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'''88-cent equal tuning''' uses equal steps of 88 cents each. It is equivalent to 13.6364edo, and is a subset of [[150edo]] (every eleventh step). | |||
==Theory== | ==Theory== | ||
88 cent [[Equal|equal | 88-cent [[Equal-step tuning|equal tuning]] uses 88 cents, or 11\150 of an octave, to generate a [[nonoctave]] rank one scale. Since 88 cents is an excellent generator for [[Tetracot_family|octacot temperament]], it can be viewed as the generator chain of octacot, stripped of octaves. However viewed, octacot and 88-cent equal tuning are very closely related, and the chords of 88-cent tuning are listed on the page [[Chords_of_octacot|chords of octacot]]. From this it may be seen that octacot, and hence 88 cents tuning, share an abundance of [[Dyadic_chord|essentially tempered chords]]. | ||
Eight steps of 88 cents gives 704 cents, two cents sharp of 3/2, and eighteen gives 1584 cents, two cents flat of 5/2. Taken together this tells us that (5/2)^4/(3/2)^9 = 20000/19683, the minimal diesis or tetracot comma, must be being tempered out. Eleven steps of 88 cents gives 968 cents, less than a cent flat of 7/4, and this tells us that (7/4)^8/(3/2)^11 = 5764801/5668704 must be tempered out also. Taking this, multiplying it by the tetracot comma and taking the fourth root yields 245/243, which therefore must be tempered out also. The tetracot comma and 245/243 taken together define 7-limit octacot. | Eight steps of 88 cents gives 704 cents, two cents sharp of 3/2, and eighteen gives 1584 cents, two cents flat of 5/2. Taken together this tells us that (5/2)^4/(3/2)^9 = 20000/19683, the minimal diesis or tetracot comma, must be being tempered out. Eleven steps of 88 cents gives 968 cents, less than a cent flat of 7/4, and this tells us that (7/4)^8/(3/2)^11 = 5764801/5668704 must be tempered out also. Taking this, multiplying it by the tetracot comma and taking the fourth root yields 245/243, which therefore must be tempered out also. The tetracot comma and 245/243 taken together define 7-limit octacot. | ||
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==The 88cET family== | ==The 88cET family== | ||
[[Gary_Morrison|Gary Morrison]] originally conceived of 88cET as composed of steps of exactly 88¢. Nonetheless, composers have recognized a kinship between strict 88cET and some other scales -- in particular, the 41st root of 8 (equivalent to taking three steps of [[ | [[Gary_Morrison|Gary Morrison]] originally conceived of 88-cent equal tuning (88cET) as composed of steps of exactly 88¢. Nonetheless, composers have recognized a kinship between strict 88cET and some other scales -- in particular, the 41st root of 8 (equivalent to taking three steps of [[41edo]] as a generator with no octaves), the 8th root of 3/2, and the 11th root of 7/4, the latter being a preferred variant of composer and software designer [[X._J._Scott|X. J. Scott]]. These three cousins of strict 88cET have single steps of approximately 87.805¢, 87.744¢, and 88.075¢, respectively. These small differences add up, as can be seen by examining the interval list below. | ||
==Intervals== | ==Intervals== | ||
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|- | |- | ||
! | Degree | ! | Degree | ||
! | 11th root | ! | 11th root <br>of 7/4 | ||
of 7/4 | |||
! | 88cET | ! | 88cET | ||
! | 41st root of 8 | ! | 41st root <br>of 8 | ||
! | [[8edf|8th root <br>of 3/2]] | |||
! | Solfege <br>syllable | |||
! | 8th root | ! | Some Nearby <br>JI Intervals | ||
of 3/2 | |||
! | Solfege | |||
! | Some Nearby | |||
|- | |- | ||
! colspan="6" | '''''first octave''''' | ! colspan="6" | '''''first octave''''' | ||
| Line 62: | Line 48: | ||
| | 175.489 | | | 175.489 | ||
| | reh | | | reh | ||
| | [[ | | | [[11/10]]=165.004, 21/19=173.268, [[10/9]]=182.404 | ||
|- | |- | ||
| | 3 | | | 3 | ||
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| | 263.233 | | | 263.233 | ||
| | ma | | | ma | ||
| | [[ | | | [[7/6]]=266.871 | ||
|- | |- | ||
| | 4 | | | 4 | ||
| Line 78: | Line 64: | ||
| | 350.978 | | | 350.978 | ||
| | mu | | | mu | ||
| | [[ | | | [[11/9]]=347.408, 27/22=354.547, 16/13=359.472 | ||
|- | |- | ||
| | 5 | | | 5 | ||
| Line 86: | Line 72: | ||
| | 438.722 | | | 438.722 | ||
| | mo | | | mo | ||
| | 32/25=427.373, [[ | | | 32/25=427.373, [[9/7]]=435.084, [[22/17]]=446.363 | ||
|- | |- | ||
| | 6 | | | 6 | ||
| Line 94: | Line 80: | ||
| | 526.466 | | | 526.466 | ||
| | fih | | | fih | ||
| | 19/14=528.687, 49/36=533.742, [[ | | | [[19/14]]=528.687, 49/36=533.742, [[15/11]]=536.95 | ||
|- | |- | ||
| | 7 | | | 7 | ||
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| | 614.211 | | | 614.211 | ||
| | se | | | se | ||
| | [[ | | | [[10/7]]=617.488 | ||
|- | |- | ||
| | 8 | | | 8 | ||
| Line 110: | Line 96: | ||
| | 701.955 | | | 701.955 | ||
| | sol | | | sol | ||
| | [[ | | | [[3/2]]=701.955 | ||
|- | |- | ||
| | 9 | | | 9 | ||
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| | 789.699 | | | 789.699 | ||
| | leh | | | leh | ||
| | [[ | | | [[11/7]]=782.492, 30/19=790.756, 128/81=792.180, [[19/12]]=795.558, 27/17=800.910, [[8/5]]=813.686 | ||
|- | |- | ||
| | 10 | | | 10 | ||
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| | 880 | | | 880 | ||
| | 878.049 | | | 878.049 | ||
| | | | | 877.444 | ||
| | la | | | la | ||
| | [[ | | | [[5/3]]=884.359 | ||
|- | |- | ||
| | 11 | | | 11 | ||
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| | 965.188 | | | 965.188 | ||
| | ta | | | ta | ||
| | [[ | | | [[7/4]]=968.826 | ||
|- | |- | ||
| | 12 | | | 12 | ||
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| | 1052.933 | | | 1052.933 | ||
| | tu | | | tu | ||
| | [[ | | | [[11/6]]=1049.363, 35/19=1057.627, 24/13=1061.427 | ||
|- | |- | ||
| | 13 | | | 13 | ||
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<span style=""><span style="">[http://micro.soonlabel.com/88cent_nonoctave/Prelude_in_88_Cent_Tuning.mp3 A Simple Prelude for 88 Cent Piano]</span></span> by [http://chrisvaisvil.com/?p=951 Chris Vaisvil] ([http://micro.soonlabel.com/88cent_nonoctave/A_Simple_Prelude_in_88_Cent_Tuning.pdf scordata]) | <span style=""><span style="">[http://micro.soonlabel.com/88cent_nonoctave/Prelude_in_88_Cent_Tuning.mp3 A Simple Prelude for 88 Cent Piano]</span></span> by [http://chrisvaisvil.com/?p=951 Chris Vaisvil] ([http://micro.soonlabel.com/88cent_nonoctave/A_Simple_Prelude_in_88_Cent_Tuning.pdf scordata]) | ||
[[Category: | [[Category:Equal-step tuning]] | ||
[[Category: | [[Category:Edonoi]] | ||