Being able to hear intervals is an important part
of becoming a better musician. It lets you play better by ear, play along with your
favorite CDs and MP3s, jamming with your friends, figuring out what others are playing and
much more.
Intervals are the units by which music can be measured. You could say that intervals are
to music what inches (or centimeters) are to carpentry. If a carpenter wants to know how
"things" fit together, he needs to understand how to measure those
"things". If a musician wants to know how music is put together, that musician
needs to understand intervals.
Intervals are defined by the Major scale. In other words, every aspect of music is
compared to the major scale to see how "things line up". Simply put, an interval
is the distance between two notes and the distances between the notes of the major scale
provide us with a reference point.
The Distance Between Pitches
The interval between two notes is the distance between the two pitches - in other words,
how much higher or lower one note is than the other. This concept is so important that it
is almost impossible to talk about scales, chords, harmonic progression, cadence, or
dissonance without referring to intervals. So if you want to learn music theory, it would
be a good idea to spend some time practicing identifying intervals.
When musicians talk about ear, they don't mean the sense organ itself so much as the
brain's ability to perceive, distinguish, and understand what the ear has heard. The term
ear training refers to teaching musicians to recognize information about the notes and
chords that they are hearing.
A few people have what is called
perfect pitch or absolute pitch. These people, when they hear music, can tell you exactly
what they are hearing: the G above middle C, for example, or the first inversion of an F
minor chord. A few musicians with particularly perceptive ears can even tell you that a
piano is tuned a few cents higher than the one that they play on at home.
However, most musicians can be trained to
recognize relative pitch. In other words, if you play two notes, they can tell you that
one of them is a major third higher than the other. If you play four chords in a row, they
can tell you that you played a tonic-subdominant-dominant seventh-tonic (I-IV-V7-I) chord
progression.
Fortunately, having relative pitch is good
enough, and for many musicians may even be more useful than perfect pitch, because of the
way Western music is conceived. Since all major keys are so similar, a piece in a major
key will sound almost exactly the same whether you play it in C major or D major. The
thing that matters is not what note you start on, but how all the notes are related to
each other and to the "home" note (the tonic) of the key. If someone really
wants the piece to be in a different key (because it's easier to sing or play in that key,
or just because they want it to sound higher or lower), the whole thing can be transposed,
but the only difference that would make (in the sound) is that the entire piece will sound
higher or lower. Most listeners would not even notice the difference, unless you played it
in both keys, one right after the other.
So, you often don't need to know exactly what notes or chords are being played. Simply
having an ear well-trained in "relative pitch" is extremely useful in many ways.
Guitar and piano players can figure out chord progressions just by listening to them, and
then play the progressions in their favorite keys. Other instrumentalists can play a
favorite tune without a written copy of it, just by knowing what the interval to the next
note must be. Composers and music arrangers can jot down a piece of music without having
to "pick it out" on an instrument to find the notes and chords they want. And of
course, ear training is crucial to any musician who wants to play jazz or any type of
improvisation. Given a well-trained "ear", any musical idea that you
"hear" in your head, you can play. And ear training is also crucial for those
interested in music theory, musicology, or just being able to write down a tune
accurately.
Intervals have a number and a
prefix. The number represents the number of pitch names (A,B,C,D,E,F,G) from the first to
the second pitch. For example, the whole step F to G contains two pitch names, F and G.
This interval is called a second. The interval from F to A contains F, G and A; three
pitches. This interval is therefore called a third. The trend continues through to the
interval containing eight pitch names. An interval containing eight pitch positions (from
A to A or from G to G) is called an octave. An interval from one pitch to the exact same
pitch is called a unison. The diagram below shows a C major scale. The intervals are
marked.
The second part of an interval
name is based on the quality of the interval. It is referred to as the prefix.
Perfect intervals include the
unison and the octave. Perfect intervals also include fourths and fifths. Perfect
intervals are labeled with a capital "P."
The Major prefix is only used for
seconds, thirds, sixths and sevenths. Major intervals are labeled with a large
"M."
Minor intervals occur when a
major interval is made one half step smaller. This can be done by raising the bottom note
or lowering the top note. Minor intervals are labeled with a small "m."
Augmented intervals are when a
major or perfect interval is made one half step larger, and the interval number does not
change. Augmented intervals are labeled with an "A," the abbreviation
"Aug.," or a "+." For example, above, if the P5 from C to G were
changed to a C to G#, it would become an augmented fifth, or +5.
Diminished intervals are created
when a perfect or minor interval is made one half step smaller and the interval number is
not changed. Diminished intervals are labeled with a "d," the abbreviations
"dim" or "deg," or a "°." For example, if the perfect fifth
from C to G above were changed to a C to Gb, the interval would become a diminished fifth,
or °5.
Thus unisons, fourths, fifths,
and octaves can be diminished, perfect, or augmented. Seconds, thirds, sixths, and
sevenths can be diminished (only if the interval is decreased by two half steps, such as
with a double flat), minor, major, or augmented.
Here are some examples of how
this system works:
P1- This is perfect unison.
M7- This is a major seventh.
m2- This is a minor second.
A6, Aug. 6, +6 - These are all
augmented sixths.
d3, deg.5, dim. 5, °5 - These are
all diminished fifths.
Consonance and Dissonance
Consonant intervals are intervals
that are stable. These intervals require no resolution. The consonant intervals are P1,
m3, M3, P5, M6, and P8. All other intervals within the octave are said to be dissonant.
Dissonant intervals are tense, and require resolution.
Enharmonic Intervals
Enharmonic intervals are
intervals that sound the same but are "spelled" differently. These intervals
result from the inclusion of enharmonic equivalents.
The most common enharmonic
intervals are the diminished fifth and the augmented fourth, shown below. These two
intervals divide the octave into two equal parts. These intervals contain three whole
steps, for this reason these intervals are referred to as the tritone.
When an interval is inverted, the
lower tone is raised one octave. The table below shows some intervals and their
inversions.
Intervals and their
inversions.
The Interval
When Inverted becomes
Unisons
Octaves
2nds
7ths
3rds
6ths
4ths
5ths
5ths
4ths
6ths
3rds
7ths
2nds
Octaves
Unisons
Perfect
Perfect
Major
Minor
Minor
Major
Diminished
Augmented
Augmented
Diminished
Compound Intervals
Compound intervals are intervals
that span distances greater than an octave. These intervals are often labeled as their
simple equivalents, as if an octave had been removed from the interval. The actual, or
compound, interval name is only used if it is very important to stress the actual interval
size.
Identifying Intervals
The easiest way to find an
interval's name is to first, count all the pitch names present, including the notes
themselves (ignore sharps and flats at this point). Then, find out (had it been missing a
flat or sharp) what type of interval it would be, depending on whether it is perfect (a
1,4,5,8) or major (2,6,7). If there are no sharps or flats, you are done. If there are,
figure out if the flat or sharp decreases or increases the distance between the two
pitches. If it increases the distance, the interval is augmented. If it decreases the
distance, and the interval would otherwise be perfect, it is diminished. If it decreases
the distance and the interval would otherwise be major, it is minor.