoustics. The best way I can describe it is that I was able perceive stereo audio where the source was physically in excess of the speaker location itself, where the sound is about 1 foot in extension of where the speakers actually are.
In a normal setup, the most "left" or "right" I could hear a sound is directly where the left or right speaker is. Let's just talk "left" for example. My initial assumption is that I perceive the left's speaker's position as a function of how much sound also bleeds into my right ear, either directly(well, around corners, although stifled) or indirect reflections. It was in an open area so I doubt very much reflections came back. I was standing only 3-5 feet from the speakers themselves.
From there, I assumed that if I just simply inverted the phase of that signal, attenuated it, and broadcast that through the right speaker, maybe that would cancel out how much reaches my right ear and trick me into thinking it's more left. That didn't work for maybe obvious reasons to some. I looked into phase, delay. Perhaps it is the Haas effect, but I couldn't replicate it(seems that was more about trying to make a mono signal stereo-ish, no so much "enhancing" stereo).
I'm wondering if anyone knows what I'm talking about, and could point me in the right direction to learn more about whatever signal processing was involved here.
In a normal setup, the most "left" or "right" I could hear a sound is directly where the left or right speaker is. Let's just talk "left" for example. My initial assumption is that I perceive the left's speaker's position as a function of how much sound also bleeds into my right ear, either directly(well, around corners, although stifled) or indirect reflections. It was in an open area so I doubt very much reflections came back. I was standing only 3-5 feet from the speakers themselves.
From there, I assumed that if I just simply inverted the phase of that signal, attenuated it, and broadcast that through the right speaker, maybe that would cancel out how much reaches my right ear and trick me into thinking it's more left. That didn't work for maybe obvious reasons to some. I looked into phase, delay. Perhaps it is the Haas effect, but I couldn't replicate it(seems that was more about trying to make a mono signal stereo-ish, no so much "enhancing" stereo).
I'm wondering if anyone knows what I'm talking about, and could point me in the right direction to learn more about whatever signal processing was involved here.
There are SOOO many tricks to the recording art. One example, pan your dry signal over to one side, and play the same signal through the right, but the right is delayed a small amount. It fools your ears.
That's precisely what the Haas effect is, from my understanding, and I get that effect(sounds sterio-ish when in fact its a mono recorded signal), but that is not what I experienced. I do all sorts of these tricks while recording, but this is one I have never been able to figure out. This was an existing, normal stereo recording, that sounded more "spread out" from what the physical speaker placement should have allowed. It's very hard to describe.
Not only can the virtual sound source appear more to the left or right of the actual loudspeakers. The virtual sound source can appear beyond the loudspeakers, or even behind you! A good example is Pink Floyd's classic Animals (I can't remember which track, but psychoacoustic illusions were extensively used on the whole record, like a dog barking behind you, etc.).
This kind of thing was popular in the 1980s. At the playback end of it was Carver's C9 Sonic Holography, Polk made a line of speakers that employed inter-aural cancellation, there was some box called the "Omnisonic Imager". The modern derivation of this stuff is referred to as Ambiophonics.
Maybe but what I wrote about was done at the recording studio. I don't know how. It works with all plain stereo playback system.
Lots of things that can be done, including feeding a small amount of reversed-polarity signal to the opposite speaker.
Some analysis of a HRTF could yield interesting theoretical results which could be fun to put into practice.
Chris
Some analysis of a HRTF could yield interesting theoretical results which could be fun to put into practice.
Chris
Dogs, Pigs and Sheep. I was not aware of this affect, but the distant sheep are funny.
With electrostatic loudspeakers, that is with a flat phase curve over a broad audio range (250 - 20k min) - so not crossover filtering as in magnet-driven units (amplitude near flat, but all phase rotators), I'm always amazed to realise that I have a grand piano in my small living room. It's rolled to the spot just where the dinner table happens to be. I's front wheel is so close I keep my legs folded.