Musical Instrument Digital Interface, - Hol.gr

The picture to the right
represent about ten
measures of MIDI notes for
one track. The analogy of a
player piano roll is used in
that the sequencer is
sending note information to
a synthesizer in the same
way that a piano roll sends
note information to the
player piano. An attractive
feature about a MIDI
sequencer is that if the
performance has a few
mistakes the notes may be
moved, made shorter or
stretched instead of having
to re-record the entire
section.
To the right is an
example of an
event listing of
note information.
Here the notes are
listed with their
location in each
measure as well
as position in
absolute time.
MIDI sequencers
include timing
information on
the tempo of the
composition.
MIDI events may
Another attractive feature of a
MIDI sequencer is the ability to
add control changes after the
recording. In the example to the
left the key velocity for each note
is represented in a graph. The user
may change the velocities with the
stroke of a pencil using a mouse.
Other control options include
program changes, pitch bend,
fader controls, modulation wheel,
panning, and many more.
Piano roll editing and graphic
editing is one way to manipulate
the MIDI data. It is possible to
view the same information in
notation form or in an event
listing.