Extended Chord Tension Counter (9/11/13)
Count explicitly declared 9/11/13 tensions preserving chromatic variants and collapsing exact duplicates; degree spelling is required because pitch classes alone cannot distinguish extensions from lower chord members.
Description
Extensions need declared compound degrees.
Extensions need declared compound degrees. Pitch classes alone cannot distinguish a ninth from a second or an eleventh from a fourth.1
Enter aligned nonempty degrees from 1,3,5,7,9,11,13 and integer alterations−2…2. Preserve first occurrence of each exact tension spelling; return count/list and presence flags for 9/11/13.
When to use Extended Chord Tension Counter (9/11/13)
Use Extended Chord Tension Counter (9/11/13) when you need to evaluate the supplied records under the calculation and evidence rules below. Different alterations of one degree count separately; lower degrees are not tensions. No chord compatibility or voicing is inferred.
Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.
How to use Extended Chord Tension Counter (9/11/13) and understand its results
- Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.
- Enter declaredExtensionDegrees, declaredChromaticAlterations using the field table and calculation rules, then run the tool.
- Read uniqueTensionCount, ninthTensionPresent, eleventhTensionPresent, thirteenthTensionPresent, tensionSpellings. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| declaredExtensionDegrees | Declared extension degrees | list of number | Required |
| declaredChromaticAlterations | Declared chromatic alterations | list of number | Required |
Enter aligned nonempty degrees from 1,3,5,7,9,11,13 and integer alterations−2…2. Preserve first occurrence of each exact tension spelling; return count/list and presence flags for 9/11/13.
tensions=unique spelled altered degrees≥9 Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| uniqueTensionCount | Unique tension count | number |
| ninthTensionPresent | Ninth tension present | boolean |
| eleventhTensionPresent | Eleventh tension present | boolean |
| thirteenthTensionPresent | Thirteenth tension present | boolean |
| tensionSpellings | Tension spellings | list of string |
{
"input": {
"declaredExtensionDegrees": [
7,
9,
11,
13,
9
],
"declaredChromaticAlterations": [
0,
0,
1,
-1,
0
]
},
"output": {
"uniqueTensionCount": 3,
"ninthTensionPresent": true,
"eleventhTensionPresent": true,
"thirteenthTensionPresent": true,
"tensionSpellings": [
"9",
"#11",
"b13"
]
}
}Limitations and assumptions
Different alterations of one degree count separately; lower degrees are not tensions. No chord compatibility or voicing is inferred.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Seventh Chord Type Classifier: Seventh quality depends on the complete root-relative pitch-class set. Doublings do not create additional chord members. For a complementary task, use Chord Inversion From Bass Note: Inversion identifies which spelled chord member is the supplied actual bass. A nonchord bass should remain visible rather than forced into an inversion.
References
-
Extended Chord Tension Counter (9/11/13) — tool.io
Similar or alternative tools
- Seventh Chord Type Classifier
Seventh quality depends on the complete root-relative pitch-class set. Doublings do not create additional chord members.
- Chord Inversion From Bass Note
Inversion identifies which spelled chord member is the supplied actual bass. A nonchord bass should remain visible rather than forced into an inversion.