A pure tone is a tone with a sinusoidal waveshape.

A sine wave is characterized by its frequency — the number of cycles per second, or its wavelength — the distance the waveform travels through its medium within a period, and the amplitude — the size of each cycle. A pure tone has the unique property that its waveshape and sound are changed only in amplitude and phase by linear acoustic systems.

History

A pure sine wave is an artificial sound. Hermann von Helmholtz is credited as the first creator of a sine wave with the 'Helmholtz siren', a mechanical device that sends compressed air through holes in a rotating plate. This is presumably the closest thing to a sine wave that was heard before the invention of electronic oscillators.

Acoustic properties

Sinewaves are generally uncomfortable to the ear, and are more damaging to the ear than other noises at equal volumes. Sinewaves are often more difficult than other sounds at placing the location of its source- they seem to ‘fill the room’.

From Wikipedia under the GNU Free Documentation License
Thu Jan 14 18:15:53 2010

effect pure tone jpg
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Effect of differential between pure tone and background

The Tune Chic is Sandy Connolly who was originally trained in
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The Tune Chic is Sandy Connolly who was originally trained in
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The Tune Chic is Sandy Connolly who was originally trained in the depths of the Southland Her parents sent her to school to study classically but she had the fortunate opportunity in 1986 to hear Bonnie Raitt in an intimate concert on Martha s Vineyard There she found her musical calling the blues and rock n roll Throwing dirt on her pure tone and getting all gravely and groovy was way more fun and way more people liked to listen to it Soon after she began guitar lessons with the late Sal Salvador well known jazz guitarist in New England and studied for three years getting her groove down She now joins forces with lots of musicians in the New Haven area most notably lead guitar player Johnny Memphis bass player Eric Kuhn and drummer Rick Haddad for The Tune Chic Rock Band as well as The Tall Boys Blues Band

A Pure Tone Logo2 BUP jpg
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Click to enlarge Kit includes

From Yahoo Image Search: "Pure tone"
Tue Sep 15 18:05:51 2009

North River Blues Festival packs bigg... - The Patriot Ledger
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North River Blues Festival packs biggest crowd ever

The Patriot Ledger

He's one of the nicest guys you'll ever meet, and musically, he's got a tone to die for. He is my favorite, the BB King of harmonica. ...
Top handbag stories for Fall 2009 par... - Examiner.com
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Top handbag stories for Fall 2009 part three

Examiner.com

Fendi set the tone with its aptly named Peek-a-Boo line. This version incorporates two top handbag stories simultaneously - red and l'animal! ...



and more »
Makeup That Does More - San Francisco Chronicle
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Makeup That Does More

San Francisco Chronicle

Try Jane Be Pure Mineral Skin Perfecting Foundation SPF 30 ($5.49, drugstores) and Shiseido Sun Protection Liquid Foundation SPF 42 PA+++ ($33.50, ...

From Google News Search: "Pure tone"
Wed Aug 26 02:14:00 2009

How can I make my skin tone more paler?
Q. I have little bit tanned face and would like to get my face to be pure pale is there any way how to achieve it???
Asked by Cube - Wed Jul 16 17:35:23 2008 - - 14 Answers - 0 Comments

A. i LOVE pale skin and try to be as pale as possible i think tan is uugly anyway stay inside, or wear makeup
Answered by Macabre - Wed Jul 16 18:10:47 2008

Do you think some political commentators like Limbaugh, Olbermann and Savage should tone down the hate?
Q. As a con I have always thought that, although many conservative radio personalities make some good points, they are too disrepectfull of those they criticize. Keith Olbermann spends his entire show condemning every single republican as being pure evil. I think that it is too easy to sit around and listen to someone bash the other side just to make you feel good about yourself.
Asked by lend322 - Tue Jun 10 01:05:36 2008 - - 12 Answers - 0 Comments

A. I am a Democrat, but I agree with you, some people go just too far.
Answered by Angel - Tue Jun 10 01:12:21 2008

Does the word "tone" mean two different things when you are talking about guitar and bass?
Q. For bass it seems more like how the body is built, and the growl that that gives. For guitar its more about pure sound.
Asked by card house - Fri Mar 13 21:20:04 2009 - - 2 Answers - 0 Comments

From Yahoo Answer Search: "Pure tone"
Fri Jan 22 00:27:47 2010

Mastering Vs Biology | PublicSpacesLab
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Mastering Vs Biology | PublicSpacesLab

puretone

hu, 13 Aug 2009 11:20:29 GM

Pure. -. Tone. . Posted August 13, 2009 at 4:26 PM. Thanks Doyle, and you're right. Sometimes sound is given a raw deal compared to visual. Take call of duty world at war . Looks fantastic, plays fantastic, but the sound is awful. ...

Billy Cobham live remaster - PureTone Mastering - PureToneMastering
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Billy Cobham live remaster - PureTone Mastering - PureToneMastering

puretonemastering

hu, 30 Jul 2009 11:09:51 GM

Hi guys. i worked this piece for something to do.as you will hear, the source was pretty flat. so this was an exercise in inflation :) .the source is tape damaged. it wanders slightly here and there, and it sounds very saturated in ...

theta ( pure tone remaster)
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theta ( pure tone remaster)

admin

Wed, 05 Aug 2009 19:35:55 GM

once more, something a little special, @pure_tone has taken my latest ambient work, theta and his talented ears has made my little piece sparkle. consider following him on twitter (@pure_tone) if you care about purist audio. ...

From Google Blog Search: "Pure tone"
Fri Oct 16 09:55:38 2009