Difference between revisions of "Sound for Interaction class 4"

esse quam videri
Jump to: navigation, search
(Homework)
 
(10 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
[[Category:Sound for Interaction]]
 
[[Category:Sound for Interaction]]
  
== Speed of Sound ==
+
{{Template:Speed of Sound}}
  
 +
{{Template:Frequency/Period}}
  
The [http://en.wikipedia.org/wiki/Speed_of_sound Speed of sound] is measured in meters per second.The speed of sound is affected by several factors:  temperature, humidity, and elasticity.
+
{{Template:Resonance}}
  
SOS ~ 344 m/s or 1130 f/s
+
{{Template:Wavelength}}
  
NOTE: for class we will assume the speed of sound in air @ 20 degrees Celsius an 75% humidity is 344m/s
+
{{Template:Perception of Amplitude and Frequency}}
  
Speed of sound Calculator http://www.measure.demon.co.uk/Acoustics_Software/speed.html
+
{{Template:Interference and Beats}}
  
== Frequency/Period ==
+
{{Template:Looping and Rhythm}}
  
  
Sound is a periodic event. This means that there is a fixed amount of time between different events.The Frequency component of a sound wave affects the pitch of the sound.
+
[[Sound for Interaction Loops]]
  
Frequency is measured in Hertz (cycles per second)
+
==Homework==
 
 
Period = 1 / Frequency in HzT = 1/f
 
 
 
Frequency = 1/ Period  f = 1/T
 
  
Different types of frequency components periodic/ aperiodic
+
SuperFresh DJ MC Down Guy
  
It is assumed the humans can hear frequencies from 20Hz to 20,000 Hz.
+
Create three loops of one song and string them together to 'remix a song'.
 
 
20-20KHz Sweep 
 
:http://iam.colum.edu/sound/media/sweep20-20.wav 41kb,16 bit 3.7megs
 
 
 
==Resonance==
 
[http://en.wikipedia.org/wiki/Resonance Resonance]
 
 
 
[http://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge Tacoma Narrows Bridge]<br>
 
[[Image:MTD2newtacoma.jpg]]<br>
 
Movie1 http://interactive.colum.edu/sound/media/tacoma3.avi<br>
 
Movie2 http://interactive.colum.edu/sound/media/tacoma4.avi<br>
 
 
 
=Wavelength=
 
 
 
Wavelength is measured in distance (ft. of m)
 
 
 
The actual physical length of a single cycle of a wave
 
 
 
Wavelength = speed of sound / Frequency in Hz
 
:λ = SOS/f
 
 
 
wavelength = speed of sound * period
 
:λ = SOS*T
 
 
 
The wavelength of a sound wave varies greatly with the frequency of the wave. A 20 kHz wave has a wavelength of 1.72 (0.7 in)cm while a 20 Hz wave has a wavelength of 17.2 m (~56 ft.).
 
 
 
Examples http://iam.colum.edu/MTD2/lectures/week1_examples.htm<br>
 
 
 
==Perception of Amplitude and Frequency==
 
 
 
Humans do not hear all frequencies equally. We perceive different frequencies with equal energy to have different amplitudes. The Fletcher Munson Curves show the phons scale, how amplitude is perceived by frequency
 
 
 
Fletcher Munson Curves 1
 
http://arts.ucsc.edu/EMS/Music/tech_background/TE-02/AcNumbers/AcNumbers.html
 
 
 
Fletcher Munson Curves 2
 
http://www.allchurchsound.com/ACS/edart/fmelc.html
 
 
 
Fletcher Munson Curves 3
 
http://hyperphysics.phy-astr.gsu.edu/hbase/sound/eqloud.html
 
 
 
==Behaviour of sound waves==
 
* Interference and Beats
 
 
 
==Music Theory Rhythm==
 
Music Theory time and meter
 
Time
 
 
 
* Time Signatures - [http://en.wikipedia.org/wiki/Time_signature wikipedia]  examples -ie only sorry
 
* Beats and measures
 
* [http://www.dolmetsch.com/musictheory4.htm#anatomy Music Theory Online Lesson 4 Time Signatures]
 
* [http://www.teoria.com/reference/index.htm Online Music Theory Reference]
 
 
 
Poly Rhythms [http://www.vai.com/LittleBlackDots/tempomental.html vai.com]
 
 
 
==Looping in Sound Forge==
 
*Turn on Loop
 
*Mark ins and outs
 
 
 
==Homework==
 
Create three loops of one song and string them together.
 

Latest revision as of 18:42, 23 July 2007

Speed of Sound

The Speed of sound is measured in meters per second.The speed of sound is affected by several factors: temperature, humidity, and elasticity.

SOS ~ 344 m/s or 1130 f/s

NOTE: for class we will assume the speed of sound in air @ 20 degrees Celsius an 75% humidity is 344m/s

Speed of sound Calculator http://www.measure.demon.co.uk/Acoustics_Software/speed.html

Frequency/Period

Sound is a periodic event. This means that there is a fixed amount of time between different events.The Frequency component of a sound wave affects the pitch of the sound.

Frequency if the measure of how many cycles a wave complete per second.

Frequency (f) is measures in Hertz

Period (T) in the inverse of infrequency is is measured in seconds

Frequency = Cycles/Second Period = Seconds/Cycle

f = 1/T T = 1/f

Different types of frequency components periodic / aperiodic.

Periodic

sound that has a measurable frequency

Aperiodic

sound that is mostly random

It is assumed the humans can hear frequencies from 20Hz to 20,000 Hz.

20-20KHz Sweep

http://iam.colum.edu/sound/media/sweep20-20.wav 41kb,16 bit 3.7megs

Resonance

Resonance

Wavelength

Wavelength is measured in distance (ft. of m)

The actual physical length of a single cycle of a wave

Wavelength = speed of sound / Frequency in Hz

λ = SOS/f

wavelength = speed of sound * period

λ = SOS*T

The wavelength of a sound wave varies greatly with the frequency of the wave. A 20 kHz wave has a wavelength of 1.72 (0.7 in)cm while a 20 Hz wave has a wavelength of 17.2 m (~56 ft.).

Examples http://iam.colum.edu/MTD2/lectures/week1_examples.htm

Perception of Amplitude and Frequency

Humans do not hear all frequencies equally. We perceive different frequencies with equal energy to have different amplitudes. The Fletcher Munson Curves show the phons scale, how amplitude is perceived by frequency

Fletcher Munson Curves 1 http://arts.ucsc.edu/EMS/Music/tech_background/TE-02/AcNumbers/AcNumbers.html

Fletcher Munson Curves 2 http://www.allchurchsound.com/ACS/edart/fmelc.html

Fletcher Munson Curves 3 http://hyperphysics.phy-astr.gsu.edu/hbase/sound/eqloud.html

Interference and Beats

adding sound waves

  • Interference and Beats

http://www.school-for-champions.com/science/soundbeat.htm

Difference between two notes is called interval

Music Theory Rhythm

Music Theory time and meter Time

Poly Rhythms vai.com

Looping in Sound Forge

  • Turn on Loop
  • Mark ins and outs


Sound for Interaction Loops

Homework

SuperFresh DJ MC Down Guy

Create three loops of one song and string them together to 'remix a song'.