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2008年12月17日星期三

Lesson 17: Tempo (速度)

Tempo is an Italian word for "speed". It is typically specified at the beginning of a piece. The tempo of a piece defines its mood and difficulty to play. It is very common in classical music to have changes of tempo or mood (or both) in the middle of the piece, although this is less common contemporary worship music. In contemporary worship music, the tempo changes usually take place when we want to flow to the next song flawlessly.

Tempo is either given in words or in beats per minute (BPM). All classical music described their tempos in words, because the metronome (拍子機) was not invented back then. Although the modern prints of most classical music would include the mathematical tempo (BPM) as well, for convenience. Here are some examples of tempo markings:
  • Largo: very slow (最缓板)
  • Allegro: fast and bright (快板)
  • "♪ = 120": 120 eighth notes per minute

As a member in a worship team (whether you are singing or playing an instrument), it is very important to learn how to keep a steady tempo, because the congregation will have a hard time following an unsteady tempo. The person playing the instruments may not notice that he/she is playing at an unsteady tempo, especially if he/she is playing something that unfamiliar, because he/she is focused on trying to figure out what to play next, and not keeping count of the beats.

The key to learn how to keep a steady tempo is: practise, practise, PRACTISE! Your ultimate goal is to be able to keep a steady tempo inside you. Here are some suggestions:

  • Know the songs well: listen to it over and over again, and try to count the beats while listening. It is even better if you can figure out its time signature and count accordingly. (In my opinion, “knowing a song well” means you are able to sing that song with accurate rhythm and melody when you are not listening to it.)
  • Practise with a metronome: start from a slow tempo first and slowly increase it to the level you want. You must play the song WITH RHYTHM even at the slowest tempo, NEVER play the easier part faster and the harder part slower, because that will only make it harder for you to learn the rhythm in the whole song. (You should keep doing this until you can start to keep a steady tempo on your own.)
  • Play along with the CD/MP3: to practice songs for which you have the CDs or MP3s, you can play the song on your CD player or computer, and then try to play the chords on your instrument simultaneously, matching the chords in the song itself. One good thing about playing along is that the CD or MP3 will not stop for your mistakes, so you are forced to keep moving on. This is the best way to learn how to respond to your own mistakes without lagging a beat in real time. However, it is not very helpful to do this exercise when you are not familiar with the song yet.

At the end of the lesson, I want to stress the distinction between tempo and time duration of notes (see Lesson 5 and Lesson 6). The tempo of a song and the length of a note are two completely different concepts, and should not be regarded as the same concept at any time.

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1月22日星期二

Lesson 6: 音符時值...續集 (Note duration, cont'd)

Having just the whole note, half note, quarter note, eighth note, etc. are not sufficient for expressing more complicated rhythm in most classical or contemporary music. E.g. how do you write 3 beats? There must be a way in music to do that. In fact, there is more than a way!

Dotted Notes
When you add a dot to a note, you add half of its value to the note. E.g. a quarter note is normally 1 beat, so a dotted quarter note would last 1.5 beats. Similarly, a half note is typically 2 beats, adding a dot to it (dotted half note) would make it 2 + 2/2 = 3 beats!

Tie
A tie can occur between two or more notes to add all their values together. E.g. when a quarter note is tied to a half note, then the result would be 2 + 1 = 3 beats. When a quarter note is tied to a sixteenth note, the result would be 1.25 beats. The tie is also used when a note is being stretched across measures.

There are also times in music when nothing is to be played. These periods of silence need to be properly notated as well, thus the need for another class of symbols: rests (休止符).
Just like the notes shown in Lesson 5, there are whole rest, half rest, quarter rest, etc... the duration of which corresponds to their respective notes.


Whole rest



Half rest



Quarter rest



Eighth rest



Sixteenth rest


Rests are also similar to notes in the way that both rests and notes can be dotted. E.g. a dotted quarter rest stands for a rest of 1.5 beats. However, ties cannot be used on rests.


Questions for this lesson:

  1. Do you know how to write all the notes/rests presented in this lesson?
  2. Can you name all the different notes/rests at sight?
  3. Can you calculate the total duration of a string of notes/rests?

2008年1月15日星期二

Lesson 5: 音符時值 (Note duration)

This lesson will teach you about the duration (or length) of different notes. It is really important to know how long each note lasts, because these notes are the building blocks of all songs! If you do not know how long each note last, you will not be able to read the melody in the right rhythm.

Each note that looks different has a different duration in music. The first note presented is called the whole note (全音符):

The whole note usually represents 4 beats. Cases where a whole note does not represent 4 beats will be discussed in later lessons. The whole note is also known as the semibreve.

The second note presented is called the half note (二分音符):

The half note looks like a whole note with a stem attached to its side. Since a half note is literally half of the whole note, it usually represents 2 beats.



As you may guess, the next note that is presented is called the quarter note (四分音符):

The quarter note looks like the half note, but with a solid note head. The quarter note usually represents 1 beat.


If this keeps going. the next note presented would be the eighth note (八分音符):

The eighth note looks like the quarter note with a tail at the end of the stem. It usually represents half a beat.

Is there a sixteenth note (十六分音符)? YES! And it is written by simply adding an additional tail to the eighth note. So, the sixteenth note has two tails at the end of the stem as follows.


As you can see, each time a tail is added to the note, its duration is halved. Therefore, you can create thirty-second note (三十二分音符), sixty-fourth note (六十四分音符), even hundred twenty-eighth note (一百二十八分音符) by adding a tail each time you half a note. However, for the practical purpose of playing the piano for worship purposes, we almost never see anything that is thirty-second note or shorter (thank goodness!).

If all these notes seem overwhelming, just remember that they are basically math equations. In this math system, the whole note is 1, and everything else is a fraction of the whole note. Thus, as long as you can remember the name, you can remember its duration:

whole note = 2 x half (1/2) notes = 4 x quarter (1/4) notes = 8 x eighth (1/8) notes = 16 x sixteenth (1/16) notes... etc.

From now on, you should be able to calculate how many beats are there in the example below:

It is 2 + 1/2 + 1/2 + 1 = 4 beats.

Questions you should be able to answer at the end of this lesson:

  1. Do you know how to write all the notes presented in this lesson?
  2. Can you name all the different notes at sight?
  3. Do you know the relative duration of all the different notes? (e.g. how many half notes equal to a whole note?)
  4. Can you calculate the total duration of a string of notes?