# Topic: ORCH: Modulation by whole tone via dim 7th and Gr6

1. ## ORCH: Modulation by whole tone via dim 7th and Gr6

Okay, here\'s a little theoretically sequence I\'ve been developing:

Let\'s start out in the key of C, just to make things easy. (Which, as you\'ll see, is laughable, because this is anything but easy. - and anyhow, you\'d really be in F whereas the sequence, ultimately should start on the dominant of whatever key you\'re in.)

C: I6 - viio7
---F#: viio4_3 - V6_5 of IV - IV(b7)
------------------B: V6_5 - V7 of IV
---------------------------Eb: Gr6 - V6
---------------------------------Bb: I6

The I6 becomes the tonic of the new key (Bb) which begins the sequence over again until you reach C once more (which, correctly resolving from the Gr6th chord would be the dominant of F, leaving you ultimately in that key.

The cool thing is, if you look, you modulate down chromatically midway through the sequence, so, theoretically, if you wanted, you could get off the ride at any point by either standing in the key you\'re in or using whichever chord as a dominant.

Any thoughts, debates, insights or whatever?

2. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

sorry man, I have no idea what notes you are talking about. What chord system is this?

maybe you could write it out and scan it?

3. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

5 chords,

1. C (in first inversion) (E, G, C)
2. B fully diminished 7 (B, D, F, Ab)
3. F# major w/ flat 7 (F#, A#, C#, E)
4. B major w/ flat 7 (B, D#, F# A)
5. Bb major (in first inversion) (D, F, Bb)

Or, another way to think of it is to take the chromatically descending chords, C to B to Bb, and make it so it works in functional harmony. C is a major chord, B is diminished and Bb is the new key, so major as well.

So, C leads to a B diminished with a tonic/dominant relationship. Then the diminished B chord acts as the diminished 7 of F# instead of C so resolves there instead. Then, F# resolves as a dominant chord to B major (now we\'re in B major) but the B chord, instead of acting as the tonic, via an added flated 7th, acts as a dominant chord. But, surprise, instead of resolving it like a dominant to E, you resolve it like a German 6th to Bb major.

If that isn\'t as clear as mud.....

4. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

Originally posted by Leon Willett:
sorry man, I have no idea what notes you are talking about. What chord system is this?

maybe you could write it out and scan it?
<font size=\"2\" face=\"Verdana, Arial\">Oh, and the chord system is figured bass. I for tonic (Cmaj in the key of C), V for dominant (Gmaj in the key of C), etc., etc....

If you\'ve ever had theory you\'d probably know figured bass. [img]images/icons/smile.gif[/img] But the above post should clarify for those who don\'t know it. [img]images/icons/smile.gif[/img]

5. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

Okay

I have just figured it. Check out the first movement of Scherezede by Rimsky. After the opening statement and violin solo there is a sequence around the main theme where he uses this(if not a very simaliar)movement to change key 5 times. I don\'t have the score here so I can\'t check.

ed

6. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

Sorry

I just checked it out at the piano and it\'s quite different so please ignore me. I will try and work this one out know and get back to you.

ed

7. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

Except for the first C, that progression can be rationalized by the old circle of fifths, with the addition of tritone substitution and inversions.

C
G7b9 (dim7 is just an incomplete 7b9 chord)
F#7 - tritone substitution for C7
B7 - moving by circle of 5ths
Bb - down a half step again instead of a 5th; when a 7th chord moves down a half step, it\'s generally tritone substitution - i.e. the D# and A in the B7 are a substite for A and Eb in an F7, which is the 5 chord in the key of Bb.

The way you hear it, i.e. what key you think you\'re in at any given time, depends on the rhythm.

8. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

Thanks for clarifying.

I did see a bit of figured bass at uni, but we used this kind of notation: C/G (meaning a C majour chord, with G in the bass).

9. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

OK, here\'s my opinion.

I think it\'s an awquard progression, at least to my ears. [img]images/icons/smile.gif[/img] Maybe I haven\'t played it with graceful voice leading, so maybe I\'m not hearing it in its glory. But, it does sound quite awquard to me. [img]images/icons/smile.gif[/img]

The bass moves down a fourth twice in a row. (E-B-F#), and I don\'t like that sound. I also think this movement dissagrees with the general colour of the progression, which is very chromatic and repleat with many \"dark brown\" sounding tritones. I think a bass movement in smaller leaps would be nicer (seconds and thirds).

Also, I find it sounds sort of clumsy to go from B diminished (which at that point wants badly to go back to C, acting heavily as dominant), to B majour (via F#7). Once you assert one chord as dominant (B diminished here), to me it sounds clumsy to suddenly force a \"tonic\" status on that chord. If you are going to do that, I think you need to travel through a few more chords first, so it doesnt feel premature.

That\'s why it\'s quite difficult to modulate to V (like from C to G) without it sounding inconclusive: often it doesn\'t sound like you are modulating, it just sounds like you are resting on the dominant for a while.

So, shoving a majour third on that B (that was diminished a few moments ago) to me feels forced. Also I can\'t find a way for the voices to flow nicely. (but I may be missing something)

The modulation down a semitone from there to Bb I like more, but I must admit it feels like too much is happening in just 5 chords. It would require a slow tempo for my ears to accept Bb as a new tonic. Right now it just sounds like general errant harmony, that would go on and on until finally chilling on a new key.

This is all very interesting. Much more than politics, actually!!! [img]images/icons/smile.gif[/img]

10. ## Re: ORCH: Modulation by whole tone via dim 7th and Gr6

It doesn\'t have to be awkward, in fact it\'s very traditional if you see it as a variation of the old-fashioned extended dominant sequence.

The subtext is that there\'s nothing new under the sun when it comes to harmony! I\'ve come up with progressions I thought were way out there, only to look more closely and realize that it ain\'t jack.