Inside The Box - Roland MC-909 Getting Started Manual

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Inside the Box

A good example of this kind of conversation takes place right within your MC-909. The
MC-909's case actually holds several separate MIDI devices that are always yapping to each other.
Let's eavesdrop on one of these conversations, between the MC-909's VELOCITY PADS and its
sound generator. Here's what these two MIDI devices do:
• The VELOCITY PADS are the things you bang on with your fingers at the bottom edge of the
MC-909. They don't make any sounds all by themselves, they just produce MIDI messages.
• The sound generator is the part of the MC-909 that actually produces the notes you hear—in
fact, it produces audio.
Each time you strike a pad on the MC-909, the pad sends a MIDI message to the sound generator. If
you hit a pad that plays Middle C, for example, the pad sends the sound generator a MIDI message
that means, "Hey you, play a Middle C!" The sound generator plays a Middle C. When you let go of
the pad, the pad says, in MIDI talk, "That's enough. Stop playing Middle C," and the sound generator
stops playing Middle C.
MIDI is actually a very detailed language that allows all sorts of performance information to be
passed from one MIDI device to another. To you, it just feels like a simple thing: you hit a pad, you
hear a sound. But under the hood, it's really a team effort between multiple MIDI devices chatting
in MIDI talk, faithfully converting your playing into sound.
Sequencing
It's possible to capture and record these MIDI messages, and to play them back. That's what the
MC-909's "sequencer" does. The sequencer records MIDI messages you play into it—remembering
the order you played them in, as well as your timing—and plays them back at your command,
causing the sound generator to recreate your original performance.
You play the pads.
©
2003 Roland Corporation U.S.
Getting Started Guide
Sound
generator
The pads send
MIDI messages into
the sequencer.
Play this note.
Stop playing this note.
Play that note.
Stop playing that note.
MC-909 Getting Started Guide
D Beams
Sequencer
VELOCITY PADS
The sequencer ...and plays them
captures into the sound
the messages... generator.
Play this note.
Stop playing this note.
Play that note.
Play this note.
Stop playing that note.
Stop playing this note.
Play that note.
Stop playing that note.
Sampler
The sound generator
produces the notes.
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