a proper 2 channel system, setup well, can literally take breath away and extract tears right from the eyes. Even most people with high end audio kit dont actually know what their stuff is capable of because they've never actually heard it setup properly.
A good 2 channel can make sounds come from right behind your head, and when you turn to look, theyre still there.
its the closest thing to magic ive ever experienced outside mushrooms lmao. And you dont have to play with sliders if whoever mixed the music was really good at their job either lol.
Replying to myself, because i feel like rambling and sound is a deep deep passion of mine.
youre brain is incredibly sensitive to time domain information in sound. Its how we tell what direction a sound comes from. your brain can discern fractions of a millisecond in the time domain and how sounds from different angles hit each ear drum at a different time, allowing the inference of locality of the sound.. If a speaker system is capable of timing the phase of the sine waves being produced properly, they can play the same interval between sinewaves that your ears process when a sound is directly behind your head. If you turn your head to listen to something that was behind you, you now hear it coming from in front of your head. Obviously. The same is true with a set of properly setup stereo speakers. Because the brain cant tell that theres nothing there making a sound, because the time domain information being processed by the brain tells it that there is, in fact, something there making a sound.
Its a wild experience. very psychedelic to turn your back to a set of 2 speakers after hearing them play a sound behind you, only to find that the sound is now coming from in front of you as if there was actually something there making the sound. The result of this, when its setup properly, is literal* holographic imagery. Your brain implies the presence of something there, simply because thats where a sound is coming from, and the sound is so perfectly reproduced its indistinguishable from the real thing. The better the phase accuracy and the more accurate the frequency response of a speaker is, the harder it becomes for the brain to tell the soundstage apart from reality. Something thats physically there.
And speakers do, in fact, get sooooooo good, that the brain cannot distinguish the sounds from something thats physically there. Standing in space and moving around, as real as anything else in the room.
And btw, humans have WAY better ears then dogs. There is a huge misunderstanding there. Dogs can hear a wider range with more decibel sensitivity. Thats it. This does not make good hearing. Humans have the ability to distinguish detail, and differences in sound, and directionality so well, we evolved out of our ability to be able to move our ears a long time ago. Most apes did. You dont need to hear under 20hz and over 20k. Theres no useful information in the audio band at those frequencies anyway. All being able to hear those frequencies does, is make it harder to tell what direction sounds are coming from, and harder to distinguish where one sound stops and another starts.
Most animals struggle to tell what direction a sound is coming from, or what it even is, while literally starring right at it, with cup shaped ears pointing right at it lol. Much like with eyes and vision, birds of prey are the only thing that have us trumped on hearing fidelity and detail/direction discernment.
Range does not make good hearing, detail and direction discernment makes good hearing. And to be able to discern detail and directionality in sound, you have to remove the useless information from it first so that your brain can be sensitive to such miniscule time domain information. And thats way more likely to save your ass in the wild too, then simple range and sensitivity.
Theres a reason rooted in physics for this too, and it has to do with the speed of sound within our atmosphere. Sound moves at about 988 feet per second. About 1 foot per milisecond. A frequency above 20,000hz has a peak to peak wavelength of about 20 milimeters.
Get below 40hz or so, and the wavelength measurement is like 20 feet. Its not physically possible to tell the direction of sounds with waves that big or small. At the low end the measurement gets bigger then your entire body, beyond that information isnt retrievable anyway becuse your skin cant even tell it apart from a breeze, and above 20khz, the wavelength is around the size of an average ear drum, rendering information retrieval totally useless anyway because even if you could retrieve the information, it cant possibly be accurate. It would break the laws of physics to make it happen. Its just junk information that means nothing to anything made out of meat.
In water this works differently, because the speed of sound is different. Proposes dont count here lol. Under water, the range that can contain usable information in the time domain extends exponentially because the speed of sound goes way up, but so does amplitude of a sinewave (distance from sine peaks to neutral with a given amount of energy at a particular frequency) You've prob stuck your head under water at a lake, and clearly heard a boat motor or several, only to pop up, and notice there isnt a single running boat in sight and you def cant hear one.