How many dimensions do we hear in


Do we hear in one , two or three demensions with our hearing. ? With ear buds verses headphones a speakers. I am thinking only 2 with iem,s and three with headphones or speakers .help please



Four. Time is perhaps the most important dimension in the listening experience. If you do not count time, but only our three perceived physical dimensions then it does depend on whether we are listening to speakers or headphones. It might be argued that even when listening to speakers three dimensions is still only an illusion. This more true when we experience three dimensions when listening to headphones (cans, iems or whatever).

Interesting discussion topic, I hope that we get more than just my little comment.



Me too. I did not think of 4. Good point though , But is a delay a dimension ? So what you are saying up down left right and front to back that is three. Now with iems, is there really a sound stage . I never hear much more like placement of instruments and louder or lower to give you close or far. This should be a Paul post . Lol. Did you read today’s.?



In the real world, we spatially hear in three dimensions.

During playback, we hear in one dimension (left and right) but our brains happily fill in depth through positional cues (less high frequency and more room sound moves instruments back in the soundstage). Thus, we hear in two dimensions, given a good stereo recording.

Sometimes we hear a third dimension (height). I have yet to learn of an explanation of how we can possibly get height cues out of stereo playback of a microphone pair.

(We also hear the room, for good and bad. This sound is three dimensional.)

In the real world, we get height cues through the differences in frequency and timing response created by the shape and size of our ears, as well as the amount of time it takes sound to travel around our heads. This is also how we locate a sound behind us. Each of us learns the sound of our ears with time and experience. If an outer ear is damaged, we need to learn all over again.

Headphones are inherently different from speakers as the right ear does not hear the left transducer and vice versa. Some amps have crossfeed which helps, but is not the same sound as speakers.

Headphones emphasize room sound, reverb, ambiance, transient attacks, intakes of breath, instrument noises (such as pad sounds of an oboe) and other subtle sounds. This characteristic additionally makes headphone listening fundamentally different from listening to speakers.


Great explanation and thanks. What about IEM,S. As there is no ear interaction ?



IEMs are just like headphones, but there is less frequency variation as our ear canals are more similar to one another than our pinnae.


We only use 2 dimensions to hear - time and air pressure level. All other elements (depth, height, width) are processed by our ears/brain from the 2 elements. Subtle timing delays from 1ear to the other allow our brains to reconstruct a convincing 3 dimensional soundscape from just 2 dimensional information. Our ears are like 2 independent Fast Fourier Analysers, acting as at least 3rd order comparators. This is even before our memory overlays “expectation corrections”.


There is an incredible amount of processing that goes on in that lump of wetware between our ears. I find it amazing that we can sense depth and height with just two sensors. As much and as little as medical science understands our bodies the brain may be the least understood organ. One factor I find interesting is that our sensory abilities seem to have little if any association with intelligence.



Like any any other sense organ, our ears can be trained, and indeed become more sensitive the more we use them for discriminating minute details and tonal changes. This is why non audiophiles often scoff at our expensive habit. Intelligence, as you say, has nothing to do with it. It just requires a commitment to train.

Our sense of smell can be similarly trained. At the elite level, a highly trained nose is worth a six figure salary in France at one of the perfumeries. Unfortunately they are required to live a life of abstinence (eg from alcohol).


Great reading. So some say 2 and some 3. I tend to go with the two concept in that time and pressure or loudness is really all there is , as we make up the rest . I read some where of a test having someone stand in front you a about 10 feet away and having them move over slightly after each anoucement . And how we can tell they have moved over. Very interesting stuff. I have had countless arguments with people claiming to hear this vast sound stage with Iem,s in there ears. Where I hear a stage but nothing to the proportions some people claim to hear. I also have a phonitor headphone amp. It has some really nice features allowing you to move the sounds around a bit in you head with headphones. Thanks people for the ongoing knowledge .


stereophilus said: Our ears are like 2 independent Fast Fourier Analysers, acting as at least 3rd order comparators. This is even before our memory overlays "expectation corrections".

A delicious, excellent summary.

alrainbow said: So some say 2 and some 3.

Two is more correct, and one may be the most precise. We have only two ears. The information we receive is only from left to right - a straight, one dimensional line.

Depth, height, front, back, movement, etc. are all constructed by our internal warmware from the information our ears present to the brain.

Fascinatingly, those with hearing in only one ear, or a single eye, can process depth perception as the brain kicks in and makes determinations. Close one eye and you can still process what object is in front of another. It is especially easy if one of the objects move or you yourself are moving.

alrainbow said: I have had countless arguments with people claiming to hear this vast sound stage with Iem,s in there ears. Where I hear a stage but nothing to the proportions some people claim to hear.

While we cannot know what another hears, I think they are correct.

The first time one listens to headphones the sound stage is oddly compressed with the instruments strung out along a clothesline anchored between your ears. There is no depth and no sound beyond your ears.

With experience, one's brain learns to interpret this information as a satisfying listening experience. Your brain creates soundstage, depth, etc. You also learn to appreciate those things headphones/IEMs are really good at, such as resolving detail. Headphones never sound like speakers, but they can be just as satisfying in a different wway.

Headphones/speakers/live music - all very enjoyable, each unique.