MIDI and Control

MAT 200B

Andrés Cabrera

Before MIDI

Before MIDI

Before MIDI

Propietary interfaces (e.g. DCB)

http://machines.hyperreal.org/features/before-midi.html

MIDI

Musical Instrument Digital Interface

Dave Smith from Sequential Circuits proposed this standard at the Audio Engineering Society show in November 1981

January 1983 Winter NAMM Show, Smith was able to demonstrate a MIDI connection between his Prophet 600 analog synthesizer and a Roland JP-6

http://en.wikipedia.org/wiki/MIDI

MIDI

MIDI

MIDI Controllers and modules

MIDI modules

MIDI Protocol

MIDI Data

• MIDI data is enconded using 7-bits
  
• or groups of 7 bits
• 1 bit is used for status/data identification
• 7-bit resolution => range 0-127
• This range is mapped to "musical" values
• notes
• middle C = 60
• each value is a semitone

MIDI Sequencers

Standard MIDI files

Once computer sequencers were available,

it was clear that a format for storing MIDI files on disk was needed.

MIDI has no timing information!

So the Standard MIDI file (SMF) adds this

before each MIDI message

in the form of time deltas to previous message

Standard MIDI file

Type I:

Single track

Type II:

Multi-track

Type III:

Multi sequence

MIDI files became ubiquitous in Karaoke machines and ring tones

General MIDI

Another addition to the MIDI standard to standardize instrument types and sounds

http://en.wikipedia.org/wiki/General_MIDI

Other forms of control

Several have been proposed

but the only one that has caught on is OSC

(Open Sound Control)

OSC

• OSC is a content format developed at CNMAT by Adrian Freed and Matt Wright
• Transport independent, although frequently implemented using the UDP protocol over ethernet.
  
• OSC messages consist of an Address pattern, a Type tag string, Arguments and an optional time tag
• Has not replaced MIDI, but now available in many systems including large propietary ones.