Tritone chord root movement

[alez]

The other day I was talking with a friend who is a composer and teaches counterpoint about these first few measures of a Bach prelude:



She noted that it's unusual (and "harsh") for both lines to have simultaneous tritone intervals (as they land on measure #9). It indeed sounds to me very striking and unexpected (like the crude modulation it probably is?).

This got me thinking how tritone chord root movement is not entirely unusual in jazz. I can think of two fairly common chord sequences that have it:

1) C F Bb7 Em7 A7 Dm7 G7 (that's when a backdoor, instead of resolving "home" to end the tune, goes to a turnaround, perhaps at the end of a chorus to start the following one).

2) C F Bm7b5 E7 Am (Autumn Leaves and Manhã de carnaval / Black Orpheus / A Day in the Life of a Fool use this, also Fly Me to the Moon, but shifted, positioned differently).

I'm sure others like C F#m7b5 B7 C may have been used although I don't remember having seen any.

#2 caught my attention long ago because I thought the F is not really required at all but sort of added to ease moving on to the Bm7b5, if that's so, I wondered why choose a chord with a root a tritone away from its target.

Out of sheer curiosity I was wondering if you may like to comment on any of this.

Also I'm curious to know if, in such cases in jazz, typically the bass will actually sound the tritone or play any of the chords in inversion to avoid the interval.

[Tal_175]

1) C F Bb7 Em7 A7 Dm7 G7 (that's when a backdoor, instead of resolving "home" to end the tune, goes to a turnaround, perhaps at the end of a chorus to start the following one).

Note the actual home for Bb7 is A7. Backdoor actually wants to resolve to the VI but typically resolves to I by proximity (especially I6) since they share the same function and some of the chord tones.
What's going on (to my ears) in Bb7 Em7 A7 is a delayed resolution to A7. A ii chord is added in front of the targeted dominant. This is very common all over the place. This type of backdoor movement also happens in rhythm changes, Days of Wine and Roses etc.

2) C F Bm7b5 E7 Am (Autumn Leaves and Manhã de carnaval / Black Orpheus / A Day in the Life of a Fool use this).

This is just cycle of fours in the key. If you start from I and go in 4ths you'll visit all the chords until you get back to one. I IV VII III VI II V I. It's really the engine of jazz harmony.

[Christian Miller]

Ah yes I see what you mean. I’d have to hear it!

Simple answer - I don’t really know.

Sent from my iPhone using Tapatalk

[Christian Miller]

The other day I was talking with a friend who is a composer and teaches counterpoint about these first few measures of a Bach prelude:



She noted that it's unusual (and "harsh") for both lines to have simultaneous tritone intervals (as they land on measure #9). It indeed sounds to me very striking and unexpected (like the crude modulation it probably is?).

This got me thinking how tritone chord root movement is not entirely unusual in jazz. I can think of two fairly common chord sequences that have it:

1) C F Bb7 Em7 A7 Dm7 G7 (that's when a backdoor, instead of resolving "home" to end the tune, goes to a turnaround, perhaps at the end of a chorus to start the following one).

2) C F Bm7b5 E7 Am (Autumn Leaves and Manhã de carnaval / Black Orpheus / A Day in the Life of a Fool use this).

I'm sure others like C F#m7b5 B7 C may have been used although I don't remember having seen any.

#2 caught my attention long ago because I thought the F is not really required at all but sort of added to ease moving on to the Bm7b5, if that's so, I wondered why choose a chord with a root a tritone away from its target.

Out of sheer curiosity I was wondering if you may like to comment on any of this.

Also I'm curious to know if, in such cases in jazz, typically the bass will actually sound the tritone or play any of the chords in inversion to avoid the interval.

Re #1 - I would tend to view Em7 there as an inverted C chord. Or a functional tonic sub if you like.

Re:#2 It’s customary in ‘common practice music’ to chromatically alter a cycle 4 profession to fit the prevailing modality. You end up usually with an augmented fourth moving from degree VI to VII etc. Many examples from Bach etc.


Sent from my iPhone using Tapatalk

[alez]

Note the actual home for Bb7 is A7. Backdoor actually wants to resolve to the VI but typically resolves to I by proximity (especially I6) since they share the same function and some of the chord tones.
What's going on (to my ears) in Bb7 Em7 A7 is a delayed resolution to A7. A ii chord is added in front of the targeted dominant. This is very common all over the place. This type of backdoor movement also happens in rhythm changes, Days of Wine and Roses etc.

Wow, I never thought of that in those terms, much more in these:

Re #1 - I would tend to view Em7 there as an inverted C chord. Or a functional tonic sub if you like.

It's great to have both views.

Ah yes I see what you mean. I’d have to hear it!

I'll try to find a recording. You don't want to hear my sorry attempts at it.

Simple answer - I don’t really know.

[Tal_175]

Wow, I never thought of that in those terms, much more in these:

Well, let your ears decide. Play Bb7 to Emin7. Do you actually hear a satisfying resolution? Now play Bb7 to A7 a couple of times, then Bb7 Emin7 A7. Do you hear a delayed resolution? In my case, I can hear the delayed resolution fairly clearly but maybe you hear differently.

[Christian Miller]

Actually thinking about it I’m sort of going more with Tal’s way of looking at it. Think ‘Bernie’s Tune’.


Sent from my iPhone using Tapatalk

[alez]

Ah yes I see what you mean. I’d have to hear it!

This link should play it:
https://mega.nz/file/LEJQxSZL#h-zSy5...rBp6sdC2cSMv1g

I've done that with a sequencer, so it doesn't sound great. I've included what's on the screen capture above plus one A minor measure that follows.

[alez]

Well, let your ears decide. Play Bb7 to Emin7. Do you actually hear a satisfying resolution? Now play Bb7 to A7 a couple of times, then Bb7 Emin7 A7. Do you hear a delayed resolution? In my case, I can hear the delayed resolution fairly clearly but maybe you hear differently.

To me it sounds like a 2-step cadence (F Bb7) that doesn't resolve (to C, because that's the one resolution my ear is used to) but instead goes to a turnaround. In that sense, similar to the typical Dm7 G7 Em7 A7 Dm7 G7 C "detour".

[alez]

Any other chord root tritone motion common enough to mention?

[pamosmusic]

Diatonic IV to vii a la Autumn leaves.

[pauln]

Sounds like

1 Dm
2 Dm
3 Gm/D
4 Gm/D
5 C#dim/D
6 C#dim/D | Dm
7 Dm
8 Dm
9 A Harmonic Minor /G#
10 A Major/ E Dorian

Measure 9 does not sound harsh to me.

[mr. beaumont]

Doesn't sound harsh to me at all.

[alez]

Actually thinking about it I’m sort of going more with Tal’s way of looking at it. Think ‘Bernie’s Tune’.

I don't see Bernie's Tune like that. I look at it the same way I look at a minor blues turnaround: F7 E7 Am. In Bernie's, E7 comes as Bm7b5 E7. So to me it's more like Autumn Leaves, but with F7 instead of F.

Diatonic IV to vii a la Autumn leaves.

Yes, that's the second case I described on the first post.

Measure 9 does not sound harsh to me.

Doesn't sound harsh to me at all.

It sounded more striking to me when I was playing it

[alez]

Sounds like

1 Dm
2 Dm
3 Gm/D
4 Gm/D
5 C#dim/D
6 C#dim/D | Dm
7 Dm
8 Dm
9 A Harmonic Minor /G#
10 A Major/ E Dorian

I'm not sure about measure #10:
C# is not present, so no A "major" as such major.
There's G# and there's no G, so no "dorian" as such minor.

I'd go with E7 (and that's why I included the Am that follows) but that's probably wrong because the first note is A. I'm going to say A major too (but no E dorian). Is it correct that this music was written before chords started being looked at the way we are now used to?

[nevershouldhavesoldit]

I’ve been trying to understand how you all got to the content in this thread from a simple observation on Baroque counterpoint.

Yes, there are simultaneous tritone jumps from the F to the B and from the D to the G#. But these occur in parallel melodic lines and seem to me to have no relation at all to tritone chord root movement. The closest I can pull this to an analogue in jazz may be that the G# B diad to which the lines in bar 8 “resolve” could have been Freddie Green’s first stroke in bar 9 (as the character notes in an implied D dim), if Basie did the Bach piece as an 8 bar blues (Dm Gm A7 Dm) with an extended turnaround.

I see nothing suggesting chord root movement to me in the OP’s illustration. I think this may be an example of theory for theory’s sake. It arose from a simple observation on contrapuntal music, which is where it should stay IMO. Making simple things complicated is at the heart of so many blazing solos that say nothing more than “I know my theory”.

[pamosmusic]

I’ve been trying to understand how you all got to the content in this thread from a simple observation on Baroque counterpoint.

Yes, there are simultaneous tritone jumps from the F to the B and from the D to the G#. But these occur in parallel melodic lines and seem to me to have no relation at all to tritone chord root movement. The closest I can pull this to an analogue in jazz may be that the G# B diad to which the lines in bar 8 “resolve” could have been Freddie Green’s first stroke in bar 9 (as the character notes in an implied D dim), if Basie did the Bach piece as an 8 bar blues (Dm Gm A7 Dm) with an extended turnaround.

I see nothing suggesting chord root movement to me in the OP’s illustration. I think this may be an example of theory for theory’s sake. It arose from a simple observation on contrapuntal music, which is where it should stay IMO. Making simple things complicated is at the heart of so many blazing solos that say nothing more than “I know my theory”.

I don’t think the OP was attempting to analyze the Bach in these terms. Just noticing that it was considered unusual in the context of counterpoint, but that it is not terribly unusual in jazz harmony

[Christian Miller]

Not that anyone asked but at a glance it’s a short Quiescenza in Dm (Dm Gm/D C#o7/D - classic Bach prelude move see also bwv999) followed by a move into the dominant of Am (E7) via a 6 4 chord (Dm/A G#o7 E.)

For extra Nerd points note the ascending form melodic minor used in decent in bar 10. Classic German late baroque.

The B natural could have been prepared before its appearance in bar 9 by adding it into the previous bar to make Dm a clear subdominant chord of A minor. Bach doesn’t do this which is interesting.

Thematic statement followed by modulation to the dominant key. If I had to guess, you’d next have the same gesture as the first 6 bars transposed to Am? Don’t know the piece.

Sent from my iPhone using Tapatalk

[ragman1]

First page.

[ragman1]

simultaneous tritone intervals (as they land on measure #9).

I'm not good at this stuff and maybe I'm stupid, but I don't see any tritone intervals in #9.

The two notes sounding together in #9 are B natural and bass G#. Not a tritone.

Admittedly, the bass G# is a quarter note so it may be sounding while the F goes by but it's scarcely a danger to shipping.

[Tal_175]

I'm not good at this stuff and maybe I'm stupid, but I don't see any tritone intervals in #9.

The two notes sounding together in #9 are B natural and bass G#. Not a tritone.

Admittedly, the bass G# is a quarter note so it may be sounding while the F goes by but it's scarcely a danger to shipping.

Both the treble clef and bass clef have a leap of tritone when going to the first beat of measure 9. F goes up to B in the treble clef and D goes down to G# in the bass clef.

[ragman1]

So the first tritone is F-B in the treble. The second is D-G#(Ab) in the bass. and both span #8 and #9. Got it, thanks.

But it all sounds perfectly good so I suppose it's just a theoretical niggle :-)

[ragman1]

Re. the chord root tritone moves, take:

CM7 - FM7 - Bm7b5/E7b9 - Am7

It sounds pretty good so I'm wondering what the issue is. Why is the fact of the tritone alarming or contentious? Or is this some kind of medieval superstition buried deep in the consciousness popping up unexpectedly?

[ragman1]

Now if the next chords were:

CM7 - FM7 - Bm7b5/E7b9 - Am7
Eb7 - Am7b5/D7b9 - Gm7 - Db7b5

that would make a nice loop. Drive the devout out of their minds :-)

[Christian Miller]

Tritones were always fine, apparently that's a popular myth... There's quite a good Adam Neely video on it. Actually one of his best IMO.