ABSTRACT
How MIDI Control Works 419 MIDI channels 419 Channel and system messages contrasted 419 Note on and note off messages 421 Velocity information 422 Running status 423 Polyphonic key pressure (aftertouch) 423 Control change 424 Channel modes 427 Program change 428 Channel aftertouch 429 Pitch bend wheel 430 System exclusive 430 Universal system exclusive messages 431 Tune request 432 Active sensing 432 Reset 432
MIDI Control of Sound Generators 433 MIDI note assignment in synthesizers and samplers 433 MIDI functions of sound generators 435 MIDI data buffers and latency 436 Handling of velocity and aftertouch data 436 Handling of controller messages 437 Voice selection 441
General MIDI 442 Scalable Polyphonic MIDI (SPMIDI) 444 RMID and XMF Files 445 MIDI over USB 446 MIDI over IEEE 1394 448 MIDI over Ethernet 448 Open Sound Control 449 Sequencing Software 450
Introduction 450 Tracks, channels, instruments and environments 451 Input and output fi lters 452 Timing resolution 453 Displaying, manipulating and editing information 453 Quantization of rhythm 455 Automation and non-note MIDI events 456 MIDI mixing and external control 457 Synchronization 458 Synchronized digital video 458
Audio Remote Control Using Computer Networks 459 Open control architecture 459
Actuators, sensors and blocks 461 AES64-2012 461
Types of message 463 EuCon 464
Node objects 466 Protocol 466 Processor types 467
Summary 468
MIDI is the Music Instrument Digital Interface, a control protocol and interface standard for electronic musical instruments which has also been used widely in other music and audio products. Although it is relatively dated by modern standards it is still used extensively, which is a testament to its simplicity and success. Even if the MIDI hardware interface is used less these days, either because more synthesis, sampling and processing takes place using software within the workstation, or because other data interfaces such as USB, Firewire and Ethernet are becoming popular, the original protocol for communicating events and other control information is still widely encountered. A lot of software that runs on computers uses MIDI as a basis for controlling the generation of sounds and external devices.
