MIDI

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MIDI

• Musical Instrument Digital Interface

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What is MIDI?

• MIDI is an acronym for Musical Instrument Digital
  Interface.
• The term is used for both hardware and software.

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What is MIDI?

• MIDI protocol provides a standardized and
  efficient means of conveying musical performance
  information as electronic data.
• MIDI information is transmitted in "MIDI
  messages", that tell a synthesizer (or sound
  card) how to play a piece of music.

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What is MIDI?

• The MIDI specification allows for a maximum of 16
  channels of information to be sent from one MIDI
  device to another using a standard MIDI cable.
• This allows a MIDI sequencer to play back up to
  16 different channels of MIDI information that
  are entirely independent of each other.

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How do MIDI channels work?

• Assume a MIDI sequencer playing a multi-timbral
  sound module where channel 1 is playing a flute
  sound, channel 2 is playing a clarinet sound, and
  channel 3 is playing a harp sound. When the
  sequencer sends a pitch bend message on channel 3
  to the harp, only the harp receives the message
  the other 2 channels completely ignore it.

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What is a multi-timbral device?

• A Multi-timbral keyboard or sound module has the
  capability to receive MIDI information on more
  than one channel simultaneously. All General
  MIDI keyboards and sound modules, by definition,
  are multi-timbral.
• (Well discussion General MIDI later in this
  presentation.)

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A Brief History of MIDI

• It is important to remember that MIDI was created
  to simplify live performances. During the 1981
  fall convention of the Audio Engineering Society,
  Dave Smith and Chet Wood, two engineers from
  synthesizer manufacturer Sequential Circuits
  (creators of the popular Prophet-5 keyboard)
  proposed an industry standard for an electronic
  musical instrument interface. The idea was that
  performers should not have to create custom
  cables and devices to connect synthesizers.
  Instead, they should be able to "plug and play"
  with units from different manufacturers.

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A Brief History of MIDI

• Dubbed the Universal Synthesizer Interface (USI),
  this draft proposal was modified by the engineers
  of synthesizer manufacturers Oberheim, Roland,
  Korg, Yamaha, and others of their ilk. A
  consensus was orchestrated on the revised
  proposal and in late 1982 (drum-rolls please) the
  first set of universal MIDI specifications was
  adopted.

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A Brief History of MIDI

• A detailed history of MIDI is available on the
  class web site
• (Tutorials Page)

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MIDI is Everywhere

• Most film and TV scores, as well as popular
  recorded music is written and performed using
  electronic keyboards and other MIDI-equipped
  musical instruments. (Thanks to advances in
  digital sampling and synthesis technologies, the
  orchestra playing behind that big-screen block
  buster is more likely to be the product of MIDI
  than a real orchestra with dozens of acoustic
  instruments.)

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MIDI is Everywhere

• MIDI is also easy to find in the world of
  personal computing. If your computer has a sound
  card, it most likely also has the ability to play
  MIDI files (using a built-in hardware or software
  synthesizer that responds to MIDI messages), and
  with an adapter can also be connected directly to
  other MIDI-equipped products, allowing you to
  take advantage of various computer programs that
  can help you learn, play, create and enjoy music.

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MIDI is Everywhere

• MIDI also has some other interesting and popular
  uses. For example, MIDI Show Control is a command
  and control language used with rides at major
  theme parks and events at Las Vegas casinos, and
  MIDI Machine Control is used in recording studios
  to synchronize and remotely control recording
  equipment.

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MIDI is Everywhere

• MIDI is being used to generate ring tones in
  mobile phones. MIDI ring tones sound far better
  because they are polyphonic (play more than one
  note at one time) and because they use music
  synthesizers that produce a wider variety of
  sounds than previously possible.

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MIDI is Everywhere

• There are over 300 companies around the world
  making products that support MIDI -- well known
  companies such as Apple and Microsoft, Roland and
  Yamaha, Nokia and Sony/Ericsson, among others.

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MIDI is Everywhere

• Can you name other possible uses for, or
  applications of, MIDI technology?

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The Benefits of MIDI

• MIDI is a technology that represents music in
  digital form. Unlike other digital music
  technologies such as MP3 and CDs, MIDI messages
  contain individual instructions for playing each
  individual note of each individual instrument. So
  with MIDI it is actually possible to change just
  one note in a song, or to orchestrate an entire
  song with entirely different instruments.  

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The Benefits of MIDI

• Since each instrument in a MIDI performance is
  separate from the rest, its easy to "solo"
  (listen to just one) individual instruments and
  study them for educational purposes, or to mute
  individual instruments in a song so that you can
  play that part yourself.

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The Benefits of MIDI

• Play with a band
• Standard MIDI Files are available for many
  popular songs, and when used with a personal
  computer or digital piano make it possible to
  have an entire backing band play along with you
  at whatever speed (tempo) and in any pitch (key)
  you desire. MIDI files are perfect for practice,
  as well as for performing when additional
  musicians are not available.

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The Benefits of MIDI

• Record and edit your performance
• A MIDI Sequencer can record your performances for
  listening at a later time, and even save your
  performance in Standard MIDI File format for
  playback on other MIDI systems. A MIDI Sequencer
  is a way to evaluate your own progress or to
  study how someone else plays.
• Since all MIDI data is editable, you can edit any
  imperfections. If you play a wrong note, you can
  just change it using the Sequencer's editing
  tools. If you find you just can't play fast
  enough to keep up with the tempo, you can slow it
  down for recording and speed it back up for
  playback. 

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The Benefits of MIDI

• Compose Music
• Arrange and Orchestrate
• Educational Uses
• Auto-Accompaniment
• Recording Studio Equipment
• Song Files
• Standard MIDI Files ("SMF" or .mid files) are a
  popular source of music on the web, and for
  musicians performing in clubs who need a little
  extra accompaniment.
• Stage Lighting Controllers
• Many performing bands use MIDI to synchronize
  lighting cues with their music.

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The Benefits of MIDI

• Play any instrument
• Most digital pianos and other MIDI instruments
  come with hundreds of different sounds (pianos,
  trumpets, violins, guitars, basses, etc.) that
  you can play yourself or play via a MIDI
  sequencer to create orchestrated music. 

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General MIDI

• Most MIDI keyboards today include the General
  MIDI sound set, sometimes by themselves, but
  often with other sets of sounds. By having at
  least one standard set of sounds, files could now
  be exchanged and successfully played back on all
  GM compatible instruments.
• In most cases, the GM sound set is based on
  actual wave samples recorded from the original
  instruments. The difference in cost for a wave
  based sound card versus a synthesizer only sound
  card is minimal, and easily worth the difference.

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General MIDI

• The General MIDI specification includes which
  instruments should be played, how many MIDI
  channels the device must handle, and how many
  voices can be played back at the same time.
• MIDI Channels
• A General MIDI device must be able to
  simultaneously play back a different instrument
  or patch on each of its 16 channels. Drums and
  percussion instruments are always assigned to
  MIDI channel 10.

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General MIDI

• Instruments or Sounds
• The General MIDI sound set must include at least
  128 preset instruments in the exact order as
  specified in the GM Instrument Patch Map. There
  is also a specific GM Percussion Key Map based
  around 47 percussion sounds.
• Voices or Polyphony
• A General MIDI device must be able to play back
  at least 24 voices simultaneously divided between
  melodic and percussion instruments. These voices
  must be able to be dynamically allocated or
  assigned as needed. All voices must respond to
  velocity.

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General MIDI

• Channel Messages
• General MIDI devices must also support continuous
  controller messages including
• Channel Volume
• Modulation Wheel
• Velocity
• Panning
• Sustain
• Pitch bend
• Channel Pressure Expression.

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General MIDI

• There are 128 instruments arranged into 16
  families.
• Note that the instrument numbers shown on the
  next slide range from 1-128, though the actual
  value used in the MIDI Program Change messages
  will be 0-127.

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General MIDI
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General MIDI

• A complete listing of all 128 general MIDI sounds
  is locate on pages 8-10 of your MIDI tutorial
  (located on the class web site).

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General MIDI

• General MIDI drum sounds are found on Channel
  10. 
• General MIDI defines 47 drum sounds, with each
  being allocated to a separate MIDI key. The
  number before each drum sound corresponds to the
  keys on a 61-note MIDI keyboard

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General MIDI (Channel 10)
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General MIDI

• Where do I find these General MIDI sounds when
  using Finale?

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General MIDI

• Where do I find these General MIDI sounds when
  using Sibelius?

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General MIDI

• Even though the General MIDI specification lists
  which sounds are to be used, it does not define
  the way the sounds will be reproduced. This being
  the case, not all General MIDI synthesizers are
  created equal.
• MIDI keyboards and sound modules can
  significantly differ in sound quality. The same
  holds true for GM based PC sound cards. Some can
  produce amazing reproductions of the original
  instruments, while others do not succeed nearly
  as well.

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General MIDI

• Generally, you get what you pay for in terms of
  sound quality, although like all technology-based
  products, the investment needed to acquire great
  sounding instruments seems to get lower every
  week!

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Benefits of General MIDI

• Your Link To Compatibility With The Rest Of The
  World
• Predictable behavior!
• This alone makes GM extremely worthwhile in what
  can otherwise be a rather unpredictable
  environment. With a GM compatible instrument, you
  have an organized industry standard set of sounds
  from which to choose. It will be compatible with
  any commercial MIDI song files you may purchase,
  and your instrument will be compatible with those
  of your peers. Most software programs default to
  the GM sound list at start up, negating the need
  to create a custom sound list.

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Benefits of General MIDI

• The benefits of GM extend well beyond the
  individual user. Now, if you compose music using
  the GM instrument set, you can be confident that
  your MIDI songs can be enjoyed by anyone else who
  owns a General MIDI compatible instrument. Prior
  to GM, a MIDI song file would often prove useless
  to the recipient because of the wide variance of
  instrument assignments between different makes
  and models of MIDI instruments.
• The cooperative effort among manufacturers whose
  instruments support the General MIDI standard has
  catapulted the usefulness of MIDI into the
  mainstream of musical creativity.

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Beyond General MIDI

• In anticipation of greater demands from
  consumers, Roland and Yamaha developed
  "extensions" of General MIDI in their respective
  GS (general standard) and XG (extended general)
  MIDI instruments. These instruments are
  compatible with the GM standard, yet offer a
  variety of additional features, such as
  reverb/chorus effects and more instrument sounds
  over and above the basic GM specification.

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How to tell if an instrument is General MIDI
compatible

• Look for one (or more) of the following logos,
  either stamped or painted on the instrument
  itself, or on the owner's manual that came with
  the instrument.
• The instrument is General MIDI compatible if one
  or more of these logos are present.

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General MIDI Summation

• With general MIDI, one has a simplified,
  convenient means of composing, recording, and
  playback of music using software and a computer.
  The primary advantages of a general MIDI
  instrument are
• a consistent industry standard set of sounds from
  which to choose.
• compatibility with any commercial MIDI song files
  .
• assurance of compatibility with others who own a
  GM instrument.
• most software programs (including Finale
  Sibelius) will default to the general MIDI sound
  list at start-up.
• spending more time making music instead of
  serving as a "MIDI Technician" for non-General
  MIDI instruments!

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Creating a MIDI file using Finale

• Simply input the notation of your music the same
  way you have for your exercises and projects.
  When ready to create your MIDI file, choose SAVE
  AS from the File Menu.

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Creating a MIDI file using Finale

• Make sure that your file name contains NO SPACES
  or special characters, and is no more than 22
  characters in length (otherwise, it will not work
  within your web site). Under FORMAT, choose
  Standard MIDI. In the subsequent dialog box,
  choose Format 1, and click OK.

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Creating a MIDI file using Sibelius

• Again, make sure that your file name contains NO
  SPACES or special characters, and is no more than
  22 characters in length. Under FILEEXPORT,
  choose MIDI. Click SAVE.
• Thats it!

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Any Questions?

• Nows the perfect time to ask any questions you
  may have regarding
• MIDI
• Next class period, well discuss digital editing
  and the conversion of WAV files and/or AIFF files
  into mp3 files.