MIDI
What it is, how we use it
When we connect a MIDI keyboard to a computer
that has MIDI software installed, all kinds of interesting possibilities
become available. These two screen shots below show first one of the ways
that music appears when saved as MIDI. Notice the similarity to a player
piano roll where the length of individual notes is represented by their
horizontal length, and their pitch is related to their vertical placement.
To the left is an image of a keyboard so that you can see where the notes
are in relation to the pitch of the keys. At this point, if we had a wrong
note somewhere, we could just click the mouse cursor on the note and move
it anywhere else on the graph where we'd want it. If a note was too short,
we could likewise click on it and make it longer (or shorter), and at
the bottom, where the vertical lines are, we could select an in-dividual
note and by making the vertical line taller, we would increase the volume
of that particular note. In the example shown, we wanted all of the notes
to have the same loudness, so the vertical lines are all the same height.
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Figure 5, left. This is a screen shot,
or picture of the computer screen showing one MIDI track. In this case,
it is the first several measures of the melody line of the "Jig"
Fugue, by Bach. Notice the horizontal lines re-presenting the individual
notes and the image of a keyboard to the left. The vertical lines at
the bottom of the screen represent the loudness of the individual notes.
In this view they are set to the same value, but they could be varied
if we wanted to accentuate certain notes over others. In the lower part
of the music "graph" area, there is a virtual transport control
panel, where we can operate the system somewhat like a tape recorder
in that we can play, record, reverse, or quickly go to the beginning
or end and also set the tempo and a loop function if we want the song
to play over automatically. Although hard to see in this picture, across
the top of the screen are a number of other functions that we can control.
Figure 6, right. Here is
another picture of the computer screen, this time showing the first lines
of the Jig Fugue melody as real music. Again you will see the virtual
transport con-troller. In this form, we can print out what we played as
actual sheet music. This is one of the many nice features of MIDI. If
you play some-thing into the system from a MIDI keyboard, you can easily
transform it into sheet music
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As you can begin to see from this, MIDI offers a musician many options.
In one sense you might, from a performer's viewpoint, almost consider
MIDI as a musical instrument in and of itself, an instrument with the
capabilities of control over many different aspects of the final song.
To use the correct terminology, every musical piece in MIDI is referred
to as a "song," even if the music in question is an instrumental
version of a classical number. Sections of songs are referred to as
"parts"
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