Intervals in Context Speed Drills Intervals are so important to music theory that it is important to identify them quickly. These pages contain tips and drills for quick identification of intervals in context. These drills are designed to be done quickly, and gradually increase in complexity.
Odd and Even Intervals As a good error-checking method, any interval in which both notes are in spaces or both notes are on lines, the interval is an odd number. Any interval in which one note is on a line and the other is in a space is an even-numbered interval. Identify the following intervals as odd [O] or even [E] – ignore other details for now!
The five-line staff is intended to cover the comfortable singing range of an average voice of a given type, and spans approximately one octave (so, incidentally, does the length of a note stem). So, for odd intervals, a third covers less than half of the staff (and looks like the bottom two balls of a snowman); a fifth covers about half of the staff (and looks like a snowman without the middle ball); the seventh fills about a full staff, and the ninth exceeds the width of a staff. Identify the following odd intervals by number – do not worry about distinctions like major/minor/perfect.
Similarly, for even intervals, seconds are very small, and overlap with each other (so they are not placed in a vertical stack, but are offset); fourths span half of the staff; sixths cross most of the staff; and octaves span the whole staff. Identify the following even intervals by number – do not worry about distinctions like major/minor/perfect.
Combine apparent size with oddness/evenness to identify the following intervals by number – do not worry about distinctions like major/minor/perfect.
Important Interval Types and Key Signatures The goal here is to quickly recognise the intervals that we use the most – this means primarily seconds, thirds, and fifths (note that these rules can cover fourths, sixths, and sevenths by inversion). Ultimately, these should all be memorised. In the meantime, there are some tricks, many of which are based on the key signature. You should always pay special attention to the last two accidentals in a key signature, though others will also come in to play.
Seconds: In a standard key of seven notes, there are seven seconds. Most of these are major, but two are minor, and the location of these is important for music theory in many ways. In major keys, they appear between scale degrees – and – ; in minor keys, these are – and – . However, we can simplify by looking at the key signature that they both share: the minor seconds (semitones) are always above the last two sharps in the key signature or below the last two flats in the key signature.
3 4
7 8
2 3
5 6
Circle the minor seconds. Pay attention to the key signature.
Fifths: The circle of fifths should be memorised as soon as possible. However, the mnemonic used for key signatures (Father Charles Goes Down And Ends Battle) can give us a lot more information that just key signatures. In a standard key of seven notes, there are seven fifths, and all but one are perfect (the last is diminished). Any fifth where both notes are of the same type (i.e., both sharp, both natural, or both flat) that appear in order in the Father Charles mnemonic will be perfect. The only fifths of this kind that are not perfect are those between B’s and F’s, because B and F do not appear in order in the mnemonic. Circle only the Perfect Fifths.
Fifths, cont’d: The one diminished fifth in any key is also extremely important in music theory. It appears between scale degrees – in major and – in minor. Once again, it is easier from the key signature: it always appears between the last accidental of the key signature and the next note that would need an accidental in the next key signature. For example, in the key of G-Major (or e-minor), the last accidental is F-sharp, and the next key in sequence (D-Major or b-minor) would then add a C-sharp. Since the C is still natural in G-Major, the diminished fifth is between F-sharp and C-natural.
7 4
2 6
Circle the Diminished Fifths. Pay attention to the key signature.
Note: The harmonic minor adds an extra diminished fifth between 7 – 4, the same place as in major – but it is clearly indicated by extra accidentals. The melodic minor can add one more, but it is seldom used, and is likewise indicated by accidentals.
Thirds: Thirds are harder than seconds and fifths, but are critical for chord theory and are worth learning. They can be memorised by learning all four augmented triads and all three diminished seventh chords, or by memorising the cycle of thirds (a cycle of fifths with a third inserted between each fifth, like C – e – G – b – D – f# – A, etc.). But there are also rules to do with scale degree and key signature. The key signature rule says that the last four sharps of a key signature have a minor third above them, and the last four flats of a key signature have a major third above them. However, this requires a key signature of at least four accidentals. The rules for a scale degree are a little more complicated, but since they are almost identical to the rules for chords in a scale, it is well worth learning them now: the perfect scale degrees ( , , and – tonic and {sub}dominants) carry above them the same type of third as the mode of the scale (major scales have major thirds in these places, minor scales have minor thirds in these places); scale degrees and ({sub}mediants) as well as scale degree carry the opposite type of third; scale degree always carries a minor third.
14
5
3
7
6
2
Identify the following thirds. Pay attention to Key. Scale degrees are given.
As with fifths, the harmonic minor will alter this pattern, creating a major third on 5 and a minor third on 7; this will be reflected in the accidentals. The same is effectively true for melodic minor.
Single Accidentals Chains of accidentals will have the effect of essentially changing the key, and cause too many exceptions to make useful rules. However, an interval that contains a single accidental makes for a fairly simple guideline: in general, a single sharp will cause the diatonic notes above it to be minor or diminished, and the notes below it to be major or augmented; a single flat will cause the notes above it to be major or augmented, and the notes below it to be minor or diminished. Normally, this means that intervals that are normally major or minor intervals (seconds, thirds, sixths, sevenths) will switch from major to minor and vice-versa, and intervals that are normally perfect will become augmented or diminished. In theory, there are lots of exceptions, especially creating diminished thirds, etc.; however, since these intervals are rare and carefully controlled in the common practice period, the rule is surprisingly accurate in practice (you will learn the exceptions eventually, but you need not be concerned with them now). Treat naturals as sharps in a flat key and flats in a sharp key. There is one important exception that you do need to know now: raising the last flat of a key signature or lowering the last sharp – in other words, cancelling the last accidental of the key signature – will cause that note to participate in perfect fourths and fifths against the next accidental in sequence (but will still create augmented and diminished fourths and fifths against the previous accidental in sequence). Double-check fourths and fifths involving the last accidental of the key signature. The quality (major/minor/perfect/augmented/diminished) of the following intervals can all be inferred from the accidentals, irrespective of key signature. Identify these intervals as quickly as possible.
The following tune is loosely adapted from a familiar song. Using all the strategies given above, identify all the melodic intervals except the (ubiquitous) major seconds.
