I've been spending some time with this question, and its paying some fruit. I mean we spend a lot of time thinking about consonance, but dissonance control is a VERY interesting topic to me at present.

I have been thinking about ways of classifying dissonance and how this can be used as a creative tool, a simple example being sound a Db major 7 (in the key of C) then swiftly grabbing a C major root. Another example would be the second note of Bernstein's 'Maria' - sharp 4. This seems to me to be a different type of animal a 'melodic dissonance' if you like.

When people talk of 'introducing spice', it always leave me dissatisfied, because I would like to understand the hierarchies that control the dissonance and produce all those lovely labyrinths of sound and use these controls myself - methodically.

Anyone care to chip in?



Z

Hi,

To understand how dissonance works, a study of two-part counterpoint would be very helpful.

Gradus ad Parnassum by Johann Fux (just to clarify, 'Fux' rhymes with 'books') is pretty much where it all began.

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

I read a translation of his treatise a few years ago and it gave me a great deal to ponder.

One of my favorite books is C.H. Kitson's Counterpoint for Beginners. Kitson presents his theory very clearly and his book is straightforward to read. It's also very concise.

Counterpoint for Beginners

The thing with counterpoint (or contrapuntal harmony) is that it is how music was created before the notion of vertical chords came to be understood. The only tools that composers had to work with were 'melodic patterns', 'consonance' and 'dissonance'. J.S. Bach followed the principles of counterpoint with his compositions.

As counterpoint grew through 2-, 3- and 4-part creations, musicians eventually came to see a consistency in vertical alignments of notes - with time, these consistencies came to be recognised as the chords we understand today.

Understanding the mechanics of dissonance and consonance is fundamental to contrapuntal compositions. My experience is that the knowledge is also fundamental to understanding how chords work at their most conceptual level.

I suggest you get hold of Kitson's book. It was published in 1927 by Oxford University Press.

Regards,
Noel

Hi Noel, I have read Fux and others. Fux was writing before the emergence of equal temperament when modes were Ecclesiastical, before the major scale was a universal. I found it difficult and ultimately unconvincing - 'devil in musica' and all that.

The Romantics brought this on a notch, then Debussy, Jazz, Schoenberg and, I am sure you know....the twelve tones always available as a palette...

I guess I should have said something like 'codify dissonance pianistically', because that's what I am working on.

Bi-tonality using the circle of fifths relationship between keys is as good a starting point as any for controlling the level of dissonance I would have thought. Combining triads from keys that are distantly related in the circle will obviously give higher levels of dissonance than those lying closer together. This approach stresses superimposition rather than substitution and is a good way of retaining a connection to the original harmony of a tune if you're reharmonizing.

The other tools you might employ if you're thinking harmonically of non-triadic structures is Paul Hindemith's notion of interval tonics and degree of dissonance of each interval type.

So Maj 2nds, Maj3rds 5ths, maj6ths and maj7ths all have lower note tonics. minor 2nds m3rds 4ths m6ths and m7ths all have upper note tonics. the b5th being ambiguous in this regard.

Using the distance between interval tonics as a guide, you can easily see that chord or line formed by maj3rds built on C and D is less dissonant than one yielded by maj3rds on C and Eb, which in turn is less dissonant than maj3rds starting on C and F# for example.

Things obviously become more complex when you factor in the inherent dissonance level of the intervals you employ. But even here you can see that a chord made up of Major 7ths on C and F is less dissonant than one with Maj7ths on C and Eb.

Hindemith's classification of chords in terms of dissonance level is based on their intervallic makeup with the most dissonant being structures containing the highest number of adjacent minor seconds, more than one flatted fifth and whether or not the resultant chord suggest a tonic.
A useful comparison is Ernst Krenek's classification which i must confess i didn't know of until I read :

consonance and dissonance

Hope this is nearer to what you had in mind.

Alan

Today I was playing Over the Rainbow - as a jazz ballad. Running up the chord to a big Eb t the end both my hands are over middle C and ready to play triads an octave apart.
Standard stuff and of course it will do, but...

I wanted to put a bit of uncertainty into it, just a question begged at the end, nothing too drastic. I tried various options and then settled on replacing the third in the left with a ninth. For me ninths and sixth are closely sonorous and can easily be exchanged. This note creates a little damage to the integrity of the major end, but just that little I was seeking.
I can feel that ninths and sixths are diatonic and although not stated in the chord are pretty straightforward alternatives. Ninths, sixths, then what? I don't have a hierarchy for selection, concord to discord.

For me the major seventh sticks out big time, its the leading tone begging for the octave a very strong pull, not at all like its sister the dominant 7th. Using s major 7th to replace dominant 7th or vica versa. This again is a question of classifying dissonance, most text point out that the dominant seventh has a triton built from third to 7th - fair point, but to my ears a major seventh seems more dissonant. Why is this so?

Some books that you might like that address this topic are:

"This is Your Brain On Music" Daniel Levitin
"A Natural History of the Senses" Diane Ackerman

At least I believe I remember reading on consonance/dissonance in those books and they come from a non-musician's viewpoint as to why the brain of MOST people tends to like consonance and defines it, for the most part, similarly across cultures. The microtonal music of the east is an exception.

I see the Major 7th to Octave leading tone progression you describe (for example C,B to C, C) as implicit in a V to I cadence of G7 to C. It's what is known as a suspended cadence where the V has a 3rd (B) and a 4th (C) which anticipates the tonic C. The absence of a b7th (F) just means that there is no voice leading to the Major third of the C tonic (E) should you wish to include it in the cadence.

Similarly if I played the b7th (C,Bb) I feel it does have a strongly implied resolution, this time a semi-tone downwards to the Major 6th C,A. Again it's an implied V to I cadence partially stated. This time the cadence is C7 to F major with A functioning as the third of F which is the tone omitted on this occasion but as in the above example, strongly implied nonetheless.

As for an order of dissonance on the tonic I would say the next tone you might try is the b5th preceded by a bII dominant. After that you could try the Maj7#5. Next up in the dissonance food chain would be a b3 against the 3rd giving you the Maj7#9 chord. I would be careful with a b9th; it's best voiced as 1, maj3rd, maj7, b9, 5 but still not to your liking even when using a bII alt7 as the dominant to lead in.
The 4th doesn't sound resolved enough in a third based context, the b7th on the tonic sounds okay in a blues progression but not on a standard maybe!

Bear in mind that truly dissonant sounding chords wouldn't so much substitute one tone for another but play both together (i,e b7 against maj7, b3 against maj 3rd)and with more than one semi-tone clash present simultaneously). Including colour tones, extensions or changing the chord quality is not necessarily by itself dissonant sounding. There has to be a feeling of 'disagreement' or contradiction in the voicing to some degree where the implied function and tonality is obscured.

Alan

I am a student of the ideas associated with improv and jazz improv.

This is also called tension and release. In jazz you get disonance from the chords that are in play and your use of the notes that bring about the dissonance. Flat 9, Sharp 9, Flat 5 sharp 5. I'm learning about this stuff from a guy that lives in my computer and comes out whenever I want, it's like having your favorite uncle come over and show you amazing stuff for next to noting.99centguitarlessons.com, See my post in Woodshedding for too many details.

There are other ways: take two or three notes from one of your favorite licks and play them up or down a half step as part of your like. You can simply state your lick and restate it a half step higher or lower. It should not be a very long lick people will think your lost.

As you delve into the whys and how's of jazz or just spicing up country blues licks {many class on this @99cent...] you will come across the idea of displacing a scale from it's home root. These things were a revelation to me. There is a class called Major Scale Usage @99cent. it is based in blues and pentatonics. Extra easy to learn and will change how you sound in a blues setting in an hour or so. The class is not that long but you might need to woodshed the idea a little. Check our John Scofield's On Improvisation video or DVD. There is a whole section of displaced major minor and dominant pentatonics. i.e. for altered chord X begin a minor pentatonic from the flat six of the chord. That's just a for instance I don't know the exact chord he used. BIAB is made for stuff like this. There is much more to this endless learning curve, that's what keeps you practicing. If you are not evolving you're are in some sort of stasis. What comes next is not good.

Ron

Dissonance is in the ear of the beholder. With education and familiarity, what one originally thought was dissonant may become less so, or even desirably consonant, over time and perhaps with practice. Originally an improvisor by ear, once I learned more music theory as a teenager, a lot of the mystery cleared up and I suddenly heard beauty in what had been dissonance based on confusion.

I tried a quarter-tone trumpet last year, and that was pretty hard to get my head around, but I think if I owned and practiced one, I might make a go of it.

Zero, one of my favorite chord examples along the lines of your maj7 is the #9 chord, with a major third in the lower octave and a flat nine minor third on top. Chords like this are so wonderful for a jazz improvisor because they can be taken almost anywhere. What comes next can be very good (yes, I know what you meant Ron!).

thank you Matt exploring...

Re-reading this, I meant to write minor third on top. That is enharmonically the sharp nine. Sorry, Zero. Post has been edited.

[The major third in the lower octave and the minor third in the upper octave creates another interval of a major seventh, with the accompanying tension.]

Just been watching the video for Cubase 8 Pro's new feature "Chord Pads". I think a graphic they are using gets somewhere near where I am trying to get to with 'classifying dissonance'

I recommend checking out the video on their site. They have a animated graphic in Cubase which lets you select a root, it then shows you the 'proximity' of various chords in onion skin form - four in the first circle, 37 chords in all, for each note. They talk about 'adaptive voicing'.

If I had a mind map something like this...

Z

IMHO, there are two uses for dissonance:
1) to retain the listener's attention
2) to prove a philosophical point

the first point is evident in a lot of Beatles chord progressions where they borrow chords from other keys to mix things up.

the second point is mostly used by jazz and classical composers where they use dissonance to move to another segment of the song, or to move the original idea to a darker or even lighter aspect, etc

my favourite usage of dissonance is the ambiguity we hear in "the girl from ipanema". It's hard to solo to that chord progression unless you totally let go and just imagine yourself at the beach or something since there's not a lot to hold on to because of the changes in key.

The tension and resolution of the 7th vs. maj7th come from different places.

The physical explanation of tension can be often be explained by looking at the overtone series. Tones and invervals at the lower end of the series tend to be heard as less dissonant, while those at the upper end (excluding octave doublings) tend to be more dissonance.

I say "tend to" because musical context has a large part in how we interpret tension.

The first 8 overtones for C are C, C, G, C, E, G, Bb, C.

From that perspective, the Bb should actually be a member of the C major scale. So it's not surprising that it's fairly consonant. The decision of which way to lean the 7th of the scale - to the B or Bb has been a matter of debate over time.

Additionally, the Bb in the C7 chord signals that it doesn't belong to the key of C major. The most closely related major scale it does belong to is the key of F major, which is why the Bb helps the C7 nicely resolves to the F.

One can also propose a set of consonant intervals based on the overtone series: octave, fifth/fourth, third/sixth, seventh/second. From that perspective, the interval from the root to the flatted seventh ranks fairly high on the dissonance chart.

In contrast, the B in the Cmaj7 doesn't quite have the same physical justification. There are logical reasons why you might want to fill the gap between the 6th and 8th tones of the scale, but they aren't strongly supported by the physics of the overtone series.

The interval of a minor second also ranks higher than a major second as a tension.

Finally, the maj7 doesn't create the same sort of harmonic implications as the dominant 7th chord. Sure, it's a 7th tension (of sorts), but it doesn't create the same kind of V->I movement that dominant 7th creates.

So there is plenty of justification to saying the maj7 chord is more dissonant than the dominant 7th.

I hear what you're saying but as a chord member the presence of a minor second/major 7 has to be weighed against the other intervals that make up the chord. When viewed in isolation a minor second or major 7th is of course more dissonant than a major second.

However in the context of Cmaj7, the effect of two major thirds a minor third and a perfect fifth between the major third third and the major seventh when voiced as 1, maj3, 5, maj7 effectively dilute the minor 2nd and make the chord as an entity sound like the resolution it most often is.

If it were otherwise the tension would require resolution to another chord and as you rightly point out it doesn't have that pull towards a tonic as it is the tonic in itself. Even if we have the minor second as the uppermost interval 1, 3 5, 7, 1 it still doesn't negate the the effect of the other voices.

Similarly when considering the dominant 7th as a chord remember also that as well as a major second it contains the all important b5th which gives it it's restless character, demanding a stepwise resolution to the third and the root of the tonic chord. It also contains successive minor thirds built on the major 3rd forming a diminished triad.

Alan

Dissonance is a very important part of music, without out it, music would get pretty bland. Just like you need black/white, day/night, good/evil.. You need the yin/yang to make something complete.. a dissonant note at the top of a chord, can be very beautiful..

I have discovered, when working with scales,, putting dissonant notes on the and of the beat, sometimes, giving them a shorter duration, and softer velocity, will let you get away with a lot.

Remember you jump over the dissonant notes, and rest a little longer on the consonant notes. .

Off course you could change this to make a certain musical point.. yes, dissonance is every bit as important as consonance in notes.


Mark Styles

Unpacking this a little. For my ears, Consonance can fall on any beat, but dissonance leans towards the off beats. Obviously rules can be broken.
I was wondering about the classification and function of dissonance. Beyond the chord tones , as they stand in a modal position, it seems to me that the other tones sound dissonant according to their function - the Phrygian chord III, for example implies a flat 9th, a tone belonging to the key, as I think Ray pointed out, beyonf this relationship what about the other tones? Do they have a hierarchy?


I confess I am not really sure of the question, if I was then the answer would be implied


Z

Right on, I experienced this and a whole lot of stuff became prettier and more accessible. History has proved that, too. The more we hear something "new", the more we tend to "accept" it over time. I think it works that way with time signatures, too.

Dissonance is only partly in the ear of the beholder - sort of.

A perfect fifth can't sound dissonant, it's always going to be pure - look at an oscilloscope to see why.

All the notes have a defined physical character. However, we can gradually become aurally acclimatised to a dissonant interval - psychologically and it can therefore become more familiar and less of a surprise. It sticks out from the terrain in the same spiky way, but we are accustomed to the feel of it, it becomes less of a contentious issue for the ear. It does not become less dissonant though- physically the wave form is the same and interacts with the other waves according to physical laws.

Western ears have gradually accepted a larger pallet since Debussy ish.

To me, dissonance is a musical and subjective term, and it is in the ear of the beholder, rather than being explainable based on harmonics etc. I would define dissonance as a voicing of notes that sound unpleasant to the listener.

It depends on the style being played, as well as the people listening to it. For example, the flat 5 in desafinado (slightly out of tune) was humorously referred to as "out of Tune" in the title likely because many people would hear it as dissonant. Yes that same flat 5 is heard everywhere and prominently, including pop tunes, and it is not heard as dissonant or "out of tune".

There are some intervals that can make a nice chord sound dissonant though. An example is a CMaj7 voiced from low to high as B,E,G,C. The B to C creates a flat 9 interval, and it sounds really bad. Change that C to a D and it sounds sweet again - even though we have introduced a "ninth" which some people would consider dissonant because it is a non chord tone.

This discussion far exceeds my music technical knowledge. But Peter's remark causes me to think back (waaay back) when I studied and worked in psychology. If for some reason we had evolved to be hardwired to dislike dissonance (think bitter taste) then we would certainly "know" what dissonance is and we would all quickly agree upon it -- at least from a phenomenological perspective. But as Peter noted it is ultimately in the ear of the beholder. And in that case there are many variables that can play into why it sounds unpleasant...mostly related to our experiences, i.e., learning.

Pardon the ramble but it is a fascinating subject.

A big ole FWIW!

Bud

I have thunken my Thinkin.....

The above is true, but you can't even begin to classify what is and what is not dissonant without referral to the frequency and timbre of the note (in and out of aural context).

I think there is a semantic thing going on here, some use the term like a finger in a cake shop, subjectively. It is like the word "like", a personal preference.

When I describe a note that is dissonant I note that is rarely a perfect fifth. Sketching in the notes in perfect fifth cycles gives more and more dissonance, by a symmetrical pattern: Root 5 9 6 3 7 #4 b9 b6 b9 #9 b7 4 1 . (The chromatic scale)

I am thinking this might be a way to classify dissonance?... possibly it does quite well, but the perfecft fourth seems logically out of place.

... etc

interesting thread


Z

As far as Desfinado goes, I think modally. If its a relative minor then the note fits in glove like, if its a major chord then there is dissonance. No note is dissonant or consonant in its own right, only in a (physical harmonic) context can this be measured.

So in relative minor, Phrygian, locrian its consonant with the key.

I guess that narrows the field a bit.. if seen from that perspective