Major second: Difference between revisions
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A '''major second (M2)''' in the [[5L 2s|diatonic | 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 | 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 [[ | 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{{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 | == 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 [[ | 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 | ||
!10/9 | ! 10/9 | ||
!9/8 | ! 9/8 | ||
!8/7 | ! 8/7 | ||
!Other major seconds | ! Other major seconds | ||
|- | |- | ||
|5 | | 5 | ||
| colspan="3" | | | colspan="3" | 240{{c}} | ||
| | | | ||
|- | |- | ||
|7 | | 7 | ||
| colspan="3" | | | colspan="3" | 171{{c}} | ||
| | | | ||
|- | |- | ||
|12 | | 12 | ||
| colspan="3" | | | colspan="3" | 200{{c}} | ||
| | | | ||
|- | |- | ||
|15 | | 15 | ||
| | | 160{{c}} | ||
| colspan="2" | | | colspan="2" |240{{c}} | ||
| | | | ||
|- | |- | ||
|16 | | 16 | ||
|* | | * | ||
| colspan="2" | | | colspan="2" | 225{{c}} | ||
| | | | ||
|- | |- | ||
|17 | | 17 | ||
| colspan="3" | | | colspan="3" | 212{{c}} | ||
| | | | ||
|- | |- | ||
|19 | | 19 | ||
| colspan="2" | | | colspan="2" | 189{{c}} | ||
| | | 253{{c}} | ||
| | | | ||
|- | |- | ||
|22 | | 22 | ||
| | | 164{{c}} | ||
| colspan="2" | | | colspan="2" | 218{{c}} | ||
| | | | ||
|- | |- | ||
|24 | | 24 | ||
| colspan="2" | | | colspan="2" | 200{{c}} | ||
| | | 250{{c}} | ||
| | | | ||
|- | |- | ||
|25 | | 25 | ||
| colspan="2" | | | colspan="2" | 192{{c}} | ||
| | | 240{{c}} | ||
| | | | ||
|- | |- | ||
|26 | | 26 | ||
| colspan="2" | | | colspan="2" | 185{{c}} | ||
|231c | | 231c | ||
| | | | ||
|- | |- | ||
|27 | | 27 | ||
| | | 178{{c}} | ||
| colspan="2" | | | colspan="2" | 222{{c}} | ||
| | | | ||
|- | |- | ||
|29 | | 29 | ||
| | | 166{{c}} | ||
| | | 207{{c}} | ||
| | | 248{{c}} | ||
| | | | ||
|- | |- | ||
|31 | | 31 | ||
| colspan="2" | | | colspan="2" | 194{{c}} | ||
| | | 232{{c}} | ||
| | | | ||
|- | |- | ||
|34 | | 34 | ||
| | | 176{{c}} | ||
| | | 212{{c}} | ||
| | | 247{{c}} | ||
| | | | ||
|- | |- | ||
|41 | | 41 | ||
| | | 176{{c}} | ||
| | | 205{{c}} | ||
| | | 234{{c}} | ||
| | | | ||
|- | |- | ||
|53 | | 53 | ||
| | | 181{{c}} | ||
| | | 204{{c}} | ||
| | | 226{{c}} | ||
| | | 249{{c}} ≈ 15/13 | ||
|} | |} | ||
== In | == In mos scales == | ||
Being a small interval, major seconds generate a number of monosmall and monolarge | Being a small interval, major seconds generate a number of monosmall and monolarge [[mos]]. | ||
These tables start from the last monolarge | These tables start from the last monolarge mos generated by the interval range. | ||
Scales with more than 12 notes are not included. | |||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
! Range | ! Range | ||
! colspan="3" | | ! colspan="3" | Mos | ||
|- | |- | ||
| 150–171{{c}} | | 150–171{{c}} | ||