Time Signatures - problem understanding

[ggpianogg]

Hi everyone,

I'm really hoping someone can shed some light on this for me, since I've watched about a dozen videos and read about a dozen articles and still can't understand it (none of the videos / articles addresses my issue).

Now, I understand what the "top number" means (how many beats there are per measure). I understand what the bottom number is (which note gets one beat). What I don't understand though, is how this differs in PRACTICE. What I'm reading/hearing everywhere, is that the difference between, for example, 4/4 and 4/8, is that the second one would be twice as fast as the first one. I'm failing to imagine this in practice unfortunately.

I think the best way for me to explain my concern is with a very easy example. If someone could explain to me the difference between how one and the other would sound, I'd be extremely appreciative.

I drew this in paint and on a laptop touch pad, so please excuse the quality



What is the difference in practice (in the way it would sound) between the two melodies?

[angelislayer]

I think one reason why you may be failing to understand the difference is because you have to understand that tempo and meter are two distinct and totally different things. In your example you show two melodies which are identical in that you have two measures being divided into four beats. One with quarter notes and one with eighth notes. Four beats is four beats so the melodies would play exactly the same. The only reason why one might play faster than the other is wholly dependent upon what tempo you designate or begin at for each individually. Other than that there really is no difference. The only time you would definitely hear eighth notes play twice as fast as quarter notes is  when they are written under the same time signature and tempo.

[quantum]

As in your example above, there is no difference (and there is nothing incorrect about that).  With time signatures there can be multiple methods of describing the same rhythm.  As angelislayer alludes, tempo is more defined by a tempo indication rather than time signature.  

Some composers have used this temporal-metrical relationship within their music.  Take Beethoven for example.  Often times you may see notes of smaller values for slow pieces and notes with larger values with fast pieces.  Compare the Op. 111 Arietta with the 9th Symphony 2nd movement.  

***

If you are just a beginner don't worry too much about the following.  You'll be exposed to it as you learn more.  

In the big picture, we can categorize metre with the following:
Simple, compound, additive, pulsatile, free.

The differentiation between simple and compound are the subdivisions of a single beat.  In simple time beats are divisible by two; in compound beats are divisible by three.

If Simple or compound, music can be described by the number of beats per bar:
Duple, triple, quadruple.


Eg: All of the following are simple triple:
3/2, 3/4, 3/8, 3/16
The difference is visual - whether the composer chooses to use smaller or larger note values.  However, the feel of the metre would be the same.  

The example you illustrated above would be simple quadruple.

[ggpianogg]

Hey guys,

Many thanks for your answers and help on this one.

So basically, for the time being (since I'm a total beginner and I'd like to move on with my studies - I've been caught up in this detail for 3 days now ), can I assume that the difference that the bottom number makes in a time signature has only to do with the way the notes on the sheet music LOOK, more than with how the song actually sounds?