teddy, you don't need to be worrying out-loud whether I am getting heated, because I'm not; but look at these queries, and what I'm being asked to explain. It might appear to you as "heat," but it's not. What do you take me for, a belligerent, alcoholic boor on a "dry drunk" rant? Oh, well...I'll just chalk it up to "the curse of intelligence." Now that we've gotten
that cleared up...
You don’t have to bother at all! I am asking out of interest, the jazz that I know is in 4/4 time and of course 5/4 and 7/4 for Brubeck I have heard the odd piece in ¾ time but can’t recall the title, I can’t see the relationship to your [ African-originated rhythmic elements, dividing the beat into 3, using compound time signatures] this is your first criteria..... so can you give an example, I may be misunderstanding your meaning.
Ok, ok....I chased down an old blog of mine...I'm doing you a favor, I hope you appreciate that.
Jazz is based on an African, non-Western division of the main pulse beat. This is called a "shuffle" in Blues, and is used in jazz. Our Western notation system cannot properly convey this, and instead arrangers will notate in 4/4 and specify "shuffle feel." This jazz rhythm is not a "feel," it is a division of the main pulse into three rather than two.
To explain further, the main pulse of a blues or jazz song divides the measure into 4 parts, exemplified by the "walking" bass, which plays in 1-2-3-4 (That's why you think it's in 4/4).
However, there are accents which are divisions of 3 which cannot be notated properly in 4/4, because our time signature system does not allow for "3" values to be placed in the bottom number of the time signature. Everything goes in multiples of two: Whole, half, quarter, eighth, sixteenth, and so on.
To get a "three" value, we must place a "dot" after the note. You can't put a "dotted" note in the bottom of a time signature.
Notating 3 divisions as "triplets" is too cluttering. The only
truly accurate way to notate this shuffle is to use a "compound" time signature, 12/8. This is counter-intuitive, because the main bass-pulse (with the bass drum) is on 1-4-7-10. It's counter-intuitive to count to 12 in this manner, because the main pulse is still felt as 1-2-3-4. So most arrangers simply write
"shuffle feel" next to the 4/4 time signature.
"Compound" rhythms allow the beat to be subdivided into 2 or 3 parts (factors of 12). African drummers "played" with this ambiguity, creating complex interplay, which Steve Reich studied closely.
New cross-cultural elements took this even further, to assimilate jazz rhythms into their existing cultural norms. Bossa Nova, for example, transformed the African-derived 3-division of black jazz into an evenly-divided 4/4, common in South America.
I don’t understand that at all. Pentatonic scales come from all over the world so what is special in African Pentatonic Scales? Again I am curious, that’s all.
Uh-huh, right. Just curious. The pentatonic scale is where the "blues" scale is derived. You should not ever, ever question the use of pentatonic scales in jazz. You should understand this implicitly, immediately. Breathe it like air.
For the answer to "What makes Africal pentatonics different?": they are non-Western, and use "just" intervals, like most folk musics. Go to WIK and read a little, if you need more info; this is where my "long-winded explanations" stop.
The "harmonic seventh" or 7/4 interval (about 968.826 cents), is also known as the septimal minor seventh. It has been a contentious issue throughout the history of music theory; it is 31 cents flatter than an equal-tempered minor seventh. Some assert the 7/4 is one of the blue notes used in jazz."
http://en.wikipedia.org/wiki/Harmonic_seventh
Interestingly, when this flatter seventh is used, the dominant seventh chord's "need to resolve" down a fifth is weak or non-existent. This chord is often used on the tonic (written as I7) and functions as a "fully resolved" final chord.
A-ha! So maybe THAT'S why blues uses all seventh chords (I7-IV7-V7)...it's also used in "barbershop quartet" singing.
That "blue" third, and the flatter "harmonic seventh" have their origins in African music. I'm no expert, but I do know that the pentatonic scale was used extensively, as it is in almost all "folk" musics.
I suggest that 99% of solos in the big bands were improvised to a large degree... you call it flexibility so where does that get us, are they jazz bands ?
Well, this would appear to contradict your earlier post:
Earlier in the thread I brought up the subject of the larger bands Ellington, Goodman, Herman, Kenton etc which were called Jazz bands but in truth because of their size and the complexity of the music had to use scores so I contend these were not jazz bands, what is your take on that?
Yes, I consider the Fletcher Henderson Orchestra to be jazz. If you disagree, that's your privilege.