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Amplitude Of Single Tone Sound Wave = "Loudness"?
Hello,
Given a single tone sound wave: x(t) = A * sin( 2 * pi * freq * t ), what does the 'A' actually represent? Peak Intensity? Intensity Level? Peak Amplitude Pressure? What is adding to my confusion is this link: http://www.jhu.edu/~signals/listen-new/listen-newindex.htm
I am using a Matlab clone called Octave to generate wave files. These wav files contain single tone sounds. I generate the single tone with the following command:
tone1 = transpose( cPeak1 * sin( 2 * pi * fx * t ) );
I expect the variable cPeak1 to affect the "loudness" of the tone. If I increase cPeak the tone will sound louder, if I decrease cPeak it will sound softer. I have been assuming that my variable cPeak is the Intensity.
But changing the value of cPeak does not affect the *wave* files I am generating. When I vary cPeak and plot the tones, I can see the change in amplitude. When I vary cPeak and generate wave files, the files all sound the same (in terms of loudness).
Here is a pastebin of the Octave 'm' file I am using to create the tones...I'm not sure if it will work with Matlab.
http://pastebin.com/dbKmnVwU
Thanks!
Hello,
Given a single tone sound wave: x(t) = A * sin( 2 * pi * freq * t ), what does the 'A' actually represent? Peak Intensity? Intensity Level? Peak Amplitude Pressure? What is adding to my confusion is this link: http://www.jhu.edu/~signals/listen-new/listen-newindex.htm
Why a^0.6 and not 'a' and why proportional?The perceived loudness of a pure tone is proportional to a^0.6
I am using a Matlab clone called Octave to generate wave files. These wav files contain single tone sounds. I generate the single tone with the following command:
tone1 = transpose( cPeak1 * sin( 2 * pi * fx * t ) );
I expect the variable cPeak1 to affect the "loudness" of the tone. If I increase cPeak the tone will sound louder, if I decrease cPeak it will sound softer. I have been assuming that my variable cPeak is the Intensity.
Code:
Single tone sound wave intensity: [b]I = P^2 / 2 * rho * v[/b]
I: Intensity in watts/m^2
P: Pressure amplitude in Pa
rho * v : Characteristic impedance of the air
But changing the value of cPeak does not affect the *wave* files I am generating. When I vary cPeak and plot the tones, I can see the change in amplitude. When I vary cPeak and generate wave files, the files all sound the same (in terms of loudness).
Here is a pastebin of the Octave 'm' file I am using to create the tones...I'm not sure if it will work with Matlab.
http://pastebin.com/dbKmnVwU
Thanks!
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