It's been a busy year. I haven't posted for months and was only going to wish everyone a Merry Christmas but this thread caught my attention. I thought I might try to add some clarity the discussion.

Before I start what might be turn into a short novel,the short and simple answer to the original question "what is the difference between 3/4 and 6/8 time?"...is [b]3/4 time means there are 3 beats to the bar and 6/8 time means there are 2 beats to the bar. That's it!

So to my "novel"

Mac is right...you need to know the correct terminology and most importantly how the notes are grouped, to be able to identify the time signature of a bar of music or a whole piece.

You need to know that in Simple Time, the beats are plain,undotted beats be it crotchets(quarter notes),
minims(half notes) or whatever and can be subdivided into groups of 2

In Compound Times, the beats are dotted beats, dotted crotchet(dotted quarter notes), dotted quavers(dotted eighth notes), etc and can be subdivided into groups of 3

The correct terminology for Simple Times:

2/4 time is called Simple Duple Time, there are 2 crotchet(quarter note) beats to the bar.

3/4 time is called Simple Triple Time, there are 3 crotchet(quarter note) beats to the bar.

4/4 time is called Simple Quadruple Time, there are 4 crotchet(quarter note) beats to the bar.

C stands for 4/4 time as well and is also called Simple Quadruple Time.

We are all taught that the top number tells us how many beats are in the bar and the bottom number tells us what type of note gets 1 count. This is fine for Simple Time but not for Compound Times.

When I first introduce a piece in 6/8 time to a student and ask them what time do they think it is in, I know they are going to say "6 quaver (eighth note) beats to a bar". They are always puzzled when I say no...there are 2 dotted crotchet(quarter note) beats to a bar.

I go on to explain that this is a Compound Time, that there are 6 pulses in the bar, (thus the 6 on the top) but the 6 pulses are grouped into 2 dotted beats, each dotted beat having 3 pulses each.

I often use the analogy of 2 paddocks with 3 cows in each paddock, then tap the Duple rhythm counting 123 while left hand taps once only, and 456 while the right taps only only. The emphasis must be that while there are 6 pulses there are only 2 beats.
(Sometimes it's easier for younger students to count 123,123 or 1&u, 2&u or even something like but-ter-fly, but-ter-fly. Anything to make sure there are only 2 beats)


The correct terminology for Compound Times:

6/8 is called Compound Duple Time, there are 2 dotted crotchet(quarter note) beats to the bar.

9/8 is called Compound Triple Time, there are 3 dotted crotchet(quarter note) beats to a bar.

12/8 time is called Compound Quadruple Time, there are 4 dotted crotchet(quarter note) beats to a bar.


Often theory exams have bars of notes with no Time Signatures and students are asked to add the correct time signatures. The students need to know how the notes are grouped to be able to work out the time.

The "America" example discussed here shows clearly 2 different groupings of the quavers(eighth note). The 5th bar in the right hand, the quavers(eighth notes) are grouped into 2 lots of 3. This can only be 6/8 time. The next bar in the Left hand, the quavers(eighth notes) are grouped into 3 lots of 2 quavers(eighth note). This can only be 3/4 time. Nothing else!

The 6/8 time signature at the beginning of the example posted just means that overall the main time of the piece is 6/8.
The 3/4 bars add the energy and rhythmic variety to the piece. (Skillful writing!)

Whew! I think that's it. I can take of my "school marm" hat now. LOL

Oh, and Merry Christmas everyone!

yjoh

[i]Music...a joy for life.