Glenn Tipton - Judas Priest. 'Nuff Said!

Ever notice how power chords, even when played with a clean tone in a blues song, just sound so right? Ever wonder why a major chord sounds so much more concrete than a minor chord? Ever have trouble hearing that F# played over a C chord, thinking it’s just a touch “off?”

The answer is much more than just the style of music you like or who is playing the chord. The answer has to do with the naturally-occurring series of harmonic frequencies that are generated when any single note is played. The answer lies in the multiples of a fundamental tone and their vibrations, spread out over several octaves and with ever-diminishing clarity.

The answer, is the Overtone Series.

You can cue up the imperial army music here if you like for effect, though the reality is that the concept of the overtone series is quite simple to grasp and once understood will really help further your knowledge of music.

Good, Good, Good… Good Vibrations

The Beach Boys had it right; it’s all about good vibrations. When a note is played, it vibrates as a waveform. For example, the note “A440″ — which is the standard tuning note in Western music — vibrates at 440 cycles per second. When that note is played, however, a series of other tones, sympathetic tones, perhaps (my explanation, not necessarily a proven scientific fact), also resonates. In essence, one note actually creates several notes. Take a look at the music staff below, which illustrates the order in which the overtones of a given note occur:

If play the note ‘C’, a naturally-occurring ‘G’ located a perfect fifth higher is also produced.  (If you don’t understand the intervalic relationships between pitches, I suggest you read my intervals music theory lesson first.) Above that another ‘C’ note an octave higher than the fundamental tone is heard. Continuing up you hear another ‘C’ note two octaves higher, then a third (‘E’), a fifth (‘G’), a b7 (‘Bb’ – and an approximate pitch), etc.

Please bear in mind that this is a very over-simplified explanation. It’s enough to get you started, but there is a bit more to it. Quite frankly, the “bit more to it” is bland and boring, and we Fretheads are all about fun and zaniness, right? (Yeah, right…)

Back to that Power Chord

To get back to my article opener about the power chord, you can see just by looking at the music staff that the interval of a fifth (the same interval that power chords are made of) sound very strong if for nothing else than they happen naturally. The same principle is also why a major triad sounds so heavy and grounded than other types of triads.

So I suggest you break out that Gibson Explorer that’s been sitting in your closet, crank up the Marshall stack, and start rockin’ out to Living After Midnight right away!