Just Hammond: Difference between revisions

table 2 beautified
table 3 (E-A-B) supplemented
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This numbering scheme is consistent with the scheme used by [[Bill Sethares]]<ref>Sethares, William A. ''Tuning Timbre Spectrum Scale.'' London: Springer Verlag , 1999.</ref> : “''In general, the n<sup>th</sup> octave contains 2<sup>n-1</sup> pitches''.”  
This numbering scheme is consistent with the scheme used by [[Bill Sethares]]<ref>Sethares, William A. ''Tuning Timbre Spectrum Scale.'' London: Springer Verlag , 1999.</ref> : “''In general, the n<sup>th</sup> octave contains 2<sup>n-1</sup> pitches''.”  


== Mapping the Hammond’s Rational Intervals (cont.): Examples ==
== Mapping Hammond’s Rational Intervals (cont.): Examples ==
The following examples illustrate how to map intervals or chords to the harmonic series. In the first example we map the combination of a Hammond Organ’s note E and a higher note A (a fourth up):
The following examples illustrate how to map intervals or chords to the harmonic series. In the first example we map the combination of a Hammond Organ’s note E and a higher note A (a fourth up):


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| style="text-align: center;" | 9.6
| style="text-align: center;" | 9.6
|-
|-
| colspan="3" style="font-weight:bold;" |  
| colspan="3" |  
Multiply     -----><br>
Multiply --------><br>
to find (D)'s least<br>  
to find (D)'s least<br>  
common multiple<br>  
common multiple<br>  
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The resulting interval E-A appears between partial # 206 and partial # 275.<br>  
The resulting interval E-A appears between partial # 206 and partial # 275.<br>  
The frequency ratio is (275:206), which equals 500.14 cents.
The frequency ratio is (275:206), which equals 500.14 cents.
Amending an upper note B, the next example illustrates how to map the resulting sus4-chord to the harmonic series.
{| class="wikitable"
! rowspan="3" style="text-align: center;" |<br><br><br>
Pitch<br>
Class
! colspan="2" style="text-align: center;" |
HAMMOND<br>
Gear Ratio<br>
(canceled)
! colspan="6" style="text-align: center;" |
Prime<br>
Factorization...
! style="text-align: center;" |
Ascending<br>
Partial Numbers of<br>
an Overtone Scale
! style="text-align: center;" |
Partial found<br>
in Octave
|-
| style="text-align: center;" | (C)
| style="text-align: center;" | (D)
| rowspan="2" colspan="6" style="text-align: center; background-color:#cbcefb;" |
...of Column (D)<br><br><br><br>
| rowspan="2" style="text-align: center;" |
Recalculated<br>
Numerator =<br>
Partial#<br>
P=LCM *(C)/(D)
| rowspan="2" style="text-align: center;" |
Counted<br>
from 1/1:<br>
Octave# =<br>
1+(ln(P)/ln(2))
|-
| colspan="2" style="text-align: center;" | Fraction
(C)/(D)
|-
| style="text-align: center;" | E
| style="text-align: right; background-color:#ffffff;" | 103
| style="font-weight:bold; background-color:#ffffff;" | 100
| style="background-color:#cbcefb;" | 2
| style="background-color:#cbcefb;" | 2
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" | 5
| style="background-color:#cbcefb;" | 5
| style="background-color:#cbcefb;" |
| style="text-align: center;" | 1442
| style="text-align: center;" | 11.5
|-
| style="text-align: center;" | A
| style="text-align: right; background-color:#ffffff;" | 11
| style="font-weight:bold; background-color:#ffffff;" | 8
| style="background-color:#cbcefb;" | 2
| style="background-color:#cbcefb;" | 2
| style="background-color:#cbcefb;" | 2
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" |
| style="text-align: center;" | 1925
| style="text-align: center;" | 11.9
|-
| style="text-align: center;" | B
| style="text-align: right;" | 54
| style="font-weight:bold;" | 35
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" | 5
| style="background-color:#cbcefb;" |
| style="background-color:#cbcefb;" | 7
| style="text-align: center;" | 2160
| style="text-align: center;" | 12.1
|-
| colspan="3" |
Multiply --------><br>
to find (D)'s least<br>
common multiple<br>
(LCM)
| style="font-weight:bold; background-color:#cbcefb;" | 2<br><br><br><br>
| style="font-weight:bold; background-color:#cbcefb;" | 2<br><br><br><br>
| style="font-weight:bold; background-color:#cbcefb;" | 2<br><br><br><br>
| style="font-weight:bold; background-color:#cbcefb;" | 5<br><br><br><br>
| style="font-weight:bold; background-color:#cbcefb;" | 5<br><br><br><br>
| style="font-weight:bold; background-color:#cbcefb;" | 7<br><br><br><br>
| style="text-align: center; font-weight:bold;" |
1400<br><br>
(LCM)<br><br>
| style="text-align: center;" |
11.4<br><br>
Decimal printed<br>
for orientation only
|}