music theory nerds

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just a good guesser
Member Since: Oct 04, 2004

first, my question is, how does one switch from key to key in chord progressions. i want to be able to switch keys to keep the song interesting. here's an example:

i'll use the roman numeral system so i'll be able to understand.

the progression in the key of C/Am is C F Am G7 (roman numerals are I=C, IV=F, ii=Am, V7=G7)

the key i want to switch to is the key of G/Em with the same progression as the outcome (I-IV-ii-V7) .

so, what would you do in order to make the switch, so that it sounds nice?
if you could explain your reasons why you chose the path you did would help also.

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just a good guesser
Member
Since: Oct 04, 2004


Aug 29, 2005 10:26 pm

correction the chord progression is I-IV-vi-V7 with Am as the vi.

we prefer "percussionist"
Member
Since: Jul 21, 2004


Aug 31, 2005 05:38 pm

Dominant modulations (going from I to V) are so consonant they usually don't need any steps to bridge in between. Schoenberg would say it "requires no energy" to jump between the keys. And, since you're ending in G7 anyway, you're already there. You could either resolve back to I, or just hold out the G for 2 bars, drop the 7th in the second bar, and there you are.
So, you're looking at either:
C-F-Am-G7-C-G-C-Em-D7
or
C-F-Am-G7-G-C-Em-D7

9 times of 10 I'd opt for the second, but I like "unfinished" sounding cadences, especially for moving into a bridge section - kinda makes it sneak in almost unnoticed. Now that I think about it, I would probably even just go straight to G the last time through the progression and cut the whole G7 out that time around, if it worked melodically.

Member
Since: Jan 18, 2003


Sep 02, 2005 02:02 am

i will recommend at least trying out a secondary dominant...this is a pretty common trick that i need to use more, but it usually sounds good. might give you a radiohead or beatles feel.

after the last G7 in the progression, play D7, which is the V7 of V.

i dont know if you've run into this idea before. ill try to explain a bit.

G7 is the V7 of C when youre in the key of C. it is the only dominant 7 chord in the key of C. you are allowed to use the dom7 chord of the new key you're about to move to, in order to set up the new I chord via the most obvious, powerful chord in diatonic harmony in terms of defining the key--the V7.

so...if you want to modulate the key of the song to G, you can exploit the fact that the V7-I progression is, to the ear, the strongest, most key-affirming chord shift you can do, and you can prematurely reach into the key of G major and grab that D7--maybe only playing it for a moment--and then go back to G. doing this, youre doing V7-I in the new key. it should sound, i think, a little bit energetic, like something's leaning over a weird precipice, then it should come back down to a new place and be satisfying. your ear will expect a d minor triad (since youre still in the key of c), but you'll provide a d major instead, which should sound momentarily odd, but then should recontextualize the g chord and instantly make it sound like the I instead of the V (as it does in the key of C).




Member
Since: Jan 18, 2003


Sep 02, 2005 03:44 pm

it should also work if, on the final repetition of the section, you substitute D7 for the G. just dont even hit that last G, but use D7 instead. then go to G, and it will sound like the home key.

i tried this stuff last night on the piano a bit, because i want to understand secondary dominants. i found that:

1. this technique sounded better, all in all, when the chords were broken into arpeggios and when good voice leading was used. to accomplish good voice leading, i used inversions of the chords instead of the root forms, and used the inversions that led to the least amount of finger movement between chords.

2. ending the section with G, then going to D7, then back to G for the start-over in G only sounded right when i did a certain thing: ended the section with G and then D7, splitting the measure between them. in other words, making the 'final chord' of the section two chords with half-time for each.


while i like the progression, i dont fully like the results of this, because i think that the key change to G is not my cup of tea. why did you choose that key?

Member
Since: Jul 02, 2003


Sep 04, 2005 01:44 pm

I find the theory of music very interesting but most of it goes over my head faster than an F/16.

I think I have songs that change keys, but couldn't tell you which ones, how or why I resolved them the way I did other than the way they sound.

Dan

Member
Since: Jan 18, 2003


Sep 05, 2005 12:29 pm

does anyone know if you can use secondary dominants as a sort of hinge for a key change? i mean, im not sure they're enough. but i'm about to start reading shoenberg's structural foundations of harmony as soon as someone explains figured bass to me (andrew? can ya?) cause it's high time i went through another theory phase.


Member
Since: Jan 18, 2003


Sep 05, 2005 12:30 pm

dan how much have you looked into theory? i forget

Member
Since: Jul 02, 2003


Sep 05, 2005 04:01 pm

Not a whole lot forty. I have the basic rudiments I learned when I was young and everytime a thread like this pops up I usually go and read up some on the subject. I spent a couple hours after this post reading stuff on keys and changes etc, but one really needs to start at the beginning to really get alot out of it. :)

Dan

Member
Since: Jan 18, 2003


Sep 05, 2005 09:11 pm

ah, i bet your teachers taught you the hard way like mine did, like memorizing the number of sharps in all keys and that sort of thing.

Administrator
Since: Apr 03, 2002


Sep 05, 2005 09:14 pm

theory schmeory...just rock out.

Never had a music teacher personally, or, not one I paid attention to...in fourth grade I tried band instruments cuz I wanted to learn music, the band director said something to the effect of "don't quit your day job"...so, well, that was the end of any formal education in music I ever had other than waste-of-time music classes that I had to take in elementary, but I never paid attention in those anyway...

Member
Since: Jul 02, 2003


Sep 05, 2005 10:06 pm

I agree theory isn't neccessary to create good music and I certainly don't know enough of it to do me much good at any rate... <G> but I do find it interesting in the why's and how's things are done the way they are, besides "oooh that sounds cool" LOL.

Dan

Member
Since: Jul 02, 2003


Sep 05, 2005 10:10 pm

Yep, they tried anyhow forty. lol I've forgotten most of what I did learn. But I can still read music very slowly at least. :)

Dan

Member
Since: Jul 25, 2005


Sep 06, 2005 06:27 am

i think andrews idea works fine . . . you could also play a (G triad) instead of a G7 when you wanna change to the key of G . . . example: C/F/A-/G7/C/F/A-/G/G/C/E-/D//

Member
Since: Jan 18, 2003


Sep 07, 2005 01:36 am

i think you need to change to a slightly more tense key. ii, maybe. or bVII

just my opinion, and im drinking and dont clearly know how those changes would sound. going to g from c, though, is the most ... whats the word i want...congenial? change possible. i dont see how it serves to move the progression to a new energy level. especially because the key of g uses nearly all the same chords as c.


just a good guesser
Member
Since: Oct 04, 2004


Sep 07, 2005 08:35 am

hey thanks all for the help

we prefer "percussionist"
Member
Since: Jul 21, 2004


Sep 09, 2005 12:30 pm

Sorry, been off line for a bit...

Fortymile - I've heard of using secondary doms. to transition before, but I don't use it too much, personally. It kind of feels "jerky" to me, like you're hitting two key changes instead of one. That's just me though. I think for a "by the book" answer they work fine.

Re: Figured bass
The numbers are the intervals above the root used in the chord, so if it says (from bottom to top) 3-5-7, and you're in C, you would play C (root) E (3rd above C ) G (5th above C) and B (7th above C). In actual use, the 3 and 5 are assumed to be there, so they usually aren't written, so it you see a 7, it's an added M7th, if you see a 6, it usually replaces the 5. It's really the same as modern chord symbols, just without the letter name.

Theory's great if you use it to make your life easier (knowing where to go instead of hunt-and-peck composition), but don't let it get in the way of your ears and your heart.

Member
Since: Jan 18, 2003


Sep 09, 2005 03:18 pm

can you give a few more examples? having a hard time understanding that. the reason i need to know is that i wont be able to get as much out of the schoenberg book im about to read unless i know exactly how to untangle figured bass symbols. well, i guess i can look it up online. but if you feel like it...

as for sec. doms as doorways to other keys, i saw some sources saying that they were used more as momentary 'setups' to other chords within that key that youre already in. gotta do some more checking on this; i thought they were also frequently used to change keys, but i forget what i dont use, so...


we prefer "percussionist"
Member
Since: Jul 21, 2004


Sep 21, 2005 04:23 pm

Really, you shouldn't need to know too much about figured bass for any Schoenberg, he doesn't use it that much. He considered it outdated and impractical. For the few times he does use it, though...

The note written on the staff is your chord root, "1". The numbers below the staff refer to intervals above the root, so if it says 3-5, you're playing a standard triad (1-3-5). If you've got a C, and it says 4-6 underneath, you play C-F-A, an inversion of F maj. If it says 3-5-7, you play C-E-G-B, a CM7.

That any more clear?

Member
Since: Jan 18, 2003


Sep 21, 2005 06:39 pm

yes thanks. makes you do an 'extra step' though, as you try to determine whether that written note is the root or whether youre playing an inversion. i no likes!


Member
Since: Aug 26, 2005


Sep 22, 2005 12:15 am

One way to help substitutions sound smoother is to invert the chord e.g. play the third or seventh in the bass if that helps the bass be more melodic as in moving by step or third instead of jumping a fourth or fifth.

As far as modulation goes there are direct modulations and pivot chord modulations. Direct modulations can even be to keys that are a chromatic mediant apart.

Another example of a pivot chord is the neopolitan. When you come to ANY major chord consider that the b2 of the new minor key and then progress down a half step to a minor chord. This minor chord can be the minor i of the new key or it can be the minor ii in a ii V i or ii V I progression.

Some general concepts that you won't usually find in a theory book but which are frequently exploited; A major chord can progress to any other major chord or key. A minor chord can progress to any other minor chord or key.

Also, we all know that the I, IV and V can have major chord even if the melody is minor pentatonic but there's a thing called Beatles harmony which extends that to build major chords on the bIII and bIV as well to give more options in the chord progressions.

More later,

Gongchime

Member
Since: Jan 18, 2003


Sep 22, 2005 12:53 am

the bIII and bVI have been around for a lot longer than the beatles. and today they're part of any songwriter's composite chord set.

nice tip with the neapolitan. i wanna use the N chord more.

by chromatic mediant, you mean a major third?



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