Amiga Collections: MegaDisc/MegaDisc 07 (1988)(MegaDisc Digital Publishing)(AU)[WB].zip/MegaDisc 07 (1988)(MegaDisc Digital Publishing)(AU)[WB].adf/MUSIC/About_MIDI

Text File | 2000-04-10 | 11KB | 198 lines

                     AMIGA MUSIC AND THE MIDI INTERFACE

                                            by Doug Myers.

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 ED: This is the first in a series of articles about Music for the Amiga
     by Doug, who is a professional in this area.

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     Why did you buy your Amiga?

 Most of us use our computers for the tasks which we decided they would be
 best suited when we bought them. Very few of us have the time or
 opportunity to look at the many other things our computer  might be able
 to do if we had the inclination and the money. Those of us who are
 involved in Word Processing are probably quite happy to play a few games
 on the side but do not have the interest or money to set our Amiga up for
 video work or for many of the other possibilities.

 In this article I will discuss a few of the salient facts involved in
 sound reproduction with the Amiga but will especially look at the use of
 a MIDI interface for making music.

 That the Amiga is a much more capable machine for making sounds than other
 micros is quite evident to the user when he first runs his Basic
 demonstrations and has the machine talking to him. The use of the Paula
 chip has put the Amiga far ahead of other micros in sound reproduction
 but the use of filters to restrict the frequency range of Paula does not
 help the fidelity of what one can do.  In a later article I will deal
 with this problem and how it can be overcome in each Amiga. Commodore
 has twice taken the lead in this field.  The sound chip in the C64 is
 also far ahead of other computers.  This basically means that the Amiga,
 like the C64 before it,  can play music which is good to listen to if it
 is hooked into your home stereo. Other computers are usually equipped
 with "beepers" and cannot reproduce music at a level which would be
 satisfactory to a discerning listener.

 This problem has been overcome by the introduction of what is now a music
 industry standard - the MIDI Interface. The MIDI or Musical Instrument
 Digital Interface was developed to allow synthesizers and drum machines
 of different makes to "talk" to each other. It was not long after it had
 been developed that its use in connecting musical instruments to the
 micro computer was also being investigated. This extension of the use
 of digital communication was an obvious one.  The use of the interface
 with computers nevertheless demanded new software programmes which could
 use these possibilities and channel them for use by the serious musician.

 The big advantage of MIDI with any micro computer is that it allows the
 user to use the professional sounds from  synthesizers  or drum machines
 or both in the finished musical product. The final sound will no longer
 depend on the computer but will now be dependent on the quality of the
 associated musical hardware. This means that computer generated music is
 good enough to be used in the music profession and this is by now usual
 in most fields of music production. It follows that if you are willing
 to add the right sort of hardware to your computer you can produce
 professional sounding music at home. This is a big leap forward from
 Irving Berlin's piano which could have its key changes manipulated by
 a lever!

 MIDI allows for the connection of hardware using normal 5 pin din
 connectors of the type favoured in Europe. A MIDI cable consists of two
 din connectors with cable joining all five pins although only three of
 the pins are used. Such cables are used to patch the system together.
 MIDI interfaces have female din plugs labelled "IN","OUT" and "THRU".
 The rule is simple.  IN  goes to OUT and vice versa. THRU is used when
 you are connecting to a  number of instruments in the chain.

 MIDI allows for 16 channels of communication and it is therefore
 necessary to set the receiving instrument to the allocated channel
 before it can pick up the information being transmitted. The amount
 and types of data which can be transmitted makes MIDI an extremely
 powerful tool. The way in which a keyboard is played is remembered
 precisely through MIDI.  Touch sensitivity, use of pedal, pitch bend,
 length of note and volume are all recorded faithfully and can be
 played back at will.

 The world of digital music making and recording moves on apace and while
 it is still a bit on the expensive side for the home enthusiast it is
 not altogether out of reach. What is needed is a Synthesizer ( a
 musical instrument which can make its own sounds, which can later be
 stored and replayed). This instrument usually comes with a keyboard
 attached but once you have one you might like to go for a "Voice Module"
 which will produce a number of different voices which are already stored
 without a keyboard. This is usually much cheaper than the synthesizer
 from which it sprang. Synthesizers are also limited in the number of
 voices which they can play at one time while a  voice module can
 probably give eight voices. It is possible to mix a number of
 synthesizers together in a MIDI setup and have them playing their voices
 together or separately as one wishes.

 Next comes the DRUM MACHINE which has a number of pre-recorded
 percussion sounds which can be recorded in set patterns so that the
 percussion accompaniment to a piece of music can be fixed as part of
 the composition. The trick with using a drum machine is to make sure
 that you never progamme anything on it which could not be played by a
 drummer. The possibility of playing drum parts  will lead it to sound
 natural. A drummer is the best person to programme a drum machine.

 The third piece of equipment necessary is called a SEQUENCER. This is
 basically a digital multi-track recording studio. It allows for the
 recording of music on a number of tracks and any combination of tracks
 can be used in playback.  Merging of tracks is also possible with the
 added advantage that tracks can be "un-merged" and even a note in a
 track can be re-adjusted after recording. None of this is possible with
 analogue recording (your tape recorder). There are usually two modes of
 inputting into a sequencer.  The first is "real time" and the music is
 played in from a keyboard and plays back exactly as it sounded.  The
 second is called "step time" and here every note is entered individually
 and each note value is set for each note. This allows accurate entry of
 music by non-keyboard players. ( A further development in this field is
 the introduction of MIDI for Guitar and wind and brass MIDIs to allow
 players of these instruments to work more easily with digital recording.)

 A further extension of the digital recording field is called SAMPLING or
 "AUDIO DIGITISING". This is simply the recording of a simple sound or a
 passage of sound which can then be manipulated from your synthesizer
 keyboard. Sounds thus recorded can be manipulated in many ways i.e.
 reversed, speeded up or slowed down; parts of the sound can be islolated
 and used. Sources are live sounds recorded through a microphone and
 sounds taken from other recordings, especially compact disks.

 Your Amiga is capable of being all of the above machines if it is given
 the right software and hardware. In fact it would be perfectly feasible
 to link four or more computers together and never buy any of the music
 hardware necessary. This rarely happens as professional production teams
 have their favourite sounds and like to use the latest technology.  In a
 world which changes as quickly as the synthesizer world this means
 updating your equipment  every couple of months.(Watch the Trading Post
 for those just-out-of-favour Synths!)

 I will be reviewing some of the programmes for Amiga which deal with
 specific areas in later issues of MEGADISC. If you want to experiment a
 little try SYNTHIA as a Synthesizer emulator and DYNAMIC DRUMS as a drum
 machine. [Ed: you can get a demo of Synthia from the MD PD library.]

 The most powerful use of your computer in this area is to use it in
 sequencing and sampling. In sequencing your computer makes it possible
 to give a readout of the music on the screen as it is being played in
 and the Amiga's mouse makes the inputting of music  in step time really
 easy. It is also easy to edit music if it is on the screen in front of
 you and the final advantage is one which only your computer can offer.
 Once the music has been written it can be printed! If your Amiga is
 hooked up to a laser printer, score and parts are available in
 professional form at the moment the composition is complete.

 In the sampling/audio digitising area the computer will give you a
 waveform picture and allow you to edit that waveform and you can see
 what is happening on the screen. Most samplers do not go this far.

 A further use of your Amiga is as an editor for sounds on the various
 synthesizers you are using. Many different styles of synthesis are now
 used but they can all be edited in the old analogue mode with the use
 of editors.  This makes your Amiga an invaluable tool in creating new
 sounds. Editing programmes for the most popular synthesizers are readily
 available.

 One of the problems with a relative newcomer to the scene of
 micro-computing like the Amiga is the lack of software programmes.  While
 there seem to be many graphics software packages developed especially
 for the machine this is not the case in music.  Most of the packages are
 re-written programmes  from other computers. Now that the Amiga is
 established in the European and American markets there is just beginning
 to be some interest in music programmes and in coming issues of Megadisc
 I hope to review some of these.

 In conclusion I will list some of the most common peripherals in use in
 the industry.
 Synthesizers:  Yamaha DX series. Roland D and JX series. Casio CZ series.

 Voice Modules: Yamaha FB01, Roland MT32.

 Drum Machines: Cheapest and best for beginners is the Roland 505.

 Sequencers: Roland MC500 and MC300

 Amongst Amiga programmes Deluxe Music Construction Set is a MIDI
 compatible programme which has been around for a while. Another which
 is much more difficult to use is ProMidi Studio (Soundscape). This is
 a sequencing programme.

 In my next article I hope to give an updated MIDI circuit for the
 500 and 2000 machines and some information on the availability of
 ready-made MIDIs for the Amiga at reasonable prices.If you are building
 Steve Wright's Midi circuit from Megadisc 4 it connects to the serial
 port. The hard part to buy is the opto isolator which cost me $13 in
 Melbourne when I at last found one.

 Until the next time, enjoy your music.

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