# Wavelengths and Hearing

#### The Introvert

##### Goose! (Duck, Duck)
Maybe this is completely wacky, but does the wave physically interact with the air column it produces? Is the number of columns produced per second (and thus the tone) simply the number of times the wave cuts into the column of air as it passes through from either side?

Every time it passes through, it would create a short blast of air of given length (in the case of the graph, 1 pi). The number of these short blasts would be predicated on the frequency of the wave, which would give you the number of blasts per second.

#### Duxwing

##### I've Overcome Existential Despair
I was just trying to explain how interpreting a tone as an average of the wave is misleading. This isn't how sound works.
A pure tone is the average of the wave, and that's what I wanted to prove. A more complicated tone is... more complicated.

It would be more accurate to say that the tone perceived is a complete cycle of peak and trough.
@The Introvert ^^This is what you're looking for.

-Duxwing

#### The Introvert

##### Goose! (Duck, Duck)
This is what you're looking for.
I've gotten so many answers here I don't know what to do...

It's gone from being the peak of the wave to the whole wave to the mid-line of the wave to the wave not even being a sound and back again.

Is this at least close?
Maybe this is completely wacky, but does the wave physically interact with the air column it produces? Is the number of columns produced per second (and thus the tone) simply the number of times the wave cuts into the column of air as it passes through from either side?

Every time it passes through, it would create a short blast of air of given length (in the case of the graph, 1 pi). The number of these short blasts would be predicated on the frequency of the wave, which would give you the number of blasts per second.
In this scenario, you are perceiving the entire wave, but the tone (sound) is the mid-line. I don't know if I am correct or not about the physical encounters (if any) between wave and air tunnel (or even if there is a tunnel) or what. I haven't looked at the video yet. This question has proved to be far more exhausting than I first imagined, which is kind of awesome.

Edit: watched the video and it was helpful. So the wavelength is a representation of the differences in the pressure of air caused by the thing that caused the sound, if I understand correctly.

The actual sound heard, then, is the differences in air pressure hitting your ear per second?

#### walfin

##### Democrazy
So then, in theory, the sound we hear (read: perceive) is running along the x-axis with slope 0?

Just double checking.

Perhaps my thought process is correct then...

So, to reiterate again: The pressure oscillation (sine wave) produces a sound (straight line) that splits the sine wave down the x axis with a slope of 0. Yeah, that's definitely what I'm thinking.

So how does that work then? The pressure from the peaks and troughs of the oscillation produces a stream of sound (air columns?) that beat at a certain frequency, giving pitch (for instance, 440 air columns produced a second would make the sound A)?
This is perhaps a bit out of point, but the violin etc waves aren't just a pure 440 Hz wave, they can be broken down with Fourier transform into multiple sine waves of different frequencies.

The "air columns" (or water columns or whatever) are themselves the oscillation. The graph is simply a reflection of how far each "air column" is displaced from its equilibrium position (e.g. to the right/left) (if it's an amplitude/displacement graph) or how one particular air column moves with time (amplitude/time). Yes, 440 air columns would produce the A (if they are equally spaced).

#### Montresor

##### Banned
I was trying to back off this thread but I can see you still are getting nowhere.

The tone does not exist in nature. The nature of sound is that it must be perceived to exist as sound.

The sine wave (being two dimensional) does not exist in nature (at least not the way you seem to want it to). You can't characterize a sound wave as a sine wave in the physical world. The "x-axis" you keep describing is quite difficult to conceptualize if you take a step back; it's not really even there.

Sound waves are a 3-dimensional concept. As a lump of matter vibrates, it causes disturbances in the air around it. These disturbances oscillate outwards in all directions, like a sphere or a globe, that inflates over time.

The pressure gradients we're referring to are also a very abstract idea. To be understood, you need to look at a moment in time. There really is no "wave" in the sense that you understand waves.

If you could freeze time you would see a number of spheres emanating from the vibrating piece of matter. Like a jawbreaker candy, yes, a jawbreaker. where the sweet sweet center is whatever piece of matter is vibrating. Some layers would have low pressure (troughs), and some layers would have higher pressure (peaks). The amplitude of the wave decreases with distance from the source.

It's the high pressure peaks that cause stimulation in the eardrum, thus commencing the process of perception, which we are absolutely not going to talk about in this post.

You can't characterize the tone as a straight line, no matter how much you want to. Even pure tones are subject to Fourier analysis as Walfin said.

If you continue trying to break the concept down into its constituent parts you're going to continue to miss the mark. You cannot force your idea to be right.

I totally understand the desire to comprehend, plus the mental exercises of abstraction and conceptualization. Your preliminary assumptions are flawed thus this whole thread is continually getting nowhere.

#### The Introvert

##### Goose! (Duck, Duck)
I was trying to back off this thread but I can see you still are getting nowhere.

The tone does not exist in nature. The nature of sound is that it must be perceived to exist as sound.

The sine wave (being two dimensional) does not exist in nature (at least not the way you seem to want it to). You can't characterize a sound wave as a sine wave in the physical world. The "x-axis" you keep describing is quite difficult to conceptualize if you take a step back; it's not really even there.
I understand this.

But as Dux said, to fully understand something, you must break it down to the least complex and most basic properties. Even if that involves using something that does not actually exist.
Sound waves are a 3-dimensional concept. As a lump of matter vibrates, it causes disturbances in the air around it. These disturbances oscillate outwards in all directions, like a sphere or a globe, that inflates over time.

The pressure gradients we're referring to are also a very abstract idea. To be understood, you need to look at a moment in time. There really is no "wave" in the sense that you understand waves.
I'm using the terminology, again, simply because it's easier to talk about. 3-dimensions are obviously much more complex, and thus not as easy to fully understand. I know that the discussion is effectively meaningless, as the topic we are talking about is meaningless.

I've noted multiple times in this thread that there is an underlying question (that I still have yet to unveil). The root of the discussion is centered around this question for me; this is why I am so insistent of completely analyzing something that seems to be irrelevant.
If you could freeze time you would see a number of spheres emanating from the vibrating piece of matter. Like a jawbreaker candy, yes, a jawbreaker. where the sweet sweet center is whatever piece of matter is vibrating. Some layers would have low pressure (troughs), and some layers would have higher pressure (peaks). The amplitude of the wave decreases with distance from the source.

It's the high pressure peaks that cause stimulation in the eardrum, thus commencing the process of perception, which we are absolutely not going to talk about in this post.
Very nice analogy here.

As a side note, I would love to discuss the intricacies of perception at some point with you, because you're very technical/analytical about the matter.

If you continue trying to break the concept down into its constituent parts you're going to continue to miss the mark. You cannot force your idea to be right.
Au contraire, mon ami(e)!
I totally understand the desire to comprehend, plus the mental exercises of abstraction and conceptualization. Your preliminary assumptions are flawed thus this whole thread is continually getting nowhere.
Yes, my preliminary assumptions are indeed flawed. I don't think the thread is going nowhere though; look how much pertinent and valuable information has been discussed!

#### Hawkeye

##### Banned
I'm waiting for the underlying question.

#### Minimalist

##### "The wise man knows that he knows nothing" or some
A particle is consciousness' reduction of infinite to the finite nature, which thereby forms reality. Consciousness is the filter, the limiting factor, the constructor of actuality from possibility. The sound we observe has only one interpretation solely because it is being observed by an observer with limited perception. I present these ideas because I have been exposed to them before and am currently reprocessing them. The universe, if infinite, cannot be perceived by the finite. The finite, consciousness, must therefore reduce infinite to the finite, a wave to a particle. The whole must be reduced to the average in order to be perceived. Relativity depends upon finite observers, if reality is infinite, then these finite observers must be a result of limited perception. If everything were one, then it could not be observed. Consciousness, therefore, is the restriction of all possibility to one. That's not to say that all possibility is not occurring simultaneously, merely that my and your perspectives are one of infinite perspectives which make up a much larger infinite.

#### SpaceYeti

##### Prolific Member
^ So, what, you're practicing your nonsense?

#### TimeAsylums

##### Prolific Member
I was trying to back off this thread but I can see you still are getting nowhere.

The tone does not exist in nature. The nature of sound is that it must be perceived to exist as sound.

The sine wave (being two dimensional) does not exist in nature (at least not the way you seem to want it to). You can't characterize a sound wave as a sine wave in the physical world. The "x-axis" you keep describing is quite difficult to conceptualize if you take a step back; it's not really even there.

Sound waves are a 3-dimensional concept. As a lump of matter vibrates, it causes disturbances in the air around it. These disturbances oscillate outwards in all directions, like a sphere or a globe, that inflates over time.

The pressure gradients we're referring to are also a very abstract idea. To be understood, you need to look at a moment in time. There really is no "wave" in the sense that you understand waves.

If you could freeze time you would see a number of spheres emanating from the vibrating piece of matter. Like a jawbreaker candy, yes, a jawbreaker. where the sweet sweet center is whatever piece of matter is vibrating. Some layers would have low pressure (troughs), and some layers would have higher pressure (peaks). The amplitude of the wave decreases with distance from the source.

It's the high pressure peaks that cause stimulation in the eardrum, thus commencing the process of perception, which we are absolutely not going to talk about in this post.

You can't characterize the tone as a straight line, no matter how much you want to. Even pure tones are subject to Fourier analysis as Walfin said.

If you continue trying to break the concept down into its constituent parts you're going to continue to miss the mark. You cannot force your idea to be right.

I totally understand the desire to comprehend, plus the mental exercises of abstraction and conceptualization. Your preliminary assumptions are flawed thus this whole thread is continually getting nowhere.
three thumbs up

#### scorpiomover

##### The little professor
We don't hear the tone. We hear the reverberation. IIRC, the ear contains 3 bones, attached to the eardrum. Sounds are collected and reflected into the ear by the ear's outer shape. The eardrum rattles like a paper bag. This is attached to a set of bones, which react to the movement of the eardrum, magnifying the sounds. Then the sounds pass into chambers in the inner ear, where there are between 17,500 and 23,500 hair cells. inner hair cells, where the hairs are suspended in a liquid, and attached to nerves. The more these hairs are made to reverberate by the sounds passing through the liquid, the more the nerves react.

A higher-pitched sound would mean a higher frequency, and consequently the nerve synapses send more messages per second. However, some frequencies are simply too fast for some materials to catch, and others are too slow to be caught. So one requires the right types of hairs for the right tones. We humans only hear a very limited range of tones. Dogs hear tones that we can't.

The greater the amplitude, the more energy in the wave, but with the same frequency. So the synapses fire at the same rate, But the hairs are shaken more violently to cause a wider reverberation, which produces a stronger signal. So too low an amplitude, and you won't hear the sound. Too high, and the hairs can be damaged.

This is almost exactly what the root of this thread is about.
On a side note, I play piano and I always used to hold down the keys without playing them in the upper register and would then play keys in the lower register to allow the keys in the higher register to vibrate and produce sound when I was little.
Resonance. Each material can receive and transmit waves. But certain wavelengths are better suited to the structure of the molecules and how they move together and within the material. This produces a much more efficient transmission of the waves, with very little of the wave's amplitude being lost. As a result, strings of the correct material, length and thickness are chosen, that will resonate well with a certain frequency and a certain tone. If the key is pressed slowly and held down, then there is a very small-amplitude wave that slowly gets weaker as its corresponding wire vibrates slower and slower, until its vibrations are no longer audible. The wire remains taut. So another wave could travel through the air from another wire, and the wire could absorb its energy wave and start vibrating. Since its not its resonance frequency, the sound will be much quieter. Also, resonance effects also can come about, if the frequencies are related, often by one beng a precise multiple of another, which makes the second wave more powerful and thus louder than the other silently-depresssed keys.

Anywho, you understand the question I'm asking, I think. How is it that all of those waves (technically speaking, an infinite amount of waves?) produce only one audible sound?
Waves can pass through each other. An oscillator picks up on the total amplitude at any one point, using systems that are easily fast enough and accurate enough to pick up the entire waveform. When showing multiple sounds, they often show a weird chaotic pattern that displays the cumulative effect of all the waves.

According to physics, the individual waves remain separate. So the different tonal hairs can measure them separately. So instead of a single-track, or an 8-track, our ears have several thousands of tracks, and all their results are cumulative. So they can be added up in a variety of combinations.

Is the sound that we hear even a wave that is produced by plucking the string?
[/quote]Sounds arise from the larynx, which uses muscles to change the volume and tone of the voice. Muscles contract and expand. So they don't just change, but slowly in a smoothly continuous pattern. So such smooth changes in the same frequencies and volumes, can be used to identify a particular group of sounds that could all be coming from the same person. Consistent volume changes can indicate direction and location of the sound waves, and even movement of the speaker, which can further be used to follow the voice. Individual tones are matched to all previously experienced sound recordings, according to how often they were heard, and other factors. From this, patterns emerge. First, the type of speaker, whether bird, lion, tree, or human. Then patterns are matched for phonics. Then they are matched to known words or other audible compete sounds, such as a grunt. From there, possible words are combined to form entire sentences. Usually, the process happens as one is listening, sentence by sentence. If there are gaps, then intuition has to step in and guess what was missing. Tone of voice, applies to the general pitch of the word itself, as if the word was a set of sound waves that had their respective frequencies all doubled or halved at once.

Our brains get the individual waves, with their wave-forms, their frequencies, and their amplitudes. Everything that we think we hear, has to be constructed from that. According to experiments of perceptual psychologists, when you hear the words "Salma Hayek", there is actually a concept neuron fiing off that a particular sub-sequence of waves in the data, matches the concept stored within the cell. There is one for "Jennifer Anniston", one for "Brad Pitt", and another one for when they were a couple and were shown together.

So what we think we hear, is actually not the neural impulses, but a series of concepts played out in a simulation, that have an attached individual sound, and are ordered sequentially. Although there can be many sounds playing simultaneously at equal volume, that doesn't usually happen in what one hears, because then you can't focus on anything and it's all a blur. So when tends to happen, is that in the sim, only a few sounds will have their amplitude raised to be loud, and the rest to sound much quieter, so you can focus.

However, concept neurons are duplex models. They store images and sounds. When those images and sounds are seen and heard later, the concept neuron fires off, and the concept is recalled as well. So when your brain lays out the concept, the signals that represent the sequence of neural impulses that mentally represent the stored sound also fire off, and that is what your conscious receives, so that you get the sounds and their meaning simultaneously, which allows one to make mental associations between the sounds and new meanings, which allows one to learn to hear using cause-and-effect correlations.

When you get a lag between the sounds and their identification and interpretation, it sounds like nothing you've heard of before, and there is usually quite a lag. This is because if the brain could have done it quickly, it would have delayed the sound-play a bit, to allow synchronised transmission of the entire concept to the conscious awareness. When you finally figure out what the sounds are, then suddenly it all makes sense, and it's not bothering you anymore. This is because once is has been correctly identified, the brain can load the programs dealing with that type of sound, and can run them immediately.

#### Montresor

##### Banned
A higher-pitched sound would mean a higher frequency, and consequently the nerve synapses send more messages per second.

Wrong!

Read the thread if you're going to be a smartass and post. I already tried saying that (what you said) and figured out for myself that it is wrong.

The cochlea is tonotopically organized, meaning the frequency of the sound is perceived because it excites only a small area of the cochlea.

The frequency of the impulses translates to the perceived intensity (i.e. amplitude) of the sound, because action potentials can only occur up to a maximum frequency and each impulse is identical.

#### Meer

##### Jermbl
Holy shit you guys are overthinking this. Also, what is the point of this thread?

So, to reiterate again: The pressure oscillation (sine wave) produces a sound (straight line) that splits the sine wave down the x axis with a slope of 0. Yeah, that's definitely what I'm thinking.
Sound is amplitude over time. If you're thinking about a single pure tone like a straight line, you have frequency on the y-axis, not amplitude. If you take your constant sine wave and plot its frequency over time, you get a straight line. Actually, this is what my avatar is, but it is a more complex sound.

#### The Introvert

##### Goose! (Duck, Duck)
Holy shit you guys are overthinking this. Also, what is the point of this thread?
This thread works pretty much how all of my other threads work. I ask a fairly concrete question (or make a fairly concrete statement) and attempt to apply the hodge-podge of answers to everything and anything I can think of. Other people may inject their own opinions, but in the end the thread is mine and only mine.
So, in actuality, the thread could actually be about wavelengths and hearing, or what kind of fish I should eat this Friday. Or both, or neither!

I just like throwing ideas out into the world and letting the birds squabble over it.

#### The Introvert

##### Goose! (Duck, Duck)
The finite, consciousness, must therefore reduce infinite to the finite, a wave to a particle. The whole must be reduced to the average in order to be perceived. Relativity depends upon finite observers, if reality is infinite, then these finite observers must be a result of limited perception.
By the mechanisms found earlier in the thread.
If everything were one, then it could not be observed. Consciousness, therefore, is the restriction of all possibility to one. That's not to say that all possibility is not occurring simultaneously, merely that my and your perspectives are one of infinite perspectives which make up a much larger infinite.
You might say... an infinitely large infinite