Help required with Maj/min 2nd intervals.

[FoonkySteve]

Hi guys,

 

I hope someone can help me get my head round this. Seems i have always had a skewed view regarding this.

 

Intervals within the natural major and natural minor scale:

 

Basically you got 'Perfect' , 'maj/min', 'dim/aug' intervals yeah?

 

Ive got it that Perfect are 1, 4, 5, 8, as they are the same distance from the tonic wether it's a major or minor scale.

 

3rd, 6th, 7th, intervals differ in distance depending on wether they are major or minor.

 

Im cool with that.

 

However im confused about the 2nd. It's always the same distance from the tonic wether it's major or minor, so why isn't it a Perfect interval? To me it can't be defined as major or minor as it is the same regardless of the scale it's from.

 

The reason i ask is; im looking at building sus chords. I have always thought the two sus chords sus2 and sus4 are like 5th chords (intervals) there is no 3rd, 6th, or 7th, to determine thier quality (maj/min).

 

So a sus2 or sus4 could work in place of either a Major or minor chord.

 

Where am i going wrong here?

[JonR]

Where you're going wrong is in defining intervals according to what scale they come from. This works for all intervals except the 2nd, and the reason is that scales are named after intervals - not vice versa - and after one interval in particular: the 3rd.

 

The words "major" and "minor" simply mean "larger" and "smaller", out of two choices. So a major 3rd is 4 semitones, and a minor 3rd is 3. (They're both 3rds because they span 3 notes.)

With 2nds, a major 2nd is 2 semitones between the notes, and a minor 2nd is just 1.

B-C and E-F are minor 2nds.

Looking at each step in a scale - intervals between each pair of notes - there are two minor 2nds in every major and minor scale and five major 2nds - and of course in every mode of that scale..

 

When it comes to the 3rd degree of the scale (measured from the root), that has a very distinctive effect on the sound of the whole scale - just as it does as part of a chord. That's where our whole notion of major and minor scales comes from; and our emotional associations with "major" and "minor" as moods.

The "major scale" (taking its name from its larger 3rd) just happens to be composed of major and perfect intervals only.

But all minor scales have a mixture. In the melodic minor scale, only the 3rd interval is minor; it has major 2nd, 6th and 7th. Harmonic minor has two major intervals (2nd and 7th), and actually has an "augmented 2nd" between 6th and 7th (which inverts to a "diminished 7th").

Phrygian mode is the only scale with perfect and minor intervals only; as measured from the root, that is.

 

None of this has any bearing on sus chords, however. Chord terminology is based on intervals from the root, and not on derivation from a scale. (IOW, scales and chords both derive their terminology from interval terminology. Intervals come first!)

 

A sus4 chord is composed of a perfect 4th and perfect 5th (measured from the root), and a sus2 is a major 2nd and perfect 5th from the root. (There is no need to refer to a scale to build any chord; just an understanding of interval terms.)

When these chords are inverted, btw, they become inversions of each other (which minor and major triads don't do). Eg, C-F-G is Csus4, but F-G-C is Fsus2 (and G-C-F is a partial G7sus4).

 

When harmonizing a major scale, sus4 chords can be built from every degree except IV and vii. (IV has a #4 and vii has a b5.) Sus2 chords can be built from every degree except iii and vii (both chords have a b2).

It's not quite true to say they "work in place of" major or minor chords, because they sound very different - IOW, they're not "substitutes".

[FoonkySteve]

Thanks JonR,

 

Looks like im not going to get away with my 'cheating' methods anymore, im actually gonna have to learn this stuff properly.

 

Thanks a lot for taking the time to reply, im gonna take my time to look over your response, digest and internalise the info.

 

Cheers!

[polishpaul]

^^^^

 

Check through JonR's many posts here - you'll find all you need to know!

[c+t in b]

it has more to do with consonance, dissonance and the ratios that exist between the two pitches. The unison, octave, fifth and fourth all contain small integer ratios, that remain simple when inverted. When heard, this translates to consonance. Hence a perfect interval is a consonance that inverts to a consonance.

 

In contrast, a major 2nd will invert to a minor 7th and a minor 2nd will invert to a major 7th which are varying degrees of mild consonance and harsh dissonance

[sfarfsky]

 

Where you're going wrong is in defining intervals according to what scale they come from. This works for all intervals except the 2nd, and the reason is that scales are named after intervals - not vice versa - and after one interval in particular: the 3rd. The words "major" and "minor" simply mean "larger" and "smaller", out of two choices. So a major 3rd is 4 semitones, and a minor 3rd is 3. (They're both 3rds because they span 3 notes .) With 2nds, a major 2nd is 2 semitones between the notes, and a minor 2nd is just 1. B-C and E-F are minor 2nds. Looking at each step in a scale - intervals between each pair of notes - there are two minor 2nds in every major and minor scale and five major 2nds - and of course in every mode of that scale.. When it comes to the 3rd degree of the scale (measured from the root), that has a very distinctive effect on the sound of the whole scale - just as it does as part of a chord. That's where our whole notion of major and minor scales comes from; and our emotional associations with "major" and "minor" as moods. The "major scale" (taking its name from its larger 3rd) just happens to be composed of major and perfect intervals only. But all minor scales have a mixture. In the melodic minor scale, only the 3rd interval is minor; it has major 2nd, 6th and 7th. Harmonic minor has two major intervals (2nd and 7th), and actually has an "augmented 2nd" between 6th and 7th (which inverts to a "diminished 7th"). Phrygian mode is the only scale with perfect and minor intervals only; as measured from the root, that is. None of this has any bearing on sus chords, however. Chord terminology is based on intervals from the root, and not on derivation from a scale. (IOW, scales and chords both derive their terminology from interval terminology. Intervals come first!) A sus4 chord is composed of a perfect 4th and perfect 5th (measured from the root), and a sus2 is a major 2nd and perfect 5th from the root. (There is no need to refer to a scale to build any chord; just an understanding of interval terms.) When these chords are inverted, btw, they become inversions of each other (which minor and major triads don't do). Eg, C-F-G is Csus4, but F-G-C is Fsus2 (and G-C-F is a partial G7sus4). When harmonizing a major scale, sus4 chords can be built from every degree except IV and vii. (IV has a #4 and vii has a b5.) Sus2 chords can be built from every degree except iii and vii (both chords have a b2). It's not quite true to say they "work in place of" major or minor chords, because they sound very different - IOW, they're not "substitutes".

im gonna need some metamucil to digest all of this

 

to recap what I learned: major means bigger, minor means smaller. makes perfect sense. will come back later

[Gaetano Paul]

Killer post JonR, clear & concise

[1001gear]

im gonna need some metamucil to digest all of this to recap what I learned: major means bigger, minor means smaller. makes perfect sense. will come back later

 

 

lulz

 

per the question he's just saying that major scale have whole step to start

and minor scale have WHOLE step to start.

 

See how that works? It's not until Phrygian and Locrian do you see that half step at the bottom.

[polishpaul]

It's worth spending some time on scale steps. My understanding expanded when I read about looking at the major scale in two halves, eg:

 

C D E F

G A B C

 

The top line is the first half of C major, and the bottom line the first half of its dominant, G major.

 

Continuing this we come to:

 

D E F G

A B C D

 

....which is, in the same way, D minor on top and A minor on the bottom. We now have enough for a jazz improvisation. Figure out the seventh and major seventh of each chord, from the notes we already have, and we're away!

 

It becomes clear that the third of the dominant is the seventh, sometimes flatted, of the tonic........and that we are progressing through the circle of fifths.

[1001gear]

Those are called tetrachords in some circles.

[gennation]

It's worth spending some time on scale steps. My understanding expanded when I read about looking at the major scale in two halves, eg: C D E F G A B C The top line is the first half of C major, and the bottom line the first half of its dominant, G major. Continuing this we come to: D E F G A B C D ....which is, in the same way, D minor on top and A minor on the bottom. We now have enough for a jazz improvisation. Figure out the seventh and major seventh of each chord, from the notes we already have, and we're away! It becomes clear that the third of the dominant is the seventh, sometimes flatted, of the tonic.... ....and that we are progressing through the circle of fifths.

 

Those are tetrachords. Most of all of our common scales and their modes are based on stacking tetrachords. I have a great tutorial on stacking tetrachords here: http://mikedodge.freeforums.org/tetrachords-what-you-didn-t-know-you-already-knew-t18.html

[polishpaul]

 

Those are tetrachords. Most of all of our common scales and their modes are based on stacking tetrachords. I have a great tutorial on stacking tetrachords here: http://mikedodge.freeforums.org/tetrachords-what-you-didn-t-know-you-already-knew-t18.html

 

 

I wasn't thinking as far as playing them as chords, only at scale level, so I'll check this out. Thanks!

[polishpaul]

Those are tetrachords. Most of all of our common scales and their modes are based on stacking tetrachords. I have a great tutorial on stacking tetrachords here: http://mikedodge.freeforums.org/tetrachords-what-you-didn-t-know-you-already-knew-t18.html

 

This is indeed a GREAT tutorial....a MUST read!

 

I saw it a couple of years ago but wasn't ready for it back then - "Oh no, not more theory. There's no end!"

 

So I passed it by. If you're not ready for it, make sure you bookmark it for when you are!

 

Funny, but my post here looks like a resume of the tutorial, even down to the examples used . Something from it may have stuck in my subconscious, but I wrote the post without recent reference to it.

 

I'm rather proud of myself .

[1001gear]

Means something like 4 notes. I've never heard it discussed as harmonically stacked chords. I'm sure Genn's lesson will make all that clear.

[JonR]

I wasn't thinking as far as playing them as chords, only at scale level, so I'll check this out. Thanks!

A "tetrachord" isn't a chord . It just comes from the Greek for "four string", and refers to the ancient Greek lyre and the way it was (supposedly) tuned. In our sense, it's simply a group of 4 consecutive scale notes, normally spanning a perfect 4th.

The Greeks built their modes by stacking different tetrachords - as mike explains.

[c+t in b]

Tetra chords can absolutely be chords. They are usually taught as fragments to show a breakdown of scales. However, they are chords by seconds, or to some extent, clusters. You can build a chord by seconds in the same exact way that you can build a chord by thirds and fourths.

[polishpaul]

 

Tetra chords can absolutely be chords. They are usually taught as fragments to show a breakdown of scales. However, they are chords by seconds, or to some extent, clusters. You can build a chord by seconds in the same exact way that you can build a chord by thirds and fourths.

 

 

I've just read about the fingering problems for guitarists in forming these chords in standard tuning. I suppose it's easier for a pianist to use them. Could you expand on this concept of chords by seconds and their use, please?

[JonR]

Tetra chords can absolutely be chords.

Yes, in the way you say. Any bunch of notes can be a "cluster", if we can define a cluster as a "chord" (which is debatable IMO). (How would you define or name a chord built from the notes C D E F?)

 

But generally a "tetrachord" isn't a chord as we know it: the "chord" part of the word just means "string". In the same way that "monochord" means "one string". (Not a one-note chord )

Essentially - in most common usage - a tetrachord is 4 consecutive notes of a scale.

[polishpaul]

C D E F?

 

An inversion of Dm9?

[polishpaul]

Oddball voicing of Dm9?

 

(This is how we learn....)

[JonR]

 

Oddball voicing of Dm9? (This is how we learn....)

A partial Dm9, sure. But - because it misses the 5th (A) - to actually sound like Dm9, it would need to be voiced with D on the bottom. IOW, you'd need to break the tetrachord.

C D E F in that order is a "tone cluster"

http://en.wikipedia.org/wiki/Tone_cluster

 

The idea of using names like "Dm9" derives from chords built in 3rds, or rather alternate steps counted from a root (3rd-5th-7th etc). Chords built in any other way are difficult or impossible (or pointless) to name using that system. (We have to reconstruct the chord so the notes fall into 3rds, which may not be appropriate if it makes the chord sound siginficantly different.)

 

In this case, you could re-arrange the notes to sound like a partial Dm9, or maybe a partial Fmaj13. It could even be a rootless G13sus4. I was going to add that this is somewhat academic for guitarists who can't generally play 4 adjacent scale notes (n standard tuning), but in fact we can play this cluster as follows:

 

-0--

-6--

-7--

-10-

----

----

 

A couple of not too difficult moves (or retuning!) will even let us hear that with a D bass or G bass. But on its own I don't think it has a chord identity we could reliably name.

[polishpaul]

Thanks, Jon!

 

I just tried that chord on classical and it sounds haunting and harp-like (big string harp, not harmonica)....I'd say it has potential. I must find more of these sounds with the open strings - I've been doing them lower down but not so far up on the fretted notes till now.

 

Luv LL

[c+t in b]

a fifth is the most useless and easily dismissed note in a seventh chord. you do not need it to define it's quality

 

It would also be more of a 3rd inversion D minor 7 add 2, since the E is a major 2nd above the root.

 

Or D-7 (add2)/C

[JonR]

It would also be more of a 3rd inversion D minor 7 add 2, since the E is a major 2nd above the root. Or D-7 (add2)/C

Right! (The awkwardness of the symbol illustrates the limits of our tertian naming system in dealing with chords constructed in anything but 3rds.)

That describes it about as well as any symbol could, but still without specifying that precise voicing.