2008年10月31日星期五

Lesson 14: Names of Diatonic Notes

Before, learning any chords, it is important to know the difference between a diatonic note and a chromatic note.

A diatonic note is defined as a note that is in the major scale of the specified key. E.g. E is a diatonic note in the key of C (C-D-E-F-G-A-B), and Bb is a diatonic note in the key of F (F-G-A-Bb-C-D-E), etc. Any note that are not diatonic are considered chromatic. E.g. all the black keys are considered chromatic in the key of C, since the scale of C major consists of white keys only.

There are 7 notes (do-re-mi-fa-so-la-ti) in a diatonic scale; each of them has its function and characteristic, and therefore, have its own "technical names":
- First note (do): Tonic
- Second note (re): Supertonic
- Third note (mi): Mediant
- Fourth note (fa): Subdominant
- Fifth note (so): Dominant
- Sixth note (la): Submediant
- Seventh note (ti): Leading tone

It is important to know how to relate the names of all the diatonic notes to the intervals between them. E.g. the interval between the tonic and dominant is Perfect 5th, and the interval between the tonic and the leading tone is Major 7th. Can you figure out the intervals between the mediant and the submediant? And the interval between supertonic and leading tone? You can use the piano keyboard to help you figure out the intervals of all the possible combinations in the key of C (the simplest key). But ultimately, your goal is to be able to figure out all these intervals in all keys in a flash.

If you need a way to help you remember those names, try this:

- Think of tonic as the center,
- Supertonic is the note above tonic, and leading tone is the note leading to the tonic.
- The dominant is the 5th note above the tonic, and the subdominant is the 5th note below the tonic (i.e. the 4th note).
- The mediant is the middle point between the tonic and the dominant, and the submediant is the middle point between the subdominant and the tonic.

Does everything make more sense now??

2008年9月16日星期二

Lesson 13: 如何數拍子

Most songs have a time signature 拍號. Its time signature will be one of those that are introduced a few lessons ago, e.g. 4/4, 3/4, 6/8, etc. Each of these time signature has its own characteristics in sound, which is indicated by its strong beat 重拍. By listening to the downbeat of a song, one can distinguish the time signature of the song. As a musician, it is extremely important to be able to "hear" the time signature of a song, especially when you are to play a song without a score. Also, a musician must be able to count the beats of a song correctly so that he/she can play it in the way it is supposed to sound.

Here is how each time signature should sound like:
  1. 4/4:   ONE     two     THREE     four
  2. 3/4 or 3/8:   ONE     two     three
  3. 2/4 or 2/2:   ONE     two
  4. 6/8 or 6/4:   [ONE     two     three]     [TWO     two     three
  5. 9/8 or 9/4:   [ONE     two     three]     [TWO     two     three]     [THREE     two     three]
The bolded ONE is always a strong beat 重拍, no matter what time signature the song is. In the 4/4 time signature, THREE is considered a semi-strong beat 半重拍, so it is not as strong as the first beat, but still stronger than 2nd and 4th beat.  In compound time signature, you should be able to hear the 1-2-3 in each beat. Sometimes, songs in compound time can sound like this: one-one-two, one-one-two (where one is long and two is short). This is called the swing pattern, which is commonly heard in Jazz. A song that has this pattern is most likely in compound time, but you would still have to figure out whether it is 6/8, 9/8, or 12/8 by listening to the strong beat. 

2008年7月21日星期一

Lesson 12: 音程 (Intervals), Part 2

This lesson will cover more advanced topics in "intervals".

Enharmonic (異符同音) intervals

It is important to note that the interval number is determined by how the two notes are spelled. E.g. the interval between D and F# is major 3rd, but the interval between D and Gb is diminished 4th. Even though F# and Gb are the same note on the keyboard, because they are spelt differently, they need to be written differently (F is a 3rd and G is a 4th in D major). This applies not only to the upper note, but to the root as well. E.g. the interval between F# and C is diminished 5th, but the interval between Gb and C is augmented 4th.

Inversion of intervals

To invert an interval, simply raise the lower note by one octave. That will bring it above the upper note, and making the upper note the root note. After the notes are inverted, the interval between the new root note and upper note can be determined the way described before.

There is also a shortcut to determine the inverted interval. The interval number of the inverted interval is always equal to 9 minus the original interval number. What about the quality of interval? Here is the rule for inverting intervals (try to verify it yourself!):


Major becomes minor, and vice versa
Augmented becomes diminished, and vice versa
Perfect stays perfect


E.g. the interval from C to A is major 6th, so the interval number of the inverted interval (from A to C) is 9 – 6 = 3. And using the rule above, the inverted interval should be a minor interval. Therefore, the interval from A to C should be minor 3rd.
Compound interval

Up to this point, we have only considered intervals that are not more than an octave. In reality, intervals can go beyond an octave. To determine any interval that is greater than an octave, simply follow the following steps:
  1. raise the root note by one octave (or lower the upper note by one octave), so that the notes are now less than an octave apart
  2. determine the interval between the notes as described previously
  3. add 7 to the interval number to get the actual interval

E.g. to determine the interval between C and high E, we first determine the interval from C to E, which is major 3rd. So, the actual interval is major 10th after we add 7 to the interval number.

Lesson 11: 音程 (Intervals), Part 1

The term "intervals" (音程) refers to the distance between two notes. It can also be considered as the difference in pitches (or frequency) between two notes. The concept of intervals is very important, because they are the building blocks of chords.


There are two types of intervals in music: melodic interval and harmonic interval. Melodic interval is the interval between two notes when they are played one after another. Harmonic interval is the interval between two notes when they are played simultaneously (e.g. in a chord). In both cases, the lower-pitched note is called the “root”, and the interval is always defined as the interval from the root to the upper note.


Melodic interval:



Harmonic Interval:

Calculating intervals

To determine the interval between two notes, you always start from the root and count the number of steps to the upper note. Consider the root as the “doh” of the scale, and determine which note in the scale the upper note is. E.g. to determine the interval between F and A, we start with F as the “doh” of the scale (i.e. F major), then A is “mi” (the 3rd note) in F major.


The interval number is the number of degree of the upper note in the key of the root. So, in the previous example, A is a 3rd above F, or you can say that F and A are a 3rd apart. (doh = unison, re = 2nd, mi = 3rd, fa = 4th, so = 5th, la = 6th, ti = 7th, doh’ = 8th/octave)

But the interval number alone is not sufficient to describe an interval. We need to specify the quality (型態) of interval between F and A (quality of interval). If the upper note is actually IN the major scale of the key of the root, then the interval is either perfect (純音程) (unison, 4th, 5th, octave) or major (大音程) (2nd, 3rd, 6th, 7th). Let’s look at the example again. Since A is in the scale of F major, and it is the 3rd note of the scale, so the interval from F to A is major 3rd.

For a note that is NOT in the major scale of the key of the root, you can determine the quality of interval by counting how many semitone (or half step) it is above or below the note that is in the scale. Here are the qualities of interval that are not major nor perfect:
- augmented (增音程): one semitone larger than a major/perfect interval
- minor (小音程): one semitone smaller than a major interval
- diminished (減音程): two semitones smaller than a major interval, or one semitone smaller than a perfect/minor interval.

Can you tell the intervals between the following pairs of notes? (leave your answers in the comments)
- F and Ab
- F and A#
- F and Abb

In summary, just remember that unison, fourth, fifth, and octave can be (from low to high pitch) diminished, perfect, augmented; whereas second, third, sixth, and seventh can be diminished, minor, major, augmented.

2008年2月28日星期四

Lesson 10: 三連音(Triplets)

In addition to the different note values introduced in Lesson 5 and Lesson 6, there is a special class of notes that occurs frequently in both classical music and contemporary music, called the triplets (三連音). As the name suggests, it is used when you want to divide a duration into 3 equal subdivisions in any simple time signature.

Triplets are used whenever you want to divide any duration into 3 equal parts in a simple time signature, because in any simple time signature, the beats can only be divided into 2, 4,... equal subdivisions (power of 2, basically).

In a simple time signature, usually two quarter notes equal to one half note; and three triplet quarter notes equal to one half note (two normal quarter notes). Similarly, three triplet eighth notes would be equal to one quarter note (i.e. two normal eighth notes). Triplets are usually written with a number '3' above or below the notes. Sometimes, you will see a square bracket or a slur across the triplet, and sometimes only the number is seen. Rests and dotted notes can be used as needed in triplets. This is one of the common ways to write triplets:


Triplets can also be considered the building blocks of compound time signatures, because all beats in compound time signatures are divided into 3 equal subdivisions. E.g. in the common time signature (4/4), if all four beats are written as triplets, it will be equivalent to the compound key signature 12/8. Since all beats in compound time signature are triplets, they will not be labeled as triplets, and therefore, a beat in a compound time signature is a dotted quarter note, instead of a quarter note.

Optional:
There may be circumstances where we want to divide one beat (a dotted note) in a compound time signature into 2 equal subdivisions. To achieve that, a duplet is used. Two duplet eighth notes equal one dotted quarter note (i.e. 3 compound eighth notes). Theoretically, one beat can be divided into n equal subdivisions, by the use of tuplets (the general term for notes like duplets and triplets).

2008年2月12日星期二

Lesson 9: 拍號 (Time Signatures)

Time signatures typically consist of 2 numbers like in a fraction. It is always written after the key signature at the beginning of a piece, and will not be written again unless the time signature changes halfway in the piece (see Lesson 8). There are 3 types of time signatures: simple, compound, and complex. Each type of time signatures will be disccused below.

The two numbers in a simple time signature tell you the following information:



  • Top number: how many beats there are in a bar/measure.
  • Bottom number: what the value of one beat is, or the beat value.
E.g. Consider the time signature . The bottom number is 4, which means that each beat is a quarter note; the top number is 2, which means that there are 2 quarter notes in each measure. Similarly, the time signature means that there are 3 beats in each measure, and each beat is an eighth note. An important concept in simple time signature is that each beat can be divided into two subdivisions.



The most commonly used simple time signature is . Because it is so commonly used, it is sometimes written as 'C', which denotes 'the common time'.

In the second type of time signatures: compound time signatures, the numbers are read a little differently.
  • Top number: how many subdivisions there are in a bar/measure.
  • Bottom number: what the value/duration of one subdivision is.

So what is 'one beat' in a compound time signature? In compound time signatures, each beat is divided into three subdivisions (instead of 2 in simple time signatures). In other words, 'one beat' would be 3 times of a subdivided note in a compound time signature. This also implies that in all compound time signatures, the top number should be divisible by 3 (except for cases like 3/4 or 3/8, because technically it is pointless to have only 1 beat per measure). This is how you can distinguish between simple and compound time signatures.

E.g. The time signature means that each subdivision is an eighth note (bottom number), and there are 6 subdivisions in each measure, meaning there are 6/3 = 2 beats per measure. One beat in this time signature would be a dotted quarter note, because it is 3 times of an eighth note. Similarly, the time signature means there are now 9 subdivisions per measure, which means there are 9/3 = 3 beats per measure. Note that in all compound time signatures, 'a beat' will always be a dotted note.



The third type of time signatures, complex time signatures, are a lot less encountered than simple and compound time signatures. It typically involves a prime number (other than 2 and 3) on the top. E.g. 5/4 or 7/4. In these complex time signatures, a measure can be interpreted differently according to the composer. E.g. for the case of 5/4, the 5 beats can be played as 3+2 or 2+3, and in the case of 7/4, a measure can be divided into 4+3 or 2+3+2, etc.

Things to learn in this lesson:

  1. What do the numbers in a time signature stand for?
  2. Be able to differentiate between simple, compound, and complex time signatures.
  3. What are the differences between simple and compound time signatures?

2008年2月6日星期三

Lesson 8: 如何讀譜 (Reading piano scores)

The few most important things that you will need to pay attention to when playing songs/pieces are those illustrated in the following diagram:

  • Clefs: Most worship songs that you will encounter will have treble clef on top and bass clef at the bottom. However, in classical music, it is not uncommon to have either all treble clefs or all bass clefs for both hands, so it is always good to check.
  • Key signature: This tells you what key the song is in. The key signature is shown on all the staffs throughout the piece. The key of a song can change in the middle of it, so it is important to pay attention to such changes.
  • Time signature: This tells you how many beats are there in each measure (or bar). However, this is completely unrelated to the tempo (speed) of the piece. A more extensive explanation on how to read time signature will be covered in later lessons.
  • Bar lines: A bar line is drawn to separate measures. E.g. each bar has 4 beats in a given song, then a bar line will be drawn every 4 beats.

In addition to the components mentioned above, there are also other components that define the song/piece. For example,

  • the tempo of the piece is typically written at the beginning of a piece, above the 1st line.
  • the dynamics (relative loudness) of the piece can be written anywhere in the piece and changes as the piece goes.
  • there are also a wide variation of words used in music to mark the mood in the piece.