Major second: Difference between revisions

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A '''major second (M2)''' in the [[5L 2s|diatonic scale]] is an interval that spans one scale step with the major (wider) quality. It is generated by stacking 2 fifths [[Octave reduction|octave reduced]], and depending on the specific tuning, it ranges from 171 to 240 [[Cent|¢]] ([[7edo|1\7]] to [[5edo|1\5]]). It can be considered the large step of the diatonic scale.
A '''major second (M2)''' is an interval that spans one scale step in the [[5L 2s|diatonic]] scale with the major (wider) quality. It is generated by stacking 2 fifths [[octave reduction|octave reduced]], and depending on the specific tuning, it ranges from 171 to 240{{cent}} ([[7edo|1\7]] to [[5edo|1\5]]). It can be considered the large step of the diatonic scale.


In [[just intonation]], an interval may be classified as a major second if it is reasonably mapped to 1\7 and [[24edo|4\24]] (precisely one step of the diatonic scale and two steps of the chromatic scale). The use of 24edo's 4\24 as the mapping criteria here rather than [[12edo]]'s 2\12 better captures the characteristics of many intervals in the [[11-limit|11-]] and [[13-limit]].
In [[just intonation]], an interval may be classified as a major second if it is reasonably mapped to 1\7 and [[24edo|4\24]] (precisely one step of the diatonic scale and two steps of the chromatic scale). The use of 24edo's 4\24 as the mapping criteria here rather than [[12edo]]'s 2\12 better captures the characteristics of many intervals in the [[11-limit|11-]] and [[13-limit]].
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== In just intonation ==
== In just intonation ==
=== By prime limit ===
=== By prime limit ===
The '''Pythagorean ([[3-limit]]) major second''' is [[9/8]], which is 204 cents in size and corresponds to the MOS-based interval category of the diatonic major second. It is generated by [[stacking]] two just perfect fifths of [[3/2]]. There is also a '''Pythagorean diminished third''' of 65536/59049, which is about 180 cents in size. While called a "third", it is within the range of major seconds.
The Pythagorean ([[3-limit]]) major second is [[9/8]], which is 204 cents in size and corresponds to the mos-based interval category of the diatonic major second. It is generated by [[stacking]] two just perfect fifths of [[3/2]]. There is also a Pythagorean diminished third of [[65536/59049]], which is about 180 cents in size. While called a "third", it is within the range of major seconds.


Other major seconds exist in higher [[Prime limit|limits]], however, for example:
Other major seconds exist in higher [[prime limit|limits]], however, for example:


* The 5-limit '''ptolemaic major second''' is a ratio of [[10/9]], however in 5-limit harmony it is used alongside 9/8. It is about 182 cents.
* The 5-limit '''ptolemaic major second''' is a ratio of [[10/9]], however in 5-limit harmony it is used alongside 9/8. It is about 182 cents.
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=== By delta ===
=== By delta ===
See [[Delta-N ratio]]. Ratios that are marginal within the interval category and ambiguous with an adjoining one are marked with an asterisk.
See [[Delta-N ratio]]. Ratios that are marginal within the interval category and ambiguous with an adjoining one are marked with an asterisk.
{| class="wikitable"
{| class="wikitable"
! colspan="2" |Delta-1
! colspan="2" | Delta-1
! colspan="2" |Delta-2
! colspan="2" | Delta-2
! colspan="2" |Delta-3
! colspan="2" | Delta-3
|-
|-
|8/7
| 8/7
|231 ¢
| 231{{c}}
|15/13*
| 15/13*
|248 ¢
| 248{{c}}
|22/19*
| 22/19*
|253 ¢
| 253{{c}}
|-
|-
|9/8
| 9/8
|204 ¢
| 204{{c}}
|17/15
| 17/15
|217 ¢
| 217{{c}}
|23/20*
| 23/20*
|242 ¢
| 242{{c}}
|-
|-
|10/9
| 10/9
|182 ¢
| 182{{c}}
|19/17
| 19/17
|193 ¢
| 193{{c}}
|25/22
| 25/22
|221 ¢
| 221{{c}}
|-
|-
|11/10*
| 11/10*
|165 ¢
| 165{{c}}
|21/19
| 21/19
|173 ¢
| 173{{c}}
|26/23
| 26/23
|212 ¢
| 212{{c}}
|-
|-
|
|  
|
|  
|
|  
|
|  
|28/25
| 28/25
|196 ¢
| 196{{c}}
|-
|-
|
|  
|
|  
|
|  
|
|  
|29/26
| 29/26
|189 ¢
| 189{{c}}
|-
|-
|
|  
|
|  
|
|  
|
|  
|31/28
| 31/28
|176 ¢
| 176{{c}}
|-
|-
|
|  
|
|  
|
|  
|
|  
|32/29*
| 32/29*
|170 ¢
| 170{{c}}
|}
|}


== In EDOs ==
== In edos ==
The following table lists the best tuning of 10/9, 9/8, and 8/7, as well as other major seconds if present, in various significant [[EDO|EDOs]].
The following table lists the best tuning of 10/9, 9/8, and 8/7, as well as other major seconds if present, in various significant [[edo]]s.
{| class="wikitable"
{| class="wikitable"
!EDO
! Edo
!10/9
! 10/9
!9/8
! 9/8
!8/7
! 8/7
!Other major seconds
! Other major seconds
|-
|-
|5
| 5
| colspan="3" |240c
| colspan="3" | 240{{c}}
|
|  
|-
|-
|7
| 7
| colspan="3" |171c
| colspan="3" | 171{{c}}
|
|  
|-
|-
|12
| 12
| colspan="3" |200c
| colspan="3" | 200{{c}}
|
|  
|-
|-
|15
| 15
|160c
| 160{{c}}
| colspan="2" |240c
| colspan="2" |240{{c}}
|
|  
|-
|-
|16
| 16
|*
| *
| colspan="2" |225c
| colspan="2" | 225{{c}}
|
|  
|-
|-
|17
| 17
| colspan="3" |212c
| colspan="3" | 212{{c}}
|
|  
|-
|-
|19
| 19
| colspan="2" |189c
| colspan="2" | 189{{c}}
|253c
| 253{{c}}
|
|
|-
|-
|22
| 22
|164c
| 164{{c}}
| colspan="2" |218c
| colspan="2" | 218{{c}}
|
|  
|-
|-
|24
| 24
| colspan="2" |200c
| colspan="2" | 200{{c}}
|250c
| 250{{c}}
|
|
|-
|-
|25
| 25
| colspan="2" |192c
| colspan="2" | 192{{c}}
|240c
| 240{{c}}
|
|
|-
|-
|26
| 26
| colspan="2" |185c
| colspan="2" | 185{{c}}
|231c
| 231c
|
|
|-
|-
|27
| 27
|178c
| 178{{c}}
| colspan="2" |222c
| colspan="2" | 222{{c}}
|
|  
|-
|-
|29
| 29
|166c
| 166{{c}}
|207c
| 207{{c}}
|248c
| 248{{c}}
|
|  
|-
|-
|31
| 31
| colspan="2" |194c
| colspan="2" | 194{{c}}
|232c
| 232{{c}}
|
|  
|-
|-
|34
| 34
|176c
| 176{{c}}
|212c
| 212{{c}}
|247c
| 247{{c}}
|
|  
|-
|-
|41
| 41
|176c
| 176{{c}}
|205c
| 205{{c}}
|234c
| 234{{c}}
|
|  
|-
|-
|53
| 53
|181c
| 181{{c}}
|204c
| 204{{c}}
|226c
| 226{{c}}
|249c ≈ 15/13
| 249{{c}} ≈ 15/13
|}
|}


== In moment-of-symmetry scales ==
== In mos scales ==
Being a small interval, major seconds generate a number of monosmall and monolarge MOSes.
Being a small interval, major seconds generate a number of monosmall and monolarge [[mos]].


These tables start from the last monolarge [[MOS]] generated by the interval range.
These tables start from the last monolarge mos generated by the interval range.


MOSes with more than 12 notes are not included.
Scales with more than 12 notes are not included.


{| class="wikitable"
{| class="wikitable"
|-
|-
! Range
! Range
! colspan="3" | MOS
! colspan="3" | Mos
|-
|-
| 150–171{{c}}
| 150–171{{c}}