SCALE TYPES
Non12-Tone Equal Tempered
In this series, the listener is exposed to different types of equal-tempered scales. Our western chromatic or 12-tone equal tempered scale is mathematically derived. Non-12 equal tempered scales are also mathematically derived, but their number of notes per octave is different which results in audible distances/differences between neighboring notes, and this creates the character of the scale.
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Currently, there are four (non-12 equal) instruments that have been made:
5-tone equal, 7-tone equal, 8-tone equal, and 9-tone equal.
Common Details that Apply to All Instruments
Range: Tenor C (C3) to Treble C (C5)
Bars: African Padauk
Resonator: Poplar
Finish: Semi-gloss clear coat (waterbase)
5-Tone Equal Tempered
This instrument is available for rental from
LA Percussion Rentals
Model C311-ET5 Specification
2-Octave / 5-tone equal-tempered scale
No. of Notes: 11
Dimensions: W: 30 x D: 14" x H:14-1/2"
Weight: 14.5lbs.
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Scale Technical Definition: 5-Tone Equal
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Octave determination: 5th root of 2 = a factor of 1.14869835
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Number of notes per octave = 5
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Number of cents per octave = 1200
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Number of cents between notes = 240 (1200/5)
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Scale Character
5-Tone Equal has notes that relate to 12-Tone Equal. Scale character can be heard when two note intervals with x no. of notes in between.
This instrument is available for rental from
LA Percussion Rentals
7-Tone Equal Tempered
Model C311-ET7 Specification
2-Octave / 7-tone equal-tempered scale
No. of Notes: 15
Dimensions: W: 40" x D: 14" x H: 14-1/2"
Weight: 18.5lbs.
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Scale Technical Definition: 7-Tone Equal
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Octave determination: 7th root of 2 = a factor of 1.1040895
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Number of notes per octave = 7
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Number of cents per octave = 1200
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Number of cents between notes = 171.43 (1200/7)
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Scale Character
7-Tone Equal has no notes that relate to 12-Tone Equal. Scale character can be heard when two note intervals with x no. of notes in between.
This instrument is available for rental from
LA Percussion Rentals
8-Tone Equal Tempered
Model C317-ET8 Specification
2-Octave / 8-tone equal-tempered scale
No. of Notes: 17
Dimensions: W: 44-1/2" x D: 14" x H: 14-1/2"
Weight: 19.5lbs.
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Scale Technical Definition: 8-Tone Equal
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Octave determination: 8th root of 2 = a factor of 1.090507733
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Number of notes per octave = 8
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Number of cents per octave = 1200
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Number of cents between notes = 150 (1200/8)
Scale Character
The 8-tone equal is based on the 12-tone equal's minor 3rds or diminished scale which consists of four tones: C, D#, F#, and A or notes 1, 3, 5, and 7 (as shown in the photo above). If we move up one step and only play notes 2, 4, 6, and 8, then the second diminished scale is revealed. Both scales are demonstrated in the audio example -->.
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When the 1, 3, 5, 7 and 2, 4, 6, 8 notes are combined in their numerical order as 1, 2, 3, 4, 5, 6, 7, 8, then the half-diminished equal scale is more easily understood as demonstrated in the first audio example above.
This instrument is available for rental from
LA Percussion Rentals
9-Tone Equal Tempered
Model C319-ET9 Specification
2-Octave / 9-tone equal-tempered scale
No. of Notes: 19
Dimensions: W: 49-1/4" x D: 14" x H: 14-1/2"
Weight: 19.5lbs.
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Scale Technical Definition: 9-Tone Equal
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Octave determination: 9th root of 2 = a factor of 1.08005974
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Number of notes per octave = 9
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Number of cents per octave = 1200
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Number of cents between notes = 133.333333 (1200/9)
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Scale Character
The 9-tone equal is based on the 12-tone equal's major 3rds or augmented scale which consists of three tones: C, E, and G# or notes 1-4-7 (as shown in the photo above). This would be considered the first 3rd.
Second 3rd: If we move up one step and only play notes 2, 5, 8, then the second augmented scale is revealed.
Third 3rd: Finally, if we move up one more step and only play notes 3, 6, 9, then the third augmented scale is revealed.
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The top audio example is how the 9-tone scale sounds when these three groups are combined.
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The two audio examples on the bottom provide the flavor of a two-note interval - one in the high octave, one in the low octave.
​NOTE:
It is interesting to note that the 12-Tone Equal Tempered scale actually contains five equal-tempered scales within it. This is easily determined because the number 12 can be equally divided in five ways, as follows:
1. [12/6] = 2-Tone Equal (based on the flatted 5th or Tritone: C, F#, C)
2. [12/4] = 3 Tone Equal (based on major 3rds: C, E, G#, C)
3. [12/3] = 4-Tone Equal (based on minor 3rds: C, D#, F#, A, C)
4. [12/2] = 6-Tone Equal (based on the 2nd or whole-tone steps: C, D, E, F#, G#, A#, C)
5. [12/1] = 12-Tone Equal (based on half or chromatic steps: C, C#, D, D#, E, F, F#, G, G#, A, A#, B, C)
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43-Tone Equal Tempered
This instrument is available for rental from
LA Percussion Rentals
Harry Partch "Boo" Recreation (2017)
1-1/2-Octave / 43-tones per octave equal-tempered scale
No. of Notes: 64
Dimensions: W: 101" x H: 60.25" x D: 35"
Weight: TBD
Year of Construction: 2017
Client: John Schneider (Partch Ensemble)
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Scale Technical Definition: 43-Tone Equal
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Octave determination: 43rd root of 2 = a factor of 1.0162503
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Number of notes per octave = 43
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Number of cents per octave = 1200
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Number of cents between notes = 27.9 (1200/43)