8: MIDI: N
, R
Many devices, especially hardware keyboards, have the ability to act both as
controllers (producing MIDI control data) and as receivers (producing sound,
video, or some other event).
Of course, the real joy of MIDI isn’t just the ability to use one piece of
equipment or software to control another: it’s the fact that you can record
and edit MIDI events. Any device with the ability to record and play back
MIDI is considered a sequencer. This includes both hardware keyboards with
built-in sequencers and the MIDI sequencers integrated within DAWs like
Cubase, Pro Tools, and Live.
Sequencing MIDI data lets you record, edit, and arrange compositions.
You might use sequencing as a simple writing tool for recording ideas and
adjusting and arranging them, or to create instrumental performances so
complex that you couldn’t play them in real time. Since MIDI stores only
event information and not sound, it’s possible to make edits with MIDI
that are difficult or impossible with audio recordings. For example, you can
change a recorded part to another instrument, make quick, fine-tuned pitch
adjustments without having to select audio waveforms, draw in unplayable
notes and rhythms, or make radical alterations to tempo.
What if you’re all virtual”?
You might think that MIDI doesn’t concern you,
because you make music directly in software and don’t have a controller. Well, think
again: if you’re playing a virtual instrument in a DAW or loop-based “virtual studio,”
youre using MIDI every time you click with the pencil tool to add a note. If anyone
tells you,“MIDI is dead,” theyre wrong—for now, at least. (See the sidebar “OSC: MIDI’s
Successor?” on p. 324.)
Connecting Instruments and Devices
USB and FireWire
Connecting a USB or FireWire MIDI device to your computer is basically
plug-and-play. Connect the USB or FireWire cable to your computer, as in
Figure 8.2, and your software should recognize the device automatically.
(Some devices require driver installation first.) If you have more devices,
Is it live, or is it
Sequencers work well for
recording and editing,
but MIDI is also useful
onstage. Because MIDI
data is simple and stan-
dardized, its easy to
build everything from
basic real-time trans-
posers to sophisticated
interactive setups. MIDI
effects in sequencers or
modular MIDI systems
like Max/MSP, Jade, Pure
Data (Pd), Reaktor, and
Logic’s Environments let
you create custom per-
formance rigs that work
as you play.
, O
just plug them in via USB or FireWire ports as well. If you’re out of USB
ports, connect a USB hub (making sure your devices have enough power),
and you’re done.
5-pin MIDI
Now that computers are ubiquitous in music-making and an increasing
number of instruments include onboard USB or FireWire ports, you may
use MIDI happily for years without ever plugging in a standard 5-pin MIDI
cable. However, there’s still a lot of equipment that uses 5-pin MIDI ports,
and since the port hasn’t changed since its introduction over two decades
ago, a wide range of new and old gear is available for computer-based music.
Connecting MIDI to a computer does require some additional steps. Since
computers lack MIDI ports (unless you have an internal interface with
onboard MIDI), you’ll need a separate piece of hardware to make the con-
nection. Many audio interfaces have built-in MIDI ports, as do some
USB- and FireWire-connected instruments, so you can connect your MIDI
equipment to one of these devices, and then connect that USB or FireWire
device to your computer. If you lack an audio interface or USB- or FireWire
instrument with a MIDI port, you’ll need a USB-to-MIDI adapter like the
Figure 8.2 If your device
has a USB or FireWire port,
you can plug it directly into
your computer. If you have
MIDI ports, too, as on this
Novation X-Station, you can
use them to connect addi-
tional equipment,
even if it
lacks USB and FireWire
puter connections, and then
use all your gear and instru-
ments simultaneously.
8: MIDI: N
, R
M-Audio Uno (Figure 8.3). The Uno has only one in and one out port; if
you have a lot of MIDI gear, a multiport MIDI interface becomes desirable.
Gear with standard 5-pin MIDI ports also requires a different cabling
arrangement than connections like USB. MIDI is unidirectional (data flows
in only one direction within a given cable). If you have two devices and you
want each to be able to receive information from the other, you’ll need
two cables.
The three basic MIDI connections are in, out, and thru (Figure 8.4):
In: Receives MIDI data from external sources.
Out: Transmits MIDI data originating within the device to external
Thru: Repeats whatever messages are received at the in port—thus,
messages from an external source (like a computer) travel “thru” the
device to any connected gear.
Figure 8.3 The M-Audio Uno
MIDI interface is so compact
you could easily mistake it for
a cable.With USB at one end
and MIDI at the other, it’s an
easy way of connecting a
MIDI device to your computer.

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