"Dissonant" Intervals?

[AlsoRan]

Are there certain intervals that are pretty much always categorized as being "dissonant." For instance, a b7 does not sound too good played over a chord a chord with a major 7th. Can you suggest some other intervals that pretty much never sound good when played at the same time for certain length of time.

Note I am aware that over a given chord, you can play outside notes and some REALLY outside notes as long as you play them swiftly and don't dilly dally or linger too long.

Also, as you have taught me, there are no real rules in Jazz, but I am asking this according to traditionally accepted practices. Thanks.

[merritt stone]

Intervals are different than the way any given note sounds against any given chord. That's harmony.

[AlsoRan]

You are right. Merritt.

I need to modify the question.

Are there any two notes, a given interval apart, that are considered dissonant? For example, a minor second interval?

(I finally have time to play my guitar and am going to try them all right now to see if I can answer my own question!)

[merritt stone]

Minor 2nds and diminished 5ths (tritone) are the only intervals that ever sounded really dissonant to me. Actually, even a major 7th has a dissonant sound as well, when played without a 3rd or 5th. I've never been schooled in classical theory, so I can't speak for any textbook answers, but I can use my ears!

Here's a more formal Wiki on the subject:
Consonance and Dissonance - Wikipedia

[timscarey]

IMO the most dissonant interval is the minor 9th. So, like C up to Db it really only works if its between the root and b9 of a dominant, it pretty much all other cases, it sounds like ass. Again, just my opinion.

[JakeAcci]

Originally Posted by timscarey

IMO the most dissonant interval is the minor 9th. So, like C up to Db it really only works if its between the root and b9 of a dominant, it pretty much all other cases, it sounds like ass. Again, just my opinion.

even that...I think there are some really pretty uses of a m9 interval. Certain inversions of maj7 or m9 chords are pleasing to me in a 'modern' sense:

4
5
4
4
6
0

3
3
2
4
2
0

completely subjective though.

[JonR]

As timscarey says, the minor 9th is the one interval that is considered most dissonant, most of the time (except in a 7b9 chord). Not just his opinion, but conventional jazz opinion. Any time you see the concept "avoid note", you can bet they're talking about a minor 9th interval. (Ie, it's always a half-step above a chord tone, with the implication that it could or would have an octave between.)

The minor 2nd might seem dissonant, but in fact it can sound perfectly good in certain contexts - eg, between 2nd and 3rd of a m9 chord, or m(add9).

Eg in these voicings:

Emadd9
-0-
-0-
-0-
-4-
-2-
-0-

Am9
-0-
-0-
-5-
-5-
-0-
-0-

To be more precise, perhaps, there is clearly dissonance there, but not an unpleasant one. IE, it's useful to make a distinction between nice dissonance and nasty dissonance . (Maybe call the latter "discord", although that's still an arbitrary distinction.)
Pianists, too, might often voice maj7 chords as 5-7-R-3, with the half-step in the middle (and of course that's a good voicing for a rootless m9 chord .). But they would not put the root an octave higher, to form a b9 with the 7th.

Jazz uses all kinds of "nice" dissonance that classical ears might find "nasty" - or at least confusing. Eg ending a song on a maj7 sounds "unfinished" to classical ears. To jazz ears, does it sound "finished"? Or do we just like that "unfinished" sound?
(Likewise there might be many advanced classical harmonies that sound "nasty" to jazz ears.)

As merritt stone says, context is all when it comes to most dissonances. The tritone and maj7 are pretty stark on their own. But in the context of the right chord, both are quite acceptable, even smooth.
The tritone in a dom7 chord remains a significant dissonance, but it's a functional one: ie it's OK because it sounds familiar and we know what it's for, where it's going (how it's going to resolve). Similarly (for possibly different functional reasons) in a m7b5 or dim7 chord.
The maj7, meanwhile, is softened considerably by forming strong consonant intervals with 3rd and 5th in a maj7 chord; they take the sting out of the interval it makes with the root.
We get a maj7 between the 3rd and #9 in a 7#9 chord - a different kind of dissonance, but acceptable because it's a blues sound (at least in a tonic chord). As V7 chord in a minor key, its tension becomes (again) acceptable because of a clear functional purpose.

[cmajor9]

Don't confuse "dissonant" with "bad." Its more useful to think:

dissonant = tense
consonant = relaxed

In terms of intervals, octaves, fifths, and thirds (and their inversions) are more on the consonant side, while seconds and tritones are on the dissonant side. Again, sometimes you want that tension, and these intervals sound "dissonant" but "right" in that situation.

As others have pointed out above, a bare major 7th or minor 9th sound very dissonant, even "harsh", but in the context of certain chords (Ima7 or Vb9) these intervals find a satisfying context. In other contexts they would sound "outside" or out of place. The same is true with tritones.

[JakeAcci]

Originally Posted by JonR

But they would not put the root an octave higher, to form a b9 with the 7th. .

Sure they would, just not as often, and generally at a point probably to create a certain effect.

[JonR]

Originally Posted by JakeAcci

Sure they would, just not as often, and generally at a point probably to create a certain effect.

OK, but as part of a chord voicing, it's still generally considered an "avoid note", yes? That's my point here.
All kinds of dissonance (even the nastiest) are available as effects.

[JonR]

Originally Posted by cmajor9

Don't confuse "dissonant" with "bad." Its more useful to think:

dissonant = tense
consonant = relaxed

My point exactly. The issue then is "How tense is too tense?" (in any particular context).
Or indeed "how relaxed is too relaxed"

[bako]

Although it is necessary to use discretion and understanding to make effective use of certain intervallic colors, in my opinion it is important to know the sound of every intervals individually and in as many harmonic contexts as possible. Never avoid learning a sound just because it might present problems.
Every interval is used in music.

[AlsoRan]

You guys have done it again. Thanks for sharing.

[AmundLauritzen]

Dorian b9 is a common melodic minor application. You can also use the #11/b5 on m7. But as stated, how consonant or dissonant something sounds has a lot to do with what you play before and after.

Another cool sound is to use the m6th in conjunction with the m3rd on minor chords. It creates a dissonant tritone.

Also, the major 3rd can sound really cool on minor chords when used in a confident and appropriate way.

The hardest interval to make music out of is the #7th on dominant chords IMO. I've heard some players make this interval sound great in that context, and I'm not talking about using it as a passing tone as in a bebop dominant scale. It can be used in a wider intervallic way. When you establish a wide intervallic sound, you can throw in a lot of "illegal notes" because of the organized chaos(the intervallic structure makes a cohesiveness).

Pat Martino does some octave displacement of the chromatic scale. That would be going up a m9th for each step C to C# then down to D and up a m9th to D# and so on. Another way of organizing chaos.

[jayv999]

There's an interesting article on Intervals by Ted Greene on his website.
TedGreene.com - Teachings - Fundamentals
--Jay

[AlsoRan]

Originally Posted by jayv999

There's an interesting article on Intervals by Ted Greene on his website.
TedGreene.com - Teachings - Fundamentals
--Jay

Thank you for this!

It was really valuable to me - one man's (albeit a great man) view on intervals and dissonance.

What really hit home was his reiteration of what was already written earlier in the thread - dissonance is not always "ugly," or offensive. It can be just restless or incomplete.

Good find!

[cosmic gumbo]

The tritone is such an evil dissonance it is called "Diabolus in Musica".

[BigDaddyLoveHandles]

Originally Posted by cosmic gumbo

The tritone is such an evil dissonance it is called "Diabolus in Musica".

Awesome tat', dood!

[JakeAcci]

Originally Posted by bako

Although it is necessary to use discretion and understanding to make effective use of certain intervallic colors, in my opinion it is important to know the sound of every intervals individually and in as many harmonic contexts as possible. Never avoid learning a sound just because it might present problems.
Every interval is used in music.

Exactly.

The statement "b9 intervals are typically only used in contexts X, Y, and Z" is useful as a point about history and stylistic tendencies, but learning to hear each voice of various voicings and voice-led progressions is directly useful in making harmonic decisions when composing or improvising.

I think one of the worst things that occasionally happens in musical education is spreading an idea that a certain sound should always be avoided, or even treated with more caution than another sound. Innovations are made by hearing things in new ways.

[JonR]

Originally Posted by cosmic gumbo

The tritone is such an evil dissonance it is called "Diabolus in Musica".

Correction, "was". About 1000 years ago, roughly. And they didn't think it was literally evil even then.
(Of course, it's still fun - if you like that kind of thing - to imagine it might be.)

[JonnyPac]

Originally Posted by timscarey

IMO the most dissonant interval is the minor 9th. So, like C up to Db it really only works if its between the root and b9 of a dominant, it pretty much all other cases, it sounds like ass. Again, just my opinion.

I agree with Tim 100% here. I can't believe how teachers push drop-2 maj 7th chords with the M7 on the bottom and the root on top- It sounds like ass, IMHO.

I even dig inverting dom7b9 chords so the root is above the b9. Set against the bassist, the dissonance is de-emphasided. Here's a wickedly awesome E7b9 voicing set up that way:





-12--------------------------------------------
-9--------------------------------------------
-11--------------------------------------------
-9--------------------------------------------
---------------------------------------------
-(0)--------------------------------------------

[bako]

common sequence

C-------------CMa7--------C7-------------FMa7--------Fm6-----------Cadd9
C-E-G-C-----B-E-G-C-----Bb-E-G-C-----A-E-F-C-----Ab-D-F-C------G-D-E-C

lydian C Major Vamp

CMa9#11-----CMa7--------CMa6/9-------CMa7
D-F#-G-C-----B-E-G-C-----A-D-G-C-----B-E-G-C

upward chromatic sequence using triad over bass chords

B/C--------------C/B----------Db+/Bb--------D/Eb------------Eb/Ab-----------C/Db----------C#/B
C-D#-F#-B-----B-E-G-C-----Bb-F-A-Db-----Eb-F#-A-D-----Ab-G-Bb-Eb-----Db-G-C-E-----B-G#-C#-E#

Fear no interval.

[JonnyPac]

Those make sense, of course. I'd actually drop the C on top though.

[BigDaddyLoveHandles]

I think Monk liked the major 7th chord with the 7th under the root, but that's Monk.

[JonR]

Originally Posted by BigDaddyLoveHandles

I think Monk liked the major 7th chord with the 7th under the root, but that's Monk.

I was going to mention Monk. He did like those minor 2nds, anywhere he could get them. As I mentioned, it's a pretty common maj7 piano voicing - now - to put the maj7 right next to the root (in the right hand anyway): eg 5-7-1-3.

Not sure whether even Monk would have liked the maj7 a b9 below the root though...

[JakeAcci]

Originally Posted by JonR

I was going to mention Monk. He did like those minor 2nds, anywhere he could get them. As I mentioned, it's a pretty common maj7 piano voicing - now - to put the maj7 right next to the root (in the right hand anyway): eg 5-7-1-3.

Not sure whether even Monk would have liked the maj7 a b9 below the root though...

not maj7, but:
"Played Twice" bar 9 - melody note is Bb, harmony is considered F7, piano voicing on the and of 3 is, from bottom to top: F A Eb Bb - the Bb does not resolve to A or C

On guitar, when playing with a bassist, I use this voicing for that chord, from low to high, on strings 4321: A Eb G Bb

I haven't investigated more thoroughly, but I'd imagine with a little prodding one would find many examples of Monk using the b9 interval in voicings of all sorts of chords.

[JonnyPac]

Monk, Andrew Hill, and Cecil Taylor are some classic users of dissonant intervals- They are all a lot of fun to listen to.

[danjw]

I agree totally that the teaching of so called avoid notes is counter productive. It's the creative use of dissonant intervals that gives jazz its colour and helps define a players "voice".
Also CST gives an unrealistic framework when it comes to "conssonant" intervals over chord changes.
Take a iii vi in C:
|Em7|Am7|
CST tells us that the most consonant scale choices would be Dorian for both, as it contains no avoid notes. In reality the change of key that would occur with parallel dorian scales creates its own dissonance. Or to put it another way "has an unsettling effect on the key center".
In the context of a larger progression in Cmaj, Emphasizing b9 and b6 on the Em and b6 on the Am is actually more consonant because of the overall key.
In short consonance and dissonance are dependant on the underlying harmony and also the function of that harmony at any given time I.E (as someone else pointed out) what comes before and after.

[JonnyPac]

Avoid notes are kinda BS, but there is a hierarchy among tones. From my blog:

It is a common pitfall for students of chord-scale equivalency theories to give every note within a chord-scale equal treatment. There is a tonal hierarchy that must be recognized. The core triad needs to be thought of as the lower structure, the seventh as what I call the “gateway” tone, and the other chord-tones as “upper-structures” or “extensions”. Every note besides the core triad may be treated as a “tendency tone” (meaning a tone that is unstable and naturally tends to resolve either upward or downward to a more stable tone) depending on the immediate context. “Avoid” notes or “handle with care" notes are the most unstable tones within each chord-scale. Tonal hierarchies within each chord-scale can fluctuate depending on the harmonic conditions of the music at hand. Use your ear to determine the level of complexity that is appropriate.

[whatswisdom]

Originally Posted by danjw

Take a iii vi in C:|Em7|Am7|...CST tells us that the most consonant scale choices would be Dorian for both, as it contains no avoid notes. In reality the change of key that would occur with parallel dorian scales creates its own dissonance.

I would have thought Phrygian & Aeolian were the most consonant, or am I missing something?...