Monday, May 4, 2009

Rhythm basics

Disclaimer: The information presented in this section is to get a general appreciation of the concepts. They are by no means complete or accurate.

This section is not meant to be a musicology type explanation, but simplified to appreciate rhythms that are used in film music so that one can appreciate Raja’s rhythms.

Timing is everything in music, more so with rhythms. Rhythms are expressed as time signatures and it typically is written like a fraction – example 3/4, 4/4 or 6/8.

What does this fraction mean?

The numerator shows you the number of beats in each measure

The denominator tells you which note gets one beat.

Now, what is a measure? A measure (sometimes called a bar) is any segment of written music.

So, what does 6/8 mean? In a measure (or bar), you can count 6 beats. That explains the numerator. What about the denominator? It means that one eight of a note gets one beat.

Similarly, in a 3/4 rhythm, you can count 3 beats in a bar. One fourth of a note gets one beat. Obviously, the 6/8 rhythm is faster than the 3/4 rhythm. In other words, the greater the denominator, the faster is the rhythm.

Time signatures such as 3/4 or 3/8, 4/4, 2/4 are considered simple time signatures.

4/4 is the Western time signature for Aadhi Thaalam.

3/4 in Western music is called the Waltz rhythm (we briefly covered some examples in the section Thaalagathi vendum). This is called theesram in Carnatic music.

2/4 is typically a March rhythm.

Time signatures such as 6/8, 9/8, 12/8 are considered compound time signatures. Note that the numerator is always divisible by 3 in these cases.

6/8 rhythm is the roopaka thaalam in Carnatic music.

9/8 rhythm is called Sangeernam in Carnatic music.

6/8 in the Western world is used in fast waltzes, 12/8 in 12-bar blues and doo-wop music.

The third type of time signature is called Asymmetric or complex or irregular time signatures and these include signatures such as 5/4, 5/8, 5/16.

There is a whole genre of western rock music called math rock that tries to use complex time signatures such as 7/8, 11/8, 13/8 and so on.

5/8 is widely used in Carnatic music (kanda chapu) and so is 7/8 (misra chapu) are considered complex by the Western world.

Also, another great resource on odd time signature that carries a great tutorial…

Odd Time Signatures

I am sure some of you are sweating with this heavy lifting music theory stuff. Rest assured, we will stay clear of such heavy topics for some time!


Vignesh Subramanian said...

Dear Ravi:

A good primer on time signatures.

When you say
"The denominator tells you which note gets one beat", I am not sure what it means...

Anyway here is how I understand it: the denominator explains the basic gene of the time signature, while the numerator tells you how many such genes are in this DNA..
i.e, denomitor defines the nature/ duration of the count that makes the measure while the numerator defines the measure itself (i.e., how many counts made this measure).

To illustrate practically, if you run a 4/4 measure 3 times you get a total of 12 counts. Here you pegged the marker at the end of the 4th, 8th and 12th Count; Instead, during the same 12 counts, if you pegged the marker at the end of 3rd count, 6th count 9th count and the 12th count , you would be left with 4 cycles of 3/4;

Or in other words, in the above experiment, both 3 cycles of 4/4 and 4 cycles of 3/4 shared the same gene (which is 1/4th of a count) as well as the same DNA (which is one count made of 4 times 1/4th note); But they differ in their replication pattern. Thats all :-)

In Carnatic terms this gene is called one Maathra; And 4 maathras make one Aksharam (which is the DNA); So 3 cycles of 4/4 had 4 aksharams per cycle while the 4 cycles of 3/4 had 3 aksharams per cycle.Important point to note here is: the duration of mathra that made the Aksharam as well as the duration of each aksharam itself are exactly the same in both cases.
This phenomenon is best explained in the song "Aagaya Vennilaave" where the nadai is basically:
"Tha ka dhi mi
Tha ka dhi mi
Tha ka dhi mi"
Where as Tha Ka Dhi mi = 1 aksharam
and "tha" = 1 maathra;

So this song feels a 4/4 (i.e., a Chatusra Ekha Thaalam or an Aadhi talam depending on your metronome) while the song is actually a 3/4 (i.e., Roopakam)

Sorry for mini-blogging in your comment area.. but hope that compliments your observations..

With Love

ravinat said...

Thanks Vicky for your additional commentary. Pretty useful insight.

Also, sorry about oversight in not responding to this for such a long time.

I did not have email notification for comments at that time.


Saravana kumar said...

Talking about time signature crotchet - means 1 count (represented as 4 in the denominator).
minim - means 2 count (represented as 2 in the denominator).
quaver - means 1/2 count (represented as 8 in the denominator).
Now 3/4 means 3 crotchets in a bar.
6/8 means 6 quavers in a bar.
3/2 means 3 minim in a bar.
I have shared this up to my knowledge.
Thank you.

Emmanuel Raj said...

Any example of 5/8 song please

ravinat said...

Emmanuel Raj.

There are several in Raja's work. This is also known as Kanda Chapu or simply kandam. Here are some top of mind examples:

1. Azahgu Malarada (Vaidehi KaathirunthaaL)
2. Mazhai Varudhu Mazhai Varudhu Kudai
3. Poovai Virinngu (Adharvam - Malayalam)
4. Kalyana Maalai Kondadum Penne (PP Arthangal)