When Playing with relative major's/minor's, and more q's.

[SOA_bassist]

Ok, so lets say I want to play a C major chord on one instrument, but I want to have the other to be playing its relative minor...

First of all, is the relaive minor the note in the middle of the circle of fiths directly opposite of the key you are playing in ( C's minor would be A, F#'s minor would be D#/Eb, etc. )

and Would I play the minor chord of A or the major chord of A? Would it Matter?

A diminished chord is based around a minor third and diminished fifth, right? Does it necessarily need the octave played with it as well?

Also, in the music I am planning on creating, one guitar will be playing heavy stuff ( thrash/death metal ) while the other will almost always be clean. Should I strictly follow chord structures/key for both guitars, or just go by ear? I was thinking a combination of both, but I would like to know what you all thought.

ty for the help =-p =-)

[KayCee]

Originally Posted by SOA_bassist

Ok, so lets say I want to play a C major chord on one instrument, but I want to have the other to be playing its relative minor...

First of all, is the relaive minor the note in the middle of the circle of fiths directly opposite of the key you are playing in ( C's minor would be A, F#'s minor would be D#/Eb, etc. )

and Would I play the minor chord of A or the major chord of A? Would it Matter?

A diminished chord is based around a minor third and diminished fifth, right? Does it necessarily need the octave played with it as well?

Also, in the music I am planning on creating, one guitar will be playing heavy stuff ( thrash/death metal ) while the other will almost always be clean. Should I strictly follow chord structures/key for both guitars, or just go by ear? I was thinking a combination of both, but I would like to know what you all thought.

ty for the help =-p =-)

The rule of thumb for finding the relative minor of a major key is that it is the sixth degree of the major scale. In C, that would be A minor (not A major, which contains a C# note.) Am7 & C6 are actually the same notes, using a different root.

Just for the record, Cmajor on top of A major would be a "polychord" or "bitonal". It would suggest an A7(+9) chord.

Diminished chords need root, minor third, and diminished 5th to be complete. The octave is not neccessary. Adding a min7 (b7) note on top would make it "half-diminished" (min7b5), and adding a dim7 on top (bb7) would make it a "diminished 7" chord.

As far as following traditional chord structures in your writing style, it's your call. Music theory should be used to assist creativity by giving you more tools to work with, never to hinder it.

[DocBop]

I would add that Diminish is one of the two symmetric chords, augmented is the other. Diminished chord every note is a minor 3rd from the other. Take A Dim for example A up a mi3rd C up a mi3d Eb up a mi3rd Gb. Because of this symmetry ANY note of a diminished chord can be the Root. For the "7th" when you go up a mi3rd in our case from Gb you get a Bbb (double flat) or enharmonically a A note. When you see a chart with a Dim7 chord the 7th is double flatted to keep the sequence of minor 3rds. FYI the augmented chord all the notes are a major 3rd apart.

Many diminish chords aren't functioning as diminished they are subbing for dominant chords. Any note of a diminished chord could be the 3rd of a Dominant 7 -9 chord. In fact take your harmonized C major scale. B diminshed is the seventh degree. B is the third of G7 the fifth degree of the C major scale. Music is all math underneath.

As for one instrument playing C major and other playing relative minor A minor. Well theory wise A minor is one of the substitute chord for C major. You have to understand the sound using the substitute will create. In this case it's the note A so it will create a C6 sound. These are more arranging questions. For example are you going to be pedaling C on the bass or going to the A minor. The key is try it so you can hear it and learn the sound for future reference.

[KayCee]

Originally Posted by DocBop

Take A Dim for example A up a mi3rd C up a mi3d Eb up a mi3rd Gb. Because of this symmetry ANY note of a diminished chord can be the Root.

I know what you're saying here, Doc, but I do want to clarify something.

While A, C, Eb, and Gb diminished chords are enharmonically the same (same notes, different order), they are not "interchangable" on a functional theoretical level.

Taking a

Bbmaj - Bdim7 - F/C example.

This diminished chord (probably #4dim in the key of F) is used here specifically to add chromatic voice leading to the bass.
Using

Bb - Fdim7 - F/C is enharmonically the same, but unless you were to actually want that bass root movement, it is much more clear hamonically to use the Bdim7.

And, while the diminished symmetrical scale (whole step, half step) is available in many cases, it is often more desirable to use a scale that implies the diatonic relationship of the diminished chord.

For example:

In Fmaj - F#dim7 - G7 (key of C), the second chord is essentially a non-root D7(b9). Yes, the D7(b9) can be built from symmetrical diminished. Either way, the #IVdim7 and the II7(b9) share identical chord scales.

However, a more diatonic approach would be to keep as many notes in C as possible.

So, our D7(b9) scale would be:

D Eb F# G A B C

That's the V of "G harmonic major"
F#dim7 would be the VII of "G harmonic major"

Now, in theory also, the #9 would be available on the D7(b9) as well, being diatonic to the key. In situations that both the b9 & #9 (with no altered fifth) were desired, you create a non-diatonic, 8-note scale with no given name.

D Eb F F# G A B C

Once you alter the fifth of the D7(b9), it's not a relative of F#dim7. (Edit: Actually, it's still a relative in that they're both still of the subdominant group. However, they no longer share a chord scale.)

[iceshaft07]

Hi; may I ask where you learn all of this stuff? I wasn't aware this kind of stuff existed (certain scales with certain chords, playing relative minors, etc).

I am aware of the 7 scales used, and I am farmiliar with relative minors, but in the two books I am reading, there isn't anything that suggests either of these.

[DocBop]

Originally Posted by KayCee

I know what you're saying here, Doc, but I do want to clarify something.

While A, C, Eb, and Gb diminished chords are enharmonically the same (same notes, different order), they are not "interchangable" on a functional theoretical level.

You are right I was think more of my guitarist days and getting as much out of a chord voicing as I could. So I was think application more than pure theory. Dimished chords get used as passing chords ala the great Freddie Greene in Count Basie's band. Then as substitutes for dominants or alternate voicings might be a better way to put it. The way I learned it was you see lots of diminished chords in old sheet music for Standards and stuff. They really were altered chords, but the type person who bought sheet music wasn't that versed on altered dominants. Also the main instruments of the time were ukulele, banjo and piano. The ukulele and banjo could play the big chords, so sheet music publishers used diminished chords as sub's.

Things get kind of mixed up for me in that I learn most my harmony and theory in Jazz schools and only took a semester or two of traditional theory in college. Then I have studied Improv theory a lot and that is a whole another way to look at same thing. All those things have melted together in my head over the years.

Thanks for clearing things up in my post.

[DocBop]

Originally Posted by iceshaft07

Hi; may I ask where you learn all of this stuff? I wasn't aware this kind of stuff existed (certain scales with certain chords, playing relative minors, etc).

I am aware of the 7 scales used, and I am farmiliar with relative minors, but in the two books I am reading, there isn't anything that suggests either of these.

For me most of this came from studing Jazz theory and Improv classes and books. Traditional books cover same things but usually with different terminlogy. Like Lomento, Tritian chord, and other fancy names.

[SOA_bassist]

some of this was way over my head, but I understood most of it. Thanks for the help guys =-p =-)