Octave Frequency Sweep, Consonance & Dissonance - A220 Sine Wave
A frequency sweep of two tones (sine waves) starting at unison and rising to the octave. The base tone is the note 'A' 220 Hz with the rising note sweeping from 220 Hz up to 440 Hz. The twelve semitones that the sweep reaches are indicated with a red line for each note in the chromatic scale.
A graph showing the Blackman Spectral Analysis illustrates the overtone interference created by the interaction of the two notes. Pythagorean ratios are listed at the top of the graph, indicating zones of low tension (consonance) where the overtones lock into ratios of low whole numbers.
According to one theory of harmony, the levels of tension listed from highest to lowest can be grouped as follows:
Perfect dissonance: minor second, tritone, and major seventh
Mediocre dissonance: major second and minor sixth
Imperfect dissonance: major sixth and minor seventh
Imperfect consonance: minor and major third
Mediocre consonance: fourth and fifth
Perfect consonance: unison and octave
The x-axis of the graph indicates seconds, and is off roughly by a factor of two as the duration of the audio sweep has been doubled.
---------[edit-2016Jun30]:
...the website where I had gotten this image:
http://www.interferencetheory.com/Excerpts/page11/page15/page15.html
Richard Merrick's books look like they might be amazing reads.
And here is another person who I think does an excellent job of grasping a better understanding of music:
StephenMalinowski.com
This clip from his 1996 documentary explains the basics of music intervals as a 'locking' of overtones:
https://www.youtube.com/watch?v=yq0iMqQpxbA&t=19m
---------
Recommended DNews video to help answer the question,
"Where did music come from?":
http://www.youtube.com/watch?v=5_3OS0nY3WQ
(gives example from nature for octaves, perfect fourths, etc)
To get a better appreciation for the limitations of the Equal Temperament Chromatic Scale that is common in Western music and popular instruments like the piano and guitar, you can check out recent microtones musical instrument inventions such as the...
- Microtonal Keyboard, and the
- Microtonal Guitar
...that enable Pythagorean ratios and Just Intonation.
Here's one Microtonal Keyboard demo video by Aaron Wolf:
http://www.youtube.com/watch?v=APtJsaPxNgo
Here's a Microtonal Guitar demo video by Tolgahan Çoğulu:
http://www.youtube.com/watch?v=MYK_PF9WTRE
http://www.youtube.com/watch?v=yhdpsuXtewY
A graph showing the Blackman Spectral Analysis illustrates the overtone interference created by the interaction of the two notes. Pythagorean ratios are listed at the top of the graph, indicating zones of low tension (consonance) where the overtones lock into ratios of low whole numbers.
According to one theory of harmony, the levels of tension listed from highest to lowest can be grouped as follows:
Perfect dissonance: minor second, tritone, and major seventh
Mediocre dissonance: major second and minor sixth
Imperfect dissonance: major sixth and minor seventh
Imperfect consonance: minor and major third
Mediocre consonance: fourth and fifth
Perfect consonance: unison and octave
The x-axis of the graph indicates seconds, and is off roughly by a factor of two as the duration of the audio sweep has been doubled.
---------[edit-2016Jun30]:
...the website where I had gotten this image:
http://www.interferencetheory.com/Excerpts/page11/page15/page15.html
Richard Merrick's books look like they might be amazing reads.
And here is another person who I think does an excellent job of grasping a better understanding of music:
StephenMalinowski.com
This clip from his 1996 documentary explains the basics of music intervals as a 'locking' of overtones:
https://www.youtube.com/watch?v=yq0iMqQpxbA&t=19m
---------
Recommended DNews video to help answer the question,
"Where did music come from?":
http://www.youtube.com/watch?v=5_3OS0nY3WQ
(gives example from nature for octaves, perfect fourths, etc)
To get a better appreciation for the limitations of the Equal Temperament Chromatic Scale that is common in Western music and popular instruments like the piano and guitar, you can check out recent microtones musical instrument inventions such as the...
- Microtonal Keyboard, and the
- Microtonal Guitar
...that enable Pythagorean ratios and Just Intonation.
Here's one Microtonal Keyboard demo video by Aaron Wolf:
http://www.youtube.com/watch?v=APtJsaPxNgo
Here's a Microtonal Guitar demo video by Tolgahan Çoğulu:
http://www.youtube.com/watch?v=MYK_PF9WTRE
http://www.youtube.com/watch?v=yhdpsuXtewY
