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Why is it important to know the function of a chord
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PostPosted: Tue Mar 01, 2005 4:30 pm    Post subject: Why is it important to know the function of a chord Reply with quote

There is something i don't fully understand, I thought that maybe some of you might shed some light on this matter. We frequently see people say that in order to improvise over altered dominant chords such as B7alt we just need to look at the jazz minor scale up a half-step. For B7alt takes C jazz minor scale.

While it is easier to think of a B altered scale as a C jazz minor scale starting on B, eventually we need to understand the notes relative to a B major scale, rather than a C minor scale. For example: the major third of a B7 chord is a D#, the minor third of a C minor scale is Eb. Although it's the same note, it is a different scale degree, plus it is a different enharmonic spelling. It doesn't make sense to play an Eb on a B7 chord. This just leads to confusion.

Further, a B7 chord has an entirely different harmonic function than a Cm chord, and the scale we use should help us understand where the chord is going. Thinking of the C jazz minor scale while playing on a B altered chord will provide us with the correct pool of notes, but will not help us to understand the function of the chord.

My question is this, how should we approach a new piece for which we want to improvise over ? How do we analyse the different harmonic functions of this new piece ? If i know which scale to use over a set of chords or a particular chord, why should i be concerned by the function of a chord ?

I - tonic. II - supertonic. III - mediant. IV - subdominant. V - dominant. VI - submediant. VII - leading tone.

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PostPosted: Tue Mar 01, 2005 7:08 pm    Post subject: Reply with quote

My bet is that ... each song can be broken down into 'phrases,' which are sort of like musical 'sentences.' If a song is like an essay, verses would be paragraphs, phrases would be sentances, figures would be words (figure = a bunch of notes together and notes would be letters. When constructing each of your phrases in an improvisation (solo-wise) you don't want to sound too monotenous so you will try to punctuate your solo.

When you write, you make a sound in the reader’s head. It can be a dull mumble--that’s why so much government prose makes you sleepy--or it can be a joyful noise, a sly whisper, a throb of passion.

Listen to a voice trembling in a haunted room:
"And the silken, sad, uncertain rustling of each purple curtain thrilled me—filled me with fantastic terrors never felt before..."

That’s Edgar Allan Poe, a master. Few of us can make paper speak as vividly as Poe could, but even beginners will write better once they start listening to the sound their writing makes.

"My tools of the trade should be yours, too. Good use of punctuation can help you build a more solid, more readable sentence."

One of the most important tools for making paper speak in your own voice is punctuation.

When speaking aloud, you punctuate constantly--with body language. Your listener hears commas, dashes, question marks, exclamation points, quotation marks as you shout, whisper, pause, wave your arms, roll your eyes, wrinkle your brow.

This is what you want to achieve when you improvise, you want to punctuate your musical sentences in order to convey your feeling to the listeners. To do this you must look at the function of those chords you want to improvise over because they tell you where you should place your punctuation marks in your solo. This is the way i see it, i just can't find any other use for the function of a chord when i improvise. I must confess that i still find this subject (function of a chord) an ambiguous or an enigmatic domain. It's not always clear when a chord play a sub-dominant role. Take for exemple the third (iii) chord of the diatonic C major scale : Em, It is not always clear that it's a the third chord of this scale, it might be the ii or the vi of this scale if the key center is not clear or it might come from a minor scale.

It's a good question though. I hope you will find an appropriate answer from other members of this forum.

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Sal Chichon

PostPosted: Tue Mar 01, 2005 8:27 pm    Post subject: Functional Harmony Reply with quote


I think knowing the function of a chord is important because understanding a song`s cadences allows to foresee tensions and resolutions (tonic >>> subdominant>>> dominant >>> tonic). I think it facilitates substitutions and melodic ideas....

BTW that`s how I understand the importance of knowing chord function, but I may place too much emphasis on it. Also, I`m not a strong improviser, I`m just offering my 2 cents!!!

Check out this website for more info on phrases and cadences (in the lessons menu...)

I`d like to hear what you have to say, Cheers,

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Posts: 114
Location: Los Angeles, CA

PostPosted: Wed Mar 02, 2005 12:06 am    Post subject: Chord function Reply with quote

In simple terms...

Knowing what scales you can use over certain chords is literally just vocabulary you can use. If you know that you can play a C melodic minor scale over a b7 altered chord, this gives you information you can work into your improvisations. If you like the sound and flavor of this scale when played over that chord, then you can further experiment with it, knowing that the notes work and give a certain flavor. Once you know this then you have a springboard, a place to draw notes to improvise with.

My feeling is that jazz is all about the "sounds". Theory is nothing more than a means to an end - a way to get to the good notes. Learning what scales you can play over certain chord progressions fuels this.

Joe Pass once said "Don't ask me about modes, I don't know anything about that". But he had all the good notes didn't he? My advice would be to try not to get too heady about this, you simply have to learn to "hear" strong sounds over chord progressions.

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PostPosted: Wed Mar 02, 2005 3:15 pm    Post subject: Reply with quote

Chris you said:
... you simply have to learn to "hear" strong sounds over chord progressions.

Easy to say but ...
What defines a strong line?

You might say ...
A line that spells out the chord changes.

Ok for me but ...

How are chord changes spelled out by melodic lines?
Using the system of Tension and Release analysis the obvious became clear.

By synchronizing the strong beats of the bar with the strong tones of a chord scale.

The Release beats of a bar ("one" & "three" and the "on" beats of every quarter note) are the strong beats for the bar. The Tension beats of the bar ( "two" & "four" and the "ands" of each quarter note) are the weak beats of the bar.

The Release tones of a chord scale are the root, third, fifth & seventh. They are the strong tones of the chord scale.The non-chord tones are the weak tones.

Gee ! answer and reply in the same post.
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PostPosted: Wed Mar 02, 2005 3:31 pm    Post subject: Reply with quote

I have a question for Chris:

Your course contains many ex. of licks over a ii-V-I cadence. Sometimes i have the impression that one must memorize al these many licks (in all twelve keys) and then somehow string them together to get something that sounds good. Is it the purpose of these many licks ?

Or have you hidden some mysterious plot device that I have not unravelled yet ?
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PostPosted: Wed Mar 02, 2005 6:57 pm    Post subject: Reply with quote

I think some really good stuff has been said here - here's my 2p's worth.

In order to understand harmony, we can build different mental models. These have different terms, and different ideas and logic, but when it comes down to it, all must mirror the same artistic principles: why for example, a G7 chord likes to be followed with a C chord, and why an Am chord sounds sadder than C major. That's all subjective stuff. No one really knows why minor sounds the way it does, or why the common harmonic cliches (such as II-V-I) have come into such prevelance over the last three centuries. Is is human psychology, or nature?

Hugo Reimann, working in the late nineteenth cetnruy, came up with the idea of there being essentially three functions a chord could have in any key - somewhat confusingly named tonic, subdominant and dominant. The II-V-I favoured as a cadential formula by musicians from about 1610 onward, has one of each - II is subdominant and V is dominant, and I is tonic. The bass also moves in fourths (ascending), which gives a pleasing strengt to the progression in root position - as it has been used by Monteverdi and Charlie Parker.

Arnold Schoenberg in his Theory of Harmony used a different approach.

The Lydian chromatic system of George Russell models everything based on a stack of fifths - the lydian chromatic scale. It's an impressive system, an merits a look, even though it can seem dense at first.

My idea is simpler - music has two regions - inside and outside. How inside or outside a given set of notes is can be worked out quite mathematically. The domiannt chords or secondary domiannts are simply musical 'arrows' indicating 'tonic' regions within the outside wilderness. I find this helps me understand both conventional harmony, and come up with compositions and new improvisational ideas in any style.

They're all just models. Simply use the one that makes the most sense to you, or if none of them appeal, make up your own (thats what I've done)
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Location: Los Angeles, CA

PostPosted: Wed Mar 02, 2005 8:37 pm    Post subject: 2 5 1 examples in PWYH Reply with quote

The 2 5 1 examples are for two reasons.

First, because yes you simply do need to build a vast vocabulary and you can use any examples in complete.

Second, and more importantly, you need to build a vocabulary of "connections" when playing bebop/changes. Sometimes the changes go by so fast you cannot opt for a scale like melodic phrase across all three chords, you need to incorporate chord tones with added embellishments (ie: b9 or b5 on chord V) to really say something. The 2 5 1 examples show you how you can use these connections. By studying the movement (and listening to the audio examples) you can get used to seeing where the notes come from and how you approach the changes. Then you will no doubt retain the phrases that feel natural to you or tweak your ear.

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PostPosted: Wed Mar 02, 2005 8:55 pm    Post subject: Reply with quote

May I add my 2 cents to what Chris said in saying that what is important is to copy only those ideas that strike you on an emotional, gut level. Make them into exercises and learn them in all twelve keys. Once you've learned them, try to alter them to fit over other sets of changes. Redorder the components in the idea to find different ways to put them together. By exploring that idea in as many ways as possible you are exploring your own way of hearing and playing.

Deciding what to practice is always a challenge. When it comes to practicing use one rule and one rule only: Practice only what you like! I don't mean that once you learned a lick that you play it over and over again. I mean copy only the ideas you relate to strongly on an emotional level. Let your feelings be the guide. Trust them.
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PostPosted: Wed Mar 02, 2005 8:59 pm    Post subject: Reply with quote

To use our intuition and our emotions to select those musical ideas we wish to copy is just plain common sense. But the question remains: how much copying do we need to do and what to do with the ideas we‘ve copied ?
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PostPosted: Wed Mar 02, 2005 9:04 pm    Post subject: Reply with quote

The point being that you don't need to collect massive amounts of licks, you need to collect a small amount of the right kind of information and learn how to get the most out of it.

Contrary to popular thought, you don't want to memorize a bunch of licks and then try to play them as a solo. That's not improvisation, that's craftsmanship. You'll discover that although you might be making some nice sounds by playing rote ideas , you will be, guaranteed, bored to tears and so will your listeners. You don't want to play what you practiced. That's not what practicing is for. Both you and your audience want the adventure of making stuff up as you go along, playing ideas you never practiced. That's why it's called improvisation.
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PostPosted: Wed Mar 02, 2005 9:13 pm    Post subject: Reply with quote

But how then can we do this ? If i get used to take a route to go to some place then how can we expect to find another route to go at the same place ? When I practice a lick it's the same as taking a route. My fingers follow the same steps along this route (read lick) over and over. Can we expect they will find another route in front of an audience ?
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PostPosted: Fri Mar 18, 2005 11:36 pm    Post subject: Reply with quote

Here's another reason for you ... Cool

The Number System

To simplify the process of playing any song in any key, the pros use a number system. This system refers to the ROMAN NUMERALS which represent the functions of the various chords used. You might want to review the chapters on chord construction, and the use of the major scale in improvisation before going any further.

To quickly recap that info:

1. Chords in any given key center are based on scale tones.
2. By numbering scale tones we create chords built with thirds.
3. For each scale tone there is an appropriate chord, according to the key.
4. Chords have different functions which create a sense of tension and release.
5. Those functions are consistent among all keys, so the same relationships exist between chords and melodys when the key is changed.

Here is the scenario. A vocalist is sitting in with your group. She wants to sing a song you know, but has asked for it in an unfamiliar key. Let’s say for example that you would normally play this song in the key of Cmajor. The singer wants it in F major. The novice player will pray for an opportunity to write it all out, but these situations come up pretty fast and there isn’t always time to do a transcription. The pros have a trick that makes it easier.

First, look at the key of C major. The 7 chords for this key, which correspond to the major scale tones are:

I - Cmaj7
II - Dm7
III - Em7
IV - Fmaj7
V - G7
VI - Am7
VII - Bm7(b5)

Now look at the chord progression for Example #1:

Here is the same progression with a numbers approach:

The Roman numerals indicate the functions of the chords.

Now look at the new key F major.

I - Fmaj7
II - Gm7
III - Am7
IV - Bbmaj7
V - C7
VI - Dm7
VII - Em7(b5)

Here’s the same progression (I-VI-II-V) in the new key.

Apply the same concept to every key. By learning the functions of the chords, and developing a different point of view about learning a song, you can quickly change keys on the fly with many pieces of music.

Some things to keep in mind:

1. When you learn a song, plan on playing it in several keys, and apply the numbers approach to your perception of the song itself. Don’t see the song as individual chords, but rather see how each chord functions. Think of it like a language. When you learn a language, you begin with a few simple words. Eventually your vocabulary increases and you begin to talk in sentences, which grow to paragraphs, pages, and volumes. Music is exactly like that. You start with notes, then grow to chords. Now you are at that stage where you are begining to form “sentences” or chord progressions. As your “vocabulary” of phrases increases, so does your ability to “speak” clearly in the language of music.

2. The process I’ve outlined here becomes more complex when key changes occur within the actual chord progression, that are not indicated in the key signature. Start with songs that stay in one key. After awhile, you will begin to see more complex progressions. For example, you may recognize one variation as a II -V - I pattern in a different key. This will help you to remember the sections of songs which do not remain in one key.

Sometimes when we are on stage and someone doesn't know the song, we use this system to call the chord changes on the fly. The cat who doesn't know the song can follow along without too much difficulty. I was recently on a gig and the singer (Elizabeth Messina) wanted to do a tune and no one in the rhythm section knew it. As she sang the song, she showed us the numbers behind her back. We followed her through the tune with ease, and she never missed a lyric. Instant arranging, and a tribute to Elizabeth's musicality. It is rare to find singers this hip, but when you do there is no end to the fun you can have.

Original article was posted on, he is a well known jazz guitarist in the Louisiana area.
Special thanks to Dean Fransen for his input on this article.
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alex hunter

PostPosted: Sun Mar 20, 2005 7:28 pm    Post subject: Reply with quote

Use many different methods of figuring out the function of a chord progression. They will all compliment and reinforce each other.
One Method I tend to use is picking one small passage from a standard and getting inside it and figuring what its all about. A research project you could say.
I studied the progression E-7 Ebdim7 D-7 G7 Cmaj7 from "my romance" and played lines that seemed to fit in a very stream of conciousness kinda way. At the same time i figured out the scale patterns and functions to see were the chords were going and why. Basicaly i both simplified and complicated matters which realy helps me cos i learn in quite an unorthodox way. But it just so happens i realised that this progression occurs in quite a few standards (all the things you are etc) and my lines sound natural over them.
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PostPosted: Wed Mar 23, 2005 6:49 pm    Post subject: Reply with quote

When i looked the first time to your cadence:
E-7 Ebdim7 D-7 G7 Cmaj7 from "my romance"

I was intrigued because at first sight it was not evident what was the function of the Ebdim7 chord. But after examination i realised that Ebdim7has the following notes :

Eb-Gb-B-D and B7 has the following notes :

Both chords share three notes : Eb-Gb-B

This means that Ebdim7 substitutes B7 or plays the function of this dominant chord.

Looking at the cycle of fourth we have the following cadence B - E. This means that E-7 plays the role of the first chord, we should treat this progression as a V-i. Following the cadence E-7 Ebdim7 we have D-7 G7 Cmaj7, this is a typical ii-V-I.

Maybe i am wrong but it's my understanding according to my theory background.
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