cychan7570
Thx, Lynn. I am sure taste is a very important factor to decide when to add tension. However, I am trying to see if there are any principles or guidelines (jz like cooking where we need recipe - and the recipe can be modified according to taste). I have tried googling online for more info abt tis, but can't find any. Anyone know if there is a book I can refer to?
Yes, there certainly are common methods (harmonic devices if you will) used to create/increase tension.
First my apologies if some of this is rudimentary to you but I have no idea what your current understanding of theory is.
In any key there are seven chords that occur naturally, one for each note of the scale. Take C major for example:
C Dm Em F G Am B diminished (C)
These chords can be referred to as a chord-scale or a harmonized scale. You could sing do-re-mi etc as you played the chords.
In A major the notes would be different but the chords would follow the same order:
A Bm C#m D E F#m G# dim. (A)
These chords are often referred to in Roman Numeral form as I II III IV V VI VII (I) for the purposes of notating progressions. It makes them easier to transpose and to analyze.
Therefore a I-IV-V-I progression would indicate the chords C-F-G-C in the key of C major and A-D-E-A in the key of A major.
Chords can be classified into three groups in regards to the tension they produce in a key: Tonic (the least tension), Sub-dominant (more tension) and Dominant (the most tension). The function of each chord in a major key is as follows:
I. Tonic
II. Sub-dominant
III. Tonic
IV. Sub-dominant
V. Dominant
VI. Tonic (Relative Minor)
VII. Dominant
I. Tonic (the I chord again)
In other words, in the key of C major the C, Em and Am chords are Tonic and have the least tension. The Dm and F chords are Sub-dominant and have some tension. The G7 and B diminished chords are Dominant and have the most tension.
A progression like C-F-G-C is Tonic - Sub-dominant - Dominant - Tonic, a very natural increase and release of tension. The chord progression Am - Dm - Bdim. - Am is the same structure: Tonic - Sub-dominant - Dominant - Tonic. Even though it sounds sadder/darker it follows the same pattern of tension and release.
The chord most responsible for tension is generally the "V" chord (the 5 chord). The V chord is referred to as the "dominant" chord and often has an added 7th. For example, in the key of C major the V chord is G7. In the key of Dm, A7 is the V chord. "Altering" the V chord will create even more tension, for example, A7#9 or A7#5(flat9). A dominant chord can be "altered" with a sharp 5, a flat 5, a sharp 9 or a flat 9 (also a #11). "Extensions", for example adding a 4th, 6th, 9th etc., will add some tension but not nearly as much as an "alteration"". Generally speaking, an "altered dominant" has the most tension of all chords. An altered dominant is similiar to (actually identical to some) diminished chords. By now this probably sounds like a foreign language, sorry. But you asked!
You can add "extensions", like sus4 or add9, into any chord at any time as the amount of tension added is minimal and is truly just a matter of taste. To use tension effectively, however, it's good to know where in a progression the tension rises and falls and how to embellish that.
Typically this can be seen in cadences. For example in a I-IV-V-I progression (also considered a "cadence") the I chord (Tonic) has little or no tension, the IV chord (sub-dominant) creates more tension and the V chord (dominant) has the most tension, resolving back to I to release tension. In jazz the common cadence would be II-V-I or I-VI-II-V-I.
So in a jazz progression, for example, we may see something like this (a I-VI-II-V-I) :
Cmaj7 - Am11 - Dm9 - G7 - Cmaj7
In this case we would generally want to increase the tension on the V chord, the G7, so we would alter it and get something like this:
Cmaj7 - Am11 - Dm9 - G7(#5/b9) - Cmaj7
This can be very useful in composition. If you start on a Tonic chord there is the least tension. You can then go to another Tonic and there won't be a large increase in tension. If you move to a Sub-dominant, the II or IV chords, the tension increases. To decrease go back to a Tonic. To increase even more go to a Dominant. To start with tension immediately go to a Sub-dom. or dom. etc.
Keep in mind this is a very cursory explanation.
When to add tension is a debateable issue, obviously, as it depends on the situation. However, if you look at specific styles of music, pop vs classical vs jazz etc, there are certain traditions. Understanding the stylistic traditions (often found initially by studying cadences) helps one understand the mechanics of use.
Take a traditional 12 bar blues:
I IV I I
IV IV I I
V IV I V
Anytime you see the I chord there is little or no tension (Tonic)
Anytime you see the IV chord there is some tension (Sub-Dominant)
Anytime you see the V chord there is the most tension (Dominant)
Again, generally speaking, we would want to increase the tension on the IV and, especially, the V chords.
Now take a song like "Every Breath You Take" by the Police. There are "extensions" on almost every chord of the intro which add some tension to each chord yet the progression itself is most responsible for the overall tension:
A(add9) F#min(add9) D(add9) E(add9) A(add9)
This is a I-VI-IV-V-I progression. Clearly there is not a great deal of tension in the first two chords. There is some, and we feel some movement between the A(add9) and F#m(add9) chords even though they are both Tonic. When we hit the D(add9) chord the tension increases as it as a Sub-dominant chord. Then when we get to the E(add9) chord the tension is at it's highest as it is the Dominant chord. That is followed by the A(add9), the Tonic, which releases the tension.
Hard to recommend a specific book without knowing your current knowledge of music theory. A very safe bet would be "The Basis Of Music" which covers theory from simple notes thru harmonized scales. In fact, probably a must for any musician looking to brush up on basic music theory:
http://books.google.ca/books/about/The_Basis_of_Music.html?id=-M-WyBrwHJsC&redir_esc=y Meanwhile, look up the function of Tonic, Sub-dominant, and Dominant chords. And perhaps read about cadences as well. If you have questions about what I wrote or what you read elsewhere feel free to ask. If there is a specific progression you want to analyze just post it.
Cheers.
Edited to add even more confusion while I had late dinner)
post edited by SToons - 2012/07/27 03:32:22