musical triad

Discussion in 'Art & Culture' started by curioucity, Oct 25, 2003.

  1. curioucity Unbelievable and odd Registered Senior Member


    I'm wondering about the function of each tone in a triad. Let say I'm taking the C E G major triad as an example. What are the functions of C, E, and G respectively to the overall sound? I am aware that omitting any of them will change how the triad sounds, but in what way, I can't say....
  2. Google AdSense Guest Advertisement

    to hide all adverts.
  3. Congrats Bartok Fiend Registered Senior Member

    Well, basically- if you take any note out of a triad, it ceases to be triad. As well, in a C+ triad, C will always be the root, E will always be the 3rd, and G will always be the 5th. If the 3rd is moved to the bottom, the chord is put into 1st inversion (6). If the 5th is moved to the bottom, it is in 2nd inversion (6-4). That's the quality of the triad, and the only to discern between different qualities is to play the chords yourself.

    In 7th chords (triad + 7th), the C+7 chord (CEGB), the chord can be changed by removing a note, as that would result in a triad. As well, if the 7th of that chord, B, was changed to B flat, the chord would become a C Dominant 7th chord. It all depends on the intervals between the degrees. ramble...

    Hope it helped.
  4. Google AdSense Guest Advertisement

    to hide all adverts.
  5. curioucity Unbelievable and odd Registered Senior Member

    well, at least there's some info on that, thanks.
    I once pressed C E G and compared it to C G. Oddly enough, it seemed that C G was enough to represent C E G (somewhat).... maybe that's confusing.... sorry if so, I can't describe it well...
  6. Google AdSense Guest Advertisement

    to hide all adverts.
  7. Canute Registered Senior Member

    You're not dreaming, your just listening well. C and G is enough to 'represent' the triad. In fact the C alone is enough.

    Triads are structured around natural overtones, the tones that are naturally related to the fundamental vibration. Thus, when you play the C (on a piano say) the vibration of the whole string will produce the fundamental C and that is the loudest tone you hear. However you will also hear the C an 8ve above. This is the first harmonic, created by the the vibration of half the string, and less loud than the fundamental.

    To cut the story short the string vibrates alonng all sorts of whole number lengths, producing all sorts on tones (think of the ambiguous tonality of a church bell - same thing). The first few of the series of harmonics above a fundamental C contains G and E. This is not a coincidence, it is why we have triads.

    If you follow the evolution of Western music it pretty much charts the introduction of the harmonic series into the chordal harmonies themselves. First people used octaves and fifths (plainsong etc). Then came the thirds (the 'consonance Angloise' introduced by the Brits hurrah), then the seventh and ninth, ('Classical' perod), then the thirteenth, fifteenth and all that jazz. (This is only rough).

    So you're right. When you play C and G you do hear E (although it takes a bit of practice to really pick it out)

    The 'function' of each tone within the triad is obviously to make it sound a certain way. If you listen carefully you'll hear that Cand G together create a very stable, settled and 'bare' sound. However adding the E creates a degree of dissonace. It sweetens the sound but also makes it less settled. (This is why for a long time, even while adding a third to the harmonies was allowable during a piece, it remained the practice to end with a bare fifth or 8ve since adding the third made the final chord sound less final, less 'satisfactory'. The E was heard as a dissonance. As Congrats says the precise arrangement of notes in the chord makes a big difference.

    The other way of looking at the function of the notes of the triad is linearly, their place in the horizontal flow of the music. In most circumstances in 'diatonic' music (music in a key) notes have a tendency to lead to other notes (depending on context). This is easily heard if you play a C major chord a few times then play a note B. It will want to go up to the C to resolve. This is an important function that the B note plays in the (dominant) G major chord, it drives to chord to 'resolve' to C major.

    Now play the C chord again and then the note F. It will want to move down to the E. This is the source of the traditional 'suspension' of church music, where a chord of F preceeds a chord of C, but the F (which has a real drive towards the E) is held on over the C chord and resolved late (not giving you what you want straight away, or a 'contradiction of expectation'). This is all easy to hear if you try it.

    Thus notes have both a horizontal function and a vertical one. For the absolute integration and control of these two functions at all times you can't do better than listen to J.S. Bach. But it's just the same for Eminem.

    It's an interesting subject.

  8. curioucity Unbelievable and odd Registered Senior Member

    Thanks for the info, though frankly I need time to digest them all (not because of the length, but my mediocrity in many things).
    I'll try experimenting some things you noted, maybe it will help.
  9. Canute Registered Senior Member

    It's not as tricky as it seems if you try just listening to the notes. Try it on the guitar also. I'm not sure how much you know, but if on the guitar you play a harmonic at the 12th fret what you hear is the first harmonic, (the octave above the fundamental).

    This is because your finger is stopping the whole string from vibrating (silencing the fundamental) but allowing each half of it to vibrate (half the string therefore double the frequency therefore the note an octave above). You can do this at quarter (5th fret) and a third (7th fret) of the string length also, for different overtones.

    This is what fascinated Pythagoras.
  10. curioucity Unbelievable and odd Registered Senior Member

    Gee, how ancient. I've never thought that music research has lasted for that long.......
    And for the guitar practice, okay... though I'm severe at playng guitar, but what you mentioned are merely 'sound test', right?
  11. Quantum Quack Life's a tease... Valued Senior Member

    I know given the information supplied so far this may sound kinda trite.

    But for me in the CEG triad the E is what makes it move, as stated it adds a certain dissonance and this gives the chord a character or feel if you like that suggests a chord may follow.

    If one flattens the E we get a minor chord. Which i feel shows how much influence the E or Third has........

    BUt as already said musical harmonics have great influences and I may add harmonic natures are found evrywhere in the physical and metaphysical realities. Resonances and sympathetic or empathic relationships are fundemental to life as a whole.

    Emotions etc can be described in harmonic terms... in fact why the music feels the way it does is because you are reacting to the music in a harmonic or sympathic way..... Strikes a chord so to speak. this is my view and i'm sure it is shared by others
  12. Canute Registered Senior Member

    Music is very closely related to mathematics and physics. All our modern ideas about waves, frequencies, amplitudes etc come originally from study into musical sounds and vibrating strings. Musical harmony is just mathematics. If two tones sound good together it's because our brains can figure out of the mathematical relationship between their frequencies.

    The main thing to realise is that when a string is plucked it vibrates in all sorts of ways at the same time, and therefore it produces a complex waveform made up of many different frequencies and amplitudes. If this wasn't true then musical instruments would produce sine waves, which would be horribly boring to listen to.

    This is the problem that electronic instrument makers have to overcome. The complex natural relationships between harmonics have to be faked. Even now most electronic instruments are harmonically very boring compared to the real thing. This is why synthesised pianos are usually only interesting to listen to for about two minutes, whereas a real one is interesting forever. It's also a big part of the reason that, for instance, a flute sounds different to an oboe.

    It's also why electric guitarists often prefer to use valve amplifiers (valves produce natural harmonics) rather than digital ones.
  13. curioucity Unbelievable and odd Registered Senior Member

    Understood, thank you.
  14. curioucity Unbelievable and odd Registered Senior Member

    By the way, (not to be taken seriously, hahaha, this is merely fun) I once played a string of music with all triads.... I mean, I replace every single tone with triad..... try to imagine how messy it sounds....

    Oh, by the way, (NOW this is serious) I once played this 'somewhat triadish melody', here it is (note that groups separated by dash are to be played apart)
    C - EG - EG - C - EG - EG - B - Df - B - DF - C
    Is it considered such?
  15. Canute Registered Senior Member

    All notes within a scale can be harmonised by a triad made up from that scale, so it is pretty normal practice to harmonise melodies with triads, although not normally one per note.

    Yous chord progression is basically C major and G7. Add in F major and you've got what's been the fundamental basis of western harmony for the last 500 years. (Chords based on the first, fourth and fifth degrees of the scale).

    G7 is a triad built on G but with an extra third added so is a four note chord (although they don't all have to be played - e.g. you played the B-D-F without the G at the bottom. Try adding it and you'll find it's the right bass note).

    (This is a bit of an oversimplification but true enough).
  16. BigBlueHead Great Tealnoggin! Registered Senior Member

    Erm... Canute... E above middle C is not a harmonic of middle C. I believe the fourth harmonic of middle C would be an E, but it would be an octave higher. The CEG triad isn't properly represented by the CG fifth chord.

    Also, by playing two notes that are a tone or half-tone apart, you can usually generate a noticeable "beat" - that is, interference between the two notes. This discordant sound can be used to good effect musically, but the CEG triad does not automatically make musical sense with notes like D or F.
  17. curioucity Unbelievable and odd Registered Senior Member

    Nice info, thanks. Looks like I got some histories of music as well.
  18. Canute Registered Senior Member

    Quite right. But getting the general priciple is the first thing.

    Curiocity could hear the E. I explained why.

    The beating between notes is too subtle for most musical use, and most people can't hear it at all without practice.

    I don't know quite what you mean here. The CEG triad doesn't include a D or F. If you play CDG or CFG you will hear the tendency of the the D or the F to move to the E. That was my point.

Share This Page