all 41 comments

[–]kouhoutek 63 points64 points  (13 children)

When tones are played at the same time, their waves combine to form a complex wave. When the frequencies of those notes are in small ratios, like 2:1, 3:2, etc., the resulting wave is fairly simple and sounds pleasing. When the notes are in ratios involving larger numbers, like 16:15, the complex wave is more complicated and the sound is jarring and unpleasant.

An independent tritone is one that sounds pleasant and it suitable for ending a people piece. A dependant tritone is jarring and requires addition notes after it to "resolve" the music for the audience. They are often used to show alarm or distress. The diminished fifth, or the devil's triad, is an example of a dependant tritone.

[–]regular-human 84 points85 points  (5 children)

suitable for ending a people

Whoa, hey now....

[–]Lukavian 56 points57 points  (2 children)

Genocide: The Musical

[–]torpedoguy 0 points1 point  (0 children)

Sequel to Cannibal: The Musical?

[–]PutsTheAssInBass 5 points6 points  (1 child)

You're a rock star, get your game on

[–]tylerfb11 5 points6 points  (0 children)

Get slaaaaayed!

[–]BeautyAndGlamour 2 points3 points  (1 child)

Just a footnote: The waves are not complex mathematically.

[–]kouhoutek 0 points1 point  (0 children)

Composite wave is probably a more precise term.

[–]minus_minus 1 point2 points  (0 children)

This guy resonates.

[–]Mositius [score hidden]  (3 children)

What is an "independent/dependent tritone" supposed to be? Literally never heard of it, and a google search just turns up this thread.

[–]kouhoutek [score hidden]  (2 children)

In music, there is the concept of resolution. When you start a piece at with a certain note or key, your ear "wants" to eventually return to it. This is true with consonance vs. dissonance as well. Music can use dissonant chords like the diminished 5th, but it needs to return to consonance or it will feel incomplete. Finishing on a dependent tritone is like starting an anology but

[–]Mositius [score hidden]  (1 child)

Yeah I get all that, just what do you mean by (in)dependent in this context?

You mean like a blues scale tonic seventh chord (with tritone between 3 and 7) is stable and thus the tritone "independent"? or do you mean something else entirely?

[–]kouhoutek [score hidden]  (0 children)

It simply means you can't end on a dependent tritone. It depends on additional notes and chords to achieve resolution else the music will sound incomplete.

Whether a particular tritone is dependent or not is more of a matter of opinion and history than anything. There are some measurements you can apply to the resulting sound wave to say whether it is more or less consonant, but at the end of the day music is an aesthetic, and opinions will vary.

[–]henstepl 9 points10 points  (0 children)

Harmony is sourced from (closeness to) small close-integer ratios of frequency, where close-integers are only distanced by 1.

A perfect fifth is nearly 3/2, a perfect fourth is nearly 4/3, a major third is nearly 5/4, and they all have consonance. A major second is close to 9/8, which isn't all that small of integer. A minor second is not close to anything nicer than 16/15, but it is still useful in music.

A tritone is the square root of two, 1.414213...

That's not close to anything! It transcends dissonance, it is "ambiguous" because there is no closeness to any small close-integer ratio on which to evaluate it.

If you use a tritone, a diminished fifth, an augmented fourth, it will make the listener uncomfortable. You'd better be going for that.

[–]BassoonHero[🍰] 6 points7 points  (4 children)

In music, the “pitch” of a note refers to how “high” or “low” it sounds. Pitch corresponds to the frequency of a note (although the exact relationship has a couple of caveats).

We say that two pitches are “consonant” if the ratio of their frequencies is a simple fraction, and “dissonant” if the ratio is not a simple fraction. We care about this because our brains do — consonance might sound nice, stable, or pleasant, while dissonance may sound tense, unstable, or grating. In music, we use both of these effects.

In music, we call the ratio between the frequencies of two pitches the “interval” between the pitches. The simplest fraction (other than 1/1) is 1/2. We call the interval corresponding to this ratio the “octave”. Our brain likes octaves so much that two pitches separated by an octave sound very similar, though we can tell that one is higher and the other is lower.

In music, we say that pitches separated by octaves are in the same “pitch class”. In Western music, we use twelve different pitch classes. (The reason for this is interesting, but it's outside the scope of this answer.) In modern times, we consider all twelve of these pitch classes to be equally spaced.

With twelve pitch classes, we can form twelve different intervals. The smallest (other than the unison) is the “semitone”. An example of a semitone is the interval from C to C♯ (or, equivalently, to D♭. Another example is the interval from E to F. Other intervals can be represented as multiples of a semitone: from zero semitones (a unison) to twelve semitones (a full octave, which is equivalent to a unison when talking about pitch classes).

Some of these intervals are very consonant. The most consonant is the unison/octave, followed by the “perfect fourth” (five semitones) and “perfect fifth” (seven semitones). Other intervals are very dissonant, including the semitone itself (also called the “minor second”) and the “tritone” (six semitones, also called an “augmented fourth” or “diminished fifth” based on context). Because the tritone is so dissonant, it often sticks out to the listener. It should be used judiciously (which does not always mean sparingly!).

If you ever take a course in music theory, you'll hear about many “rules” to obey when writing music. These rules, prohibiting things like “parallel fifths”, are really practical guidelines; breaking them thoughtlessly will likely sound bad. The tritone itself has sometimes been fancifully called “the devil's interval”, although what was surely a hyperbolic description of its dissonance has taken a life of its own over the years. There is no evidence that this moniker was ever taken seriously in a religious sense, or that use of the interval was outlawed. It is, on the other hand, absolutely true that our standards of consonance and dissonance have mellowed over the years and that a listener from the year 1600 would likely have found the tritone interval much more grating than we do today — and that, therefore, a composer from that time would have used many fewer of them.

An important counterexample illustrates the point. One of the most important chords in common practice western music is the “dominant seventh chord”. This chord contains four notes, and two of them are separated by a tritone. The dissonance of this interval gives the chord a certain “tension”, and this tension is “resolved” when the dominant seventh chord is followed by a more consonant “tonic” chord. The most traditional, conservative way of ending a piece of music is with an “authentic cadence”, which often includes a dominant seventh chord. The lesson here is that even early composers did not avoid the tritone or dissonance in general; rather, they respected and often relied upon them.

Now, the disclaimer: I'm not an expert on early music (especially pre-Renaissance), so I'm open to input from someone with more specific expertise in that subject. Maybe there is some priest somewhere who once forbid the tritone in his church or something. Stranger things have happened.

[–]profHoneybee 0 points1 point  (3 children)

We say that two pitches are “consonant” if the ratio of their frequencies is a simple fraction, and “dissonant” if the ratio is not a simple fraction

and then there's the perfect fourth hanging out here being all smug like i dont follow your rules you dont know me

[–]BassoonHero[🍰] 0 points1 point  (2 children)

The perfect fourth is a 4:3 ratio – the next simplest after the 3:2 perfect fifth.

[–]profHoneybee 0 points1 point  (1 child)

hmm i guess you dont know that it's considered dissonant in western classical music tradition then

look it up :)

[–]BassoonHero[🍰] 0 points1 point  (0 children)

In modern times it is considered consonant. However, during the common practice period it was sometimes considered to be dissonant in certain circumstances: specifically a perfect fourth above the bass.

It's for this reason that the rules of common practice discourage chords in second inversion (i.e. with the fifth in the bass; e.g. G-C-E). There are several exceptions to the general rule: when the bass note is a passing tone, when used as part of some cadences, and so on. (The more you get into the weeds here, the more various authors would disagree or analyze the same situation slightly differently.)

Obviously, I'm simplifying the subject for the sake of ELI5. I omitted diatonic theory entirely. A minor third is consonant but an augmented second is dissonant, and so on.

[–]BeautyAndGlamour 1 point2 points  (0 children)

It's basically just two notes which sound "bad" together, creating an ominous vibe:

The two intro notes in YYZ have this interval. Some other examples off the top of my head:

The very first chords hit in One Winged Angel.

The very last chord in the Sailor Moon Opening.

The main riff in Eurythmics' Missionary Man does not follow this interval, but uses a "normal" one. However when the heavy metal band Ghost decided to cover it, they changed it to get a more evil sound.

[–]Sirsafari 4 points5 points  (0 children)

Devil triton is just a flatted 5th on any major chord. So for example a Cmaj chord (C-E-G) with a flatted 5th is C-E-F#.

For a true Devils Tritone I believe you only play the 3rd+5th(E-F#) and no root(C) with sometimes a dominant 7th for more dissonance (C-E-F#-A#)

That’s using Cmaj as an example

[–]MisterGoo 0 points1 point  (0 children)

I can't believe no one has mentioned my man Adam Neely yet... Here you are : https://youtu.be/eR5yzCH5CsM

[–]Jingocat 0 points1 point  (3 children)

I was taught it is called the devil's tritone because you can go up the tritone and down the tritone and both intervals are of equal value. Thus, as the song says, there are two paths you can go by. That, and it just plain sounds sinister.

[–]BonetoneJJ 1 point2 points  (2 children)

A tone is whole step. semitone is half step. Interval of Tri/ three tones creates diminished 5th augmented 4th.

[–]Jingocat 1 point2 points  (1 child)

That is absolutely correct. I was speaking to the reason it is called the devil's tritone.

[–]BonetoneJJ 1 point2 points  (0 children)

Yeah I think I replied to wrong comment

[–]hotmetalslugs -3 points-2 points  (1 child)

Hard to sing. Hard to sing meant your average joe couldn’t properly sing that interval melodically.

Average joe can’t sing it = it won’t be in church music.

Not in church music? Must be devil’s. Don’t sing it or you could be burned at the stake.

Yes we are a strange species.

[–]Birl42 0 points1 point  (0 children)

Don't know why this got downvotes. It's not inaccurate to my knowledge.