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I am writing in Cm and want to modulate smoothly to Gm and then smoothly back to Cm. Can someone please tell me what is the best way to do this. I see that it is the 4th degree in the scale that must be raised just like in major to create a leading tone to Gm, so I could just go from Cm to D and then down a 5th to G but what other ways are there? I suppose all inversions of D7 would also work too right? How about using bVII7 to bVII42 but instead of resolving to III6 resolve to Gm? would this work? please share alternative ideas as Im sure you can do loads of things. Do you always have to alter two notes to modulate in minor? It seems that the ii° chord would need to have two tones altered to create a dominant chord so I bet that this makes the modulation sound less smooth than im major.

Then to get back it is the 3rd of Gm that would need to be raised to form a leading tone to C right? This would mean making i into a major chord... not sure I like that sound, what else might work?

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4 Answers 4

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The textbook thing to do is play a chord common to the two keys, called the pivot chord, then play the dominant of the next key.

Cm to Gm should be relatively easy, because Cm is a chord (Gm:iv) in Gm.

So, Cm G7 Cm - something like that, elaborate any way you like, will establish Cm as the first key. Then do Cm D7 Gm to modulate to Gm.

Yes, to go back, using normal tonic/dominant harmony, the Gm will become a G or G7. Regarding the pivot chord of textbook modulation, there is nothing special to do to go from Gm back to Cm, because Gm is diatonic to Cm, so just playing Gm provides the pivot. Just do Gm G7 Cm and you're back to Cm.

How about using bVII7 to bVII42 but instead of resolving to III6 resolve to Gm? would this work?

Sure, you could use a deceptive progression. You can also use augmented sixth chord resolutions to modulate. You can just directly introduce the dominant of the next key, etc. etc. But those things by (textbook) definition are not smooth. They would be more like surprise moves that emphasize the chromatic color. The textbook "smooth" modulation tries to exploit what is diatonic and minimize the chromatic. In essence that is what make the smoothness.

This would mean making i into a major chord... not sure I like that sound, what else might work?

I think you mean the mode change of Gm G7 is what you don't like and want to avoid. Just choose a different chord as the pivot. Technically, Cm would be the most obvious common chord, so Gm Cm G7 Cm will give you a diatonic pivot and separate Gm from G7 by one chord.

The modal chords (as typical pivot chords) and the circle of fifths progression are another strategy. From Gm you could get to E♭ any number of ways and then just follow a circle of fifths progression into Cm: Gm ... E♭ A♭ Dø7 G7 Cm.

Considering modal chords and how they can be used in modulation, the ♭VII in minor should be understood to have that strong modulating potential. Tonally it alters the leading tone, which weakens the tonality. It also introduces the subdominant degree of the subdominant key. In other words, it isn't merely an alteration of a sharp or flat, but a tonal alteration of that pitch's function from dominant in the one key to subdominant of another. Therein lies the modulation implications.

So, another option for smooth modulation, using a pivot chord, and avoiding the direct modal change of Gm G7, can be had through ♭VII. Something like Gm: i v6(min) stays diatonic to Gm while also introducing the subdominant, tonal degree of Cm, technically it isn't a pivot chord, but the new subdominant degree does a lot to begin shifting the tonality, continue as Gm i v6 iv6 and we get to the Cm pivot chord, then continue, we played the pivot chord so now we are free to play in Cm, using the subdominant both makes for emphatic functional harmony in the new key and is consistent with how we departed from Gm, Gm: i v6(min) iv6(Cm: i6) Cm: iiø7 (or iv) V7 i.

You could do many other things.

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  • OP has already considered D (D7).
    – Tim
    Commented Aug 30, 2022 at 14:05
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    I'm confirming he's found the smoothest, textbook way. Beyond that, listing out alternatives is off topic. An open ended list. Commented Aug 30, 2022 at 14:07
  • I like the circle of fifths idea. If I use that however by introducing Ab in Gm arent you already in Cm again because Ab is not in Gm? So from Gm if I just go to Eb and then instead of going down a tritone to ^2 which would be the diminished ii chord, I go down a fifth like you said to Ab and there in istelf is a modulation right?
    – user35708
    Commented Aug 31, 2022 at 7:26
  • Gm E♭ will be in G minor, with E♭ being the pivot chord belonging to both G and C minor. That's the ambiguity of modal level chords, A♭ will indeed bring in harmony unique to C minor, the G7 will eventually make the modulation emphatic, but we were trying to separate the Gm chord from G7, so delaying the G7 with a circle of fifths was intentional. Commented Aug 31, 2022 at 13:18
  • I think the thing you want to understand is modulatory passages are considered tonally ambiguous, and the decisive point of modulation is normally a cadence in the new key. So, passage E♭ A♭ Dø7, after have established G minor, would be the ambiguous part. Sort of like "are your sure what key you're in?", then continuing with G7 Cm provides the cadence to confirm a modulation. Sort of like "yes, I meant all those not G minor chords, because I changed key on you!" Commented Aug 31, 2022 at 13:24
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C diminished will be one way - diminished chords are always a good way to modulate, and two of the notes are common to Cm as well as the G♭ posing as leading note F♯ to Gm.

Returning I would use G7, from the parallel key of C major, but in any case, the V of quoted original Cm. Thankyou JB.

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  • @JohnBelzaguy - caught me out! G7 doesn't belong to key G major. I meant 'the parallel key of C major' - parallel to the quoted Cm key - of course! And also belonging to Cm anyway. Standing in the corner with that pointy hat on already!
    – Tim
    Commented Aug 30, 2022 at 14:45
  • do you mean going from Cm to C°7?
    – user35708
    Commented Aug 30, 2022 at 14:53
  • Coming from you that made me scratch my head, lol. No need to list me in the liner notes, I’ll delete my first comment. Commented Aug 30, 2022 at 14:55
  • @armani - yes, I do. Or even just Co triad.
    – Tim
    Commented Aug 30, 2022 at 14:55
  • @JohnBelzaguy - we don't appear to have 'hapears' on the right of the Atlantic. Although we do scratch a lot of things. Enlighten, please. Leave the comment - it makes me look human...
    – Tim
    Commented Aug 30, 2022 at 14:57
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Is this for a textbook exercise where 18/19th century practice is required? Or for something you're composing now?

Either way, there are two approaches to a modulation. The one where you want to slip imperceptibly into the new key, and the one where modulation is for dramatic effect and you WANT it to be noticed! You're looking for the imperceptible one? OK.

These days (and quite a lot those days, if not in our harmony textbooks) C minor is as likely to include a Gm chord as it is a G major. (In fact, there's an assumption in many of the questions on this forum that the Natural Minor is the norm, whereas my generation was taught that the Harmonic Minor, with its raised leading note enabling a 'proper' dominant chord was standard.)

If you're writing today's music, I think the best plan is the Nike Modulation, 'just do it'. The B notes in your C minor section were quite likely B♭ already, there's no expectation that G minor will be defined by the introduction of F♯. C minor and G minor are so close. Just stop writing A♭s and structure the melody around G instead of C.

If you're trying to channel Mozart, I guess you want to throw a D7 chord in there. Maybe preceded by an Am7, or Am7♭5.

I'll leave you to name the chords in my examples!

enter image description here

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Some great ideas and answers here. After much experimentation and trying out all these little nuggets I would like to post my own anwser. I find that the absolute smoothest modulation up the circle of fifths in a minor key (from Cm to Gm) is via the raised scale degree ^6. Introducing this scale degree first is very easy and brings us into the same accidental territory as Gm (2 flats) meaning that any secondary dominant chord that resolves to Gm introduced thereafter will only need one accidental as opposed to 2. By first introducing raised ^6 and then moving to a V/v chord, you effect the modulation into two steps making it sound much smoother than if you introduce both in the same chord (such as is the case if you just use a straight secondary dominant chord like D7 or its inversions). I really like the sound of this because to my ears, the V/V chords in major sound so much smoother than in minor for this specific reason. In major you are only raising scale degree ^4 but in minor you have to raise scale degree ^4 and lower scale degree ^6 to get your secondary dominant chord. This to me sounds more abrupt.

Then to go back to Cm I find it helpful to think about how one can introduce the one note that would lower us down the circle of fifths and that note is b2. I like the idea of cushioning our hearing into the new key area without the use of a dominant chord so that when and if you do use it, it sounds like you are already in the right key. Michaels idea of going via the submediant and then down a perfect fifth to b2 is very nice sounding and I like that option a lot but I can think of a lot of other ways to introduce the b2 note and I think by doing so you already are hearing Cm again so no dominant chord is even necessary.

In short, raised ^6 to go up and b2 to go down, these are the key notes that shift us one up and own down the circle and I find it really helpful to think along those lines

Here is a progression I wrote.. the soprano is boring but you get the idea enter image description here

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