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Hello folks,
Would you please help with some of these questions?
The exercise book I am working from, Keyboard Theory Level 2 by Grace Vandendool doesn't always have the answers to my insane questions.

1. What are the rules for writing cadences in chorale style?

2. Tetrachords:
i.e. C D E F G A B C ascending
lower upper

therefore C B A G F E D C descending
upper lower

Is my assumption correct?

3. What us the formula for minor pentatonic scale?

4. Whole tone scale: is there a major and a minor form?

Thank you for your responses.

Emrys

I don't know the answers to your questions, but perhaps you can find them at http://www.musictheory.net

Hello Emrys,
Here are some answers for you.
1. Use voice leading in the parts. Voice leading is the idea of making a part logical and moving to the nearest chord tone within the singer's range in each part. Don't use leaps and try not to double the root, especially if 7th chords are involved.
2. The minor pentatonic scale in its simplest form is the I II III V VI of the relative major associated with the minor scale or chord you are working with. For example, if you are working with an A minor chord, C major is the relative major, so the notes in the A minor pentatonic would be C D E G A (the I II III V VI of C).
Of course if you were wanting to give the listener the sound of the A minor pentatonic scale, you would not start the scale on C, but on A, so the answer is A C D E G.
3. The whole tone scale cannot be considered minor because of the fact that the third tone of it is always a major third above the root, so it always give a majorish sound.
Best of luck!

The Essentials of Part-Writing

Normal Doubling: Diatonic major and minor triads
a) root in bass: double root
b) first inversion: double the soprano note
c) second inversion: double the bass note
d) exception, minor triads, root or third in bass: the third of a minor triad is often doubled,
particularly when this third is the tonic, subdominant or dominant note of the key.

Diminished triad (usually found in first inversion only): double the third; when the fifth is in the soprano, the fifth is usually doubled.
Augmented triad: double the bass note
Seventh chord: normally, all four voices are present. In the major-minor seventh chord, the root is often doubled and the fifth omitted.
Altered triad: normally, same doubling as non-altered triads; avoid doubling the altered note.

General Rules:
a) Move each voice the shortest distance possible.
b) Move the soprano and bass in contrary or oblique motion if possible.
c) Avoid doubling the leading tone, any altered note, any non-harmonic tone, or the seventh of a seventh chord.
d) Avoid parallel fifths, parallel octaves and the melodic interval of the augmented second.

Chord Connection: Triad Roots
When the bass tones of two successive triads are the roots of the triads

Triad Roots are repeated.
Rule 1. Both triads may be written in the same position, or each may be in different position.
Triad position should be changed:
a) when necessary to keep voices in correct pitch range.
b) when necessary to keep correct voice distribution (two roots, one third, one fifth).
c) to avoid large leaps in an inner part

Triad roots are a fifth apart.
Rule 2A. Retain the common tone; move the other voices stepwise.
Rule 2B. Move the three upper voices in similar motion to the nearest tones of the next triad.
Rule 2C. Move the third of the first triad up or down the interval of a fourth to the third of the second triad,
hold the common tone and move the other voice by step.
Rule 2D. (Exception) At the cadence, the root of the final tonic triad may be tripled, omitting the fifth.

Triad roots are a second apart.
Rule 3. The three upper voices move contrary to the bass.


Triad roots a third apart.
Rule 4A. Hold the two common tones; the upper voice moves stepwise.
Rule 4B. When the soprano moves by leap, the second triad may be in either close or open position.

Rule 5. When it is impossible or undesirable to follow normal rules for triads with roots in bass, double the third in the second of the two triads. But if this third is the leading tone or any altered tone, double the third in the first of the two triads.

Triads in Inversion
Progression to or from a triad in inversion, a triad with a doubled third, or a triad with any unusual doubling
Rule 6A. Write the two voices moving to or from the doubled note first, using oblique or contrary motion if possible.
Rule 6B. When first inversions of triads are found in succession, each triad must have a different doubling to avoid parallel octaves, or the same doubling may appear in different pairs of voices. Avoid doubling the leading tone or any altered tone. Approach and leave each doubled tone using Rule 6A.

Position Change
Rule 7. Triad position may be changed.
a) at a repeated triad.
b) using Rule 2C.
c) at a triad in inversion or a triad with unusual doubling, following Rule 6A.

Non-Harmonic Tones
Rule 8. A non-harmonic tone temporarily replaces a harmonic tone.
Write the triad with normal doubling if possible and substitute the non-harmonic tone for one of the chord tones. approach and leave the non-harmonic tone according to the definition of the non-harmonic tone being used.


Seventh Chords
Rule 9. The seventh of a seventh chord, its note of approach and its note of resolution comprise a three-note figure similar to certain non-harmonic tone figures: passing tone, suspension, appoggiatura, and upper neighbor. %0

Pentatonic Minor Scale: 1 b3 4 5 b7
example: C Eb F G Bb (fingered 13 123)
The C Minor Penataonic Scale can work well for most of the chords found in the keys of Eb major, Ab Major, and Bb Major

Pentatonic Major: 1 2 3 5 6
example: C D E G A (fingered 123 12)
The C Major Penataonic Scale can works well for most of the chords found in the keys of C major, F Major.

There are only two Whole Tone Scales possible
C D E F# G# A# etc
Fingering (12 1234)

The other Whole Tone Scale is:
B C# D# F G A etc
Fingering (123 123)