Sound is probably much simpler than most people think it is. It is caused by something moving back and forth.

Acoustic sounds

When you pluck a string, it vibrates. The vibration causes the pressure of the air to change, which in turn makes your ear drum vibrate at the same frequency (the same speed) as the string. The same thing happens when you hit a drum: it moves back and forth, which moves your ear drum back and forth. Human ears can pick up any sound between about 20Hz and 20kHz, meaning they can pick up any physical vibration that repeats between roughly twenty and twenty thousand times a second.

Resonance

Plucking a string gets it to vibrate, but it isn't the only way. The frequency it vibrates at is known as its natural frequency. You could instead play the same note with a different musical instrument, right next to the string, which would also cause it to vibrate. Everything has a natural frequency which causes it to vibrate when something close to it is already vibrating at the same frequency. This isn't necessarily a good thing, and it's the reason why opera singers can break glass and why wind can make bridges collapse. It is also the reason why certain frequencies are boosted more than others by the hollow body of an acoustic guitar.

Electric sounds

Artificial sounds and recordings are usually played using electric loudspeakers (a notable exception being the acoustic phonograph). A speaker contains a permanent magnet, an electromagnet and a cone-shaped surface. When an electric signal is fed through the speaker, the strength of the electromagnet increases and decreases, making it move away from the permanent magnet, then back towards it. This causes the cone attached to the electromagnet to move back and forth. As it can produce complex, non-repeating movement, it can replicate pretty much any sound, making it very versatile.

Digitally stored sounds

Computers and consumer electronics (such as CD players) take electric sounds one stage further. The position the speaker cone should be in at any given time is stored as a number, which the device keeps track of (in the case of CDs, it is a sixteen bit number, meaning sixteen 1s and 0s make up a number between 0 and 65535, which is how many subtle distances the magnets can be from each other). By reading the series of numbers in the right order, and moving the speaker to the appropriate position each time, the device can reproduce a very close approximation of the original sound (with CD players, the speaker position is updated 44100 times every second). This process is known as pulse code modulation, or PCM for short. While records and tape recordings can already reproduce sounds quite accurately, PCM enables recordings to be easily stored and shared. This is good news for people who collect recordings of sounds, such as music or audiobooks. It's also bad news for people who own the copyright on such recordings, if their licenses don't permit such sharing. This problem affects all media that can be digitised, however, not just sound. The various attempts at preventing the unauthorised copying of such materials are known as digital rights management.

The technical side of sounds

Sound is a type of waveform. This means that you can draw a sound as a graph, with the x-axis (the horizontal one) representing time and the y-axis (the vertical one) representing the position of whatever's making the sound. It also means that any sound can be translated into many sine waves of different frequencies and amplitudes. See Fourier analysis and Fourier synthesis for more details about how to break sounds down into their component sine waves, or how to build up sounds from these building blocks. Pipe organs have long been making musical timbres this way.

So there you have it. Sound can be as simple as something moving back and forth very quickly, or as complex as Fourier transforms. Just be careful not to accidently break your window.

In the fields of logic, rhetoric, and philosophy, a sound argument is one that is both correctly formed and contains all true premises.

An argument with a correct form is called valid. However, it is possible to have a valid argument that is not sound.

A valid but not sound argument:

1. I am a doctor.
2. All doctors are smart.
--------------------------
3. Therefore, I am smart.

The conclusion follows from the statements, and if statement 1 and 2 were true, then this argument would be sound. However (at least) statement 1 is false. Therefore, this argument is unsound. It should be noted this argument is both valid and the conclusion is true. However, no matter how obvious 3 may be, I have not yet proven it through means of logical argument.

Ear and sound
do not block each other
and so there is no sound
and nothing said.

Dogen zenji
translated by
Yasuda Joshu Dainen roshi and Anzan Hoshin sensei

ON IN oto (sound)

ASCII Art Representation:

             #
              #    #
        #############
           #    ##
            #  #     #
      #################
 
          #########
          #       #
          #########
          #       #
          #########
         
        

Character Etymology:

Once written as a pictograph of a face with a mouth to create the old character for speak. Later, a tongue was added to show greater vocalization, i.e. to shout or to sing. This led to just the present meaning of sound.

A listing of all on-yomi and kun-yomi readings:

on-yomi: ON IN
kun-yomi: oto ne

Nanori Readings:

Nanori: o to

English Definitions:

1. ON: sound, noise, pronunciation.
2. IN: sound or tone.
3. oto: sound, noise, roar, or fame.
4. ne: sound, tone, note, voice, or chirping.

Unicode Encoded Version:

音

Unicode Encoded Compound Examples:

音楽 (ongaku): music.
発音 (hatsuon): pronunciation.
音訓 (onkun): referring to the pronunciation of Japanese's Chinese characters. See: on-yomi and kun-yomi.

  Previous: king  |  Japanese Kanji  |  Next: below

Sound (?), n. [AS. sund a swimming, akin to E. swim. See Swim.]

The air bladder of a fish; as, cod sounds are an esteemed article of food.

 

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Sound, n. Zool.

A cuttlefish.

[Obs.]

Ainsworth.

 

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Sound, a. [Compar. Sounder (?); superl. Soundest.] [OE. sound, AS. sund; akin to D. gezond, G. gesund, OHG. gisunt, Dan. & Sw. sund, and perhaps to L. sanus. Cf. Sane.]

1.

Whole; unbroken; unharmed; free from flaw, defect, or decay; perfect of the kind; as, sound timber; sound fruit; a sound tooth; a sound ship.

2.

Healthy; not diseased; not being in a morbid state; -- said of body or mind; as, a sound body; a sound constitution; a sound understanding.

3.

Firm; strong; safe.

The brasswork here, how rich it is in beams,
And how, besides, it makes the whole house sound.
Chapman.

4.

Free from error; correct; right; honest; true; faithful; orthodox; -- said of persons; as, a sound lawyer; a sound thinker.

Do not I know you a favorer
Of this new seat? Ye are nor sound.
Shak.

5.

Founded in truth or right; supported by justice; not to be overthrown on refuted; not fallacious; as, sound argument or reasoning; a sound objection; sound doctrine; sound principles.

Hold fast the form of sound words, which thou hast heard of me.
2 Tim. i. 13.

6.

heavy; laid on with force; as, a sound beating.

7.

Undisturbed; deep; profound; as, sound sleep.

8.

Founded in law; legal; valid; not defective; as, a sound title to land.

⇒ Sound is sometimes used in the formation of self-explaining compounds; as, sound-headed, sound-hearted, sound-timbered, etc.

Sound currency Com., a currency whose actual value is the same as its nominal value; a currency which does not deteriorate or depreciate or fluctuate in comparision with the standard of values.

 

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Sound, adv.

Soundly.

So sound he slept that naught might him awake.
Spenser.

 

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Sound, n. [AS. sund a narrow sea or strait; akin to Icel., Sw., Dan. & G. sund, probably so named because it could be swum across. See Swim.] Geog.

A narrow passage of water, or a strait between the mainland and an island; also, a strait connecting two seas, or connecting a sea or lake with the ocean; as, the Sound between the Baltic and the german Ocean; Long Island Sound.

The Sound of Denmark, where ships pay toll.
Camden.

Sound dues, tolls formerly imposed by Denmark on vessels passing through the Baltic Sound.

 

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Sound, v. t. [imp. & p. p. Sounded; p. pr. & vb. n. Sounding.] [F. sonder; cf. AS. sundgyrd a sounding rod, sundline a sounding line (see Sound a narrow passage of water).]

1.

To measure the depth of; to fathom; especially, to ascertain the depth of by means of a line and plummet.

2.

Fig.: To ascertain, or try to ascertain, the thoughts, motives, and purposes of (a person); to examine; to try; to test; to probe.

I was in jest,
And by that offer meant to sound your breast.
Dryden.

I've sounded my Numidians man by man.
Addison.

3. Med.

To explore, as the bladder or urethra, with a sound; to examine with a sound; also, to examine by auscultation or percussion; as, to sound a patient.

 

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Sound (?), v. i.

To ascertain the depth of water with a sounding line or other device.

I sound as a shipman soundeth in the sea with his plummet to know the depth of sea.
Palsgrave.

 

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Sound, n. [F. sonde. See Sound to fathom.] Med.

Any elongated instrument or probe, usually metallic, by which cavities of the body are sounded or explored, especially the bladder for stone, or the urethra for a stricture.

 

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Sound, n. [OE. soun, OF. son, sun, F. son, fr. L. sonus akin to Skr. svana sound, svan to sound, and perh. to E. swan. Cf. Assonant, Consonant, Person, Sonata, Sonnet, Sonorous, Swan.]

1.

The peceived object occasioned by the impulse or vibration of a material substance affecting the ear; a sensation or perception of the mind received through the ear, and produced by the impulse or vibration of the air or other medium with which the ear is in contact; the effect of an impression made on the organs of hearing by an impulse or vibration of the air caused by a collision of bodies, or by other means; noise; report; as, the sound of a drum; the sound of the human voice; a horrid sound; a charming sound; a sharp, high, or shrill sound.

The warlike sound
Of trumpets loud and clarions.
Milton.

2.

The occasion of sound; the impulse or vibration which would occasion sound to a percipient if present with unimpaired; hence, the theory of vibrations in elastic media such cause sound; as, a treatise on sound.

⇒ In this sense, sounds are spoken of as audible and inaudible.

3.

Noise without signification; empty noise; noise and nothing else.

Sense and not sound . . . must be the principle.
Locke.

Sound boarding, boards for holding pugging, placed in partitions of under floors in order to deaden sounds. -- Sound bow, in a series of transverse sections of a bell, that segment against which the clapper strikes, being the part which is most efficacious in producing the sound. See Illust. of Bell. -- Sound post. Mus. See Sounding post, under Sounding.

 

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Sound, v. i. [OE. sounen, sownen, OF. soner, suner, F. sonner, from L. sonare. See Sound a noise.]

1.

To make a noise; to utter a voice; to make an impulse of the air that shall strike the organs of hearing with a perceptible effect.

"And first taught speaking trumpets how to sound."

Dryden.

How silver-sweet sound lovers' tongues!
Shak.

2.

To be conveyed in sound; to be spread or published; to convey intelligence by sound.

From you sounded out the word of the Lord.
1 Thess. i. 8.

3.

To make or convey a certain impression, or to have a certain import, when heard; hence, to seem; to appear; as, this reproof sounds harsh; the story sounds like an invention.

Good sir, why do you start, and seem to fear
Things that do sound so fair?
Shak.

To sound in ∨ into, to tend to; to partake of the nature of; to be consonant with. [Obs., except in the phrase To sound in damages, below.]

Soun[d]ing in moral virtue was his speech.
Chaucer.

-- To sound in damages Law, to have the essential quality of damages. This is said of an action brought, not for the recovery of a specific thing, as replevin, etc., but for damages only, as trespass, and the like.

 

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Sound, v. t.

1.

To causse to make a noise; to play on; as, to sound a trumpet or a horn.

A bagpipe well could he play and soun[d].
Chaucer.

2.

To cause to exit as a sound; as, to sound a note with the voice, or on an instrument.

3.

To order, direct, indicate, or proclain by a sound, or sounds; to give a signal for by a certain sound; as, to sound a retreat; to sound a parley.

The clock sounded the hour of noon.
G. H. Lewes.

4.

To celebrate or honor by sounds; to cause to be reported; to publish or proclaim; as, to sound the praises of fame of a great man or a great exploit.

5.

To examine the condition of (anything) by causing the same to emit sounds and noting their character; as, to sound a piece of timber; to sound a vase; to sound the lungs of a patient.

6.

To signify; to import; to denote.

[Obs.]

Milton.

Soun[d]ing alway the increase of his winning.
Chaucer.

 

© Webster 1913.