|
Please note this is an archived topic, so it is locked and unable to be replied to. You may, however, start a new topic and refer to this topic with a link.
KI4PRK - Posted - 05/13/2009: 07:31:55
I've been looking into this lately. I know one basic substitution that I use rarely, the tritonal substitution. But I've been looking into these more, and I assume they are very useful in jazz. I enjoy theory as well, so don't hesitate for a full explanation  !
Thanks,
73, Brennen
Mick S - Posted - 05/13/2009: 09:28:54
The Mel Bay Book - Joe Pass Guitar Chords - written by Joe Pass, has a section in the back - maybe a dozen pages, that explains substitutions very clearly and builds on itself very logically. He gives examples over the most common progressions - Blues , vi-ii-V-I, etc. There's not very much explanation, but the way it's laid out is so clear that it's almost unnecessary. The guitar chords section won't necessarily help you, but the chord progression section is very good. The book's only like $6 or something.
pearcemusic - Posted - 05/13/2009: 09:44:24
from outsideshore.com
http://www.outsideshore.com/primer/...eharmonizing
Reharmonizing
An accompanist may occasionally reharmonize a chord progression to sustain interest, introduce contrast, or create tension. This involves replacing some of the written or expected chords with other unexpected chords. Substitutions such as the tritone substitution are one type of reharmonization.
Some musicians spend a lot of time trying different reharmonizations when working on a tune. However, unless they tell the soloist what they doing beforehand, many of the reharmonizations they may come up with are not suitable for use in accompanying, since the soloist will be playing from a different set of changes. There are some simple reharmonizations that can be used without disturbing the soloist too much. The tritone substitution is one example; at any time a dominant seventh chord is called for, the accompanist may substitute the dominant seventh chord a tritone away. This creates exactly the same type of tension that is created when the soloist performs the substitution. Another simple reharmonization is to change the chord quality. That is, play a D7alt in place of a Dm, and so forth.
Another common reharmonization is to replace a dominant chord with a ii-V progression. This was already demonstrated when discussing the blues progression; one of the progressions replaced the F7 chord in bar 4 with a Cm7 - F7. This is especially common at the end of a phrase, leading to the tonic at the start of the next phrase. Most of the scale choices the soloist may have been using over the F7 chord will also work over the Cm7 chord, so this reharmonization doesn't usually create too much tension. This technique can be combined with the tritone substitution to create a more complex reharmonization. Rather than replace the V with a ii-V, first replace the V with its tritone substitution, and then replace that with a ii-V. For example, in bar 4 of the F blues, first replace the F7 with B7, and then replace that with F#m7 - B7.
Another type of reharmonization involves the use of alternation. Rather than play several measures of a given chord, the accompanist may alternate between it and the chord a half step above or below, or a dominant chord a fifth below. For instance, on a G7 chord, you might alternate between G7 and Ab7, or between G7 and F#7, or between G7 and D7. This is especially common in rock based styles, where the alternation is performed in rhythm. If the alternation is performed regularly, such as throughout an entire chorus, or even the whole tune, the soloist should be able to pick up on it and control the amount of tension produced by playing along with the reharmonization or by playing against it. That is, the soloist can lessen the tension by changing scales as you change chords, or increase tension by keeping to the original scale.
The Pearce Family Bluegrass Band
www.pearcemusic.com
RPM - Posted - 05/13/2009: 11:07:20
There’s a lot to chord substitution, especially in jazz, as you can see. It can get pretty deep.
A possibly simpler other way use chord substitutions is in the relationship of the melody to the chord.
Basically, some chords that contain the melody note other than the “basic” chords of the song can be substituted.
Of course, that doesn’t mean any chord at all with the same note, but you can play with it to see if it makes sense for what the melody is doing.
For example, say you’re in the key of G and switch to the C chord on an E melody note. If you go to an E major chord instead, it’s going to be a harsh change and probably not lead well into the rest of the song’s changes.
But you might go to an A minor chord instead of a C if the melody is on an E. Am is also in the key of G and is also a minor dominant chord of a D chord. (Am is the v of D.)
So if the chord after the basic C is a D, an Am instead of the C might be a nice smooth subsitute to get to the D.
Or you could go out of the key and subsitute an A7, (also has an E note) which is the V7 of D. If you opted for that -- a common bluegrass substitution -- it would sound like you were modulating to the key of D.
A band I was in played a version of Tennesee Waltz in G where we substituted a Bm7 for the D chord in the chorus (both have F# notes) and with a B7 (also has an F#) the last time through. It was added some nice color.
Also, the melody dosn't have to match all the way through the change, of course, especially if the subsituted chord has enough notes in common with the "basic" chord. Bm, for example has two of three notes in common with a D chord.
(But if you're in G major and the D is resolving back to the G, you probably wouldn't want to subsitute the Bm because it isn't a strong dominant and would change the feel of the song.)
salvatone - Posted - 05/14/2009: 08:11:28
At one time I took guitar lessons from the Great Burlington, Vermont guitarist, Paul Asbell. He suggested that you could substitute any chord with a root that was 2 tones up or down from the the root of the original chord in a harmonized scale. For G you would substitue Bm (2 up) or Em (2 down). For Bm you could use G or D. For Em you could substitute G or C. These chords all have tones in common.
But like any rule of chord substitution, it also has to sound good. Substituting a Bm for a G in bluegrass really suggests a Gmaj7, and you have to decide if a Gmaj7 is really what you want ot hear in Blue Ridge Cabin Home.
One way to find out is to play a substitution and see if everyone in the band turns around and looks at you.
Salvatone
Edited by - salvatone on 05/14/2009 08:14:33
pearcemusic - Posted - 05/14/2009: 09:12:43
substitutions aren't arbitrary or guesswork ....
for the most part, every sub that is ever to be played has already been played by someone somewhere.
In many cases we are lucky to have those subs documented, either in sheet music/chord chart form ... or in theoretical explanation in a curriculum of some type.
Function ... very important ... in dominant theory, the 3 and 7 are THE most important notes ... so the function of a dom7 is determined by those 2 notes.
1. i.e. in the case of a tritone sub, the 3 and 7 exist in the original chord .. let's say D7 (DF#AC) .... AND in the sub chord ... in this case Ab7 (AbCEbGb).
so the sub implies the same dominant harmony with an added b5b9 .... this is a true sub chord situation.
2. Bm (or Em) is not really a "sub" for Gmajor, but rather a partial extension ... there are no real altered harmonic tones from the original Gmajor ... but rather embellishments. You can play ANY modal triad over a Gmajor and get the same result ....
G, Am/G, Bm/G, C/G, D/G, Em/G, F#dim/G ... are all extensions of G major, not really subs.
and as RPM said ... they don't all work well all of the time.
for instance ... in a "bluesy" G bluegrass tune, the extensions for Gmajor wouldn't work very well ... because they ARE NOT BLUESY for the key of G
... BUT ... the modal triads for Bb or F start to give you a different set of bluesy sounds that DO work well in a G bluesy BG tune
Bb/G, Cm/G, Dm/G, Eb/G, F/G, Gm, Adim/G .... you get some nice combos from these bluesy extensions ...
F/G, Gm, Am/G, Bb/G, C/G, Dm/G,Edim/G ... also give a nice tonal palette to choose from.
The Pearce Family Bluegrass Band
www.pearcemusic.com
|
Feeds
