Meter is the term used to identify the measured quality of music. When we listen to music that is measured or metrical, we may be aware that there is more than one pulse rate present. That is, we may be able to tap at more than one speed as we listen. In fact, it is not unusual to hear four or five pulse speeds flowing simultaneously. We will refer to each of these as a pulse stream. The flow of several simultaneously-sounding pulse streams may be represented as a series of dots here shown on five levels (A, B, C, D and E), the top level representing the slowest pulse (See Example 3).
Ex. 3. Pulse Streams occurring simultaneously at five different speeds
The pulse relationships above can represent a whole piece. There are only two complete spans or cycles shown by this dot structure, identifiable by the pulse stream at level A.
Listen to an example chosen by your instructor. 1. Write down a series of dots on paper to represent the pulse stream that’s easiest to hear at a comfortable speed. (A half dozen or so dots spaced about an inch apart should do.) 2. Put an arrow to the left of this stream to show that it is the beat*. 3. Next tap a pulse stream you hear that is faster or slower than your beat. Represent a slower pulse by a series of dots above your beat, or a faster pulse by a series of dots below your beat. 4. Be sure to determine and represent accurately the relationship of the faster or slower pulses to the original beat. Are the faster pulse streams twice or three times faster? Are the slower pulse streams twice or three times slower? 5. Continue adding levels until you have represented all the pulse streams you hear. You may number these to show the order in which you heard them.
*The terms "pulse" and "beat" are sometimes treated as synonyms; each can refer to a signal which marks off time into equal (regular or periodic) time spans. In this discussion, however, "beat" will refer to the periodic signal which is chosen as the easiest to express, and which is used as a point of reference for "pulses" on other levels. For a given measured passage with several pulse streams, one will be described as containing a series of beats, the others will be described as containing pulses marking off faster (shorter) or slower (longer) units of time. While an essential feature of meter itself is the potential existence of several pulse streams, the term "meter" is often used in a more limited sense to refer only to the beat and its immediate grouping into 2s, 3s, and its immediate division into 2s or 3s. ________________________________________________________________________
Example 4 represents hearing a pulse-stream structure containing four levels—the beat level with one slower level and two faster levels. Levels A, C, and D are numbered to show the order in which they were notated by an assumed listener. This example may or may not represent what you heard.
Your instructor chose an example in which all the pulse streams are related by 2's; that is, each level is twice as slow or twice as fast as the one immediately above or below it (Triple pulse streams, with 3:1 relationships—three times faster or three times slower— will be taken up later). It is inaccurate not to show these proportions in your dot structure. However, you may have chosen a different pulse stream as the beat, a different number of pulse streams, and a different order for the notation of the other levels.
Think about these differences and why they may have occurred. It could be that your attention was drawn first to some regularly recurring accent or emphasis (see below), or to some recurring pattern which established its own pulse through repetition. It is important to realize that as a listener you have control over some features of the music, such as the choice of beat speed and the order in which you attend to the other pulses, while other features, in this case, the binary proportions in the entire set of pulses, are inherent in the music itself.
The set of tappable pulses, with one pulse stream identified as the beat and one or more faster or slower simultaneously-sounding pulse streams related in 2:1 or 3:1 proportions, is the metric structure of a measured musical passage. Given your understanding of Ex. 4 above, we may shorten the definition to the following:
The metric structure of a piece of music is its set of tappable pulses.