| IMPORTANT NOTE: These instructions apply only to the MIDI mapper in Microsoft Windows 3.1. The ability to modify the MIDI settings was, unfortunately, left out of Windows 95 and 98. |
The MIDI mapper in Microsoft Windows allows you to customize Windows to work with your particular MIDI hardware and software. It functions much like the Windows printer and video drivers -- once they are correctly configured, you can use any Windows program with these devices.
The MIDI Mapper remaps patches, notes, and channels, and adjusts velocities. It uses the Patch Map, Key Map and Setup to determine how to do this.
Until recently, there wasn't any standard for patch or note numbers. Now there is the General MIDI specification, an official specification published by the International MIDI Association. This standard does identify which instrument is to be used for each patch number. However, there are a large number of MIDI sound files in circulation which do not follow the General MIDI specification. Playing these through a General MIDI device can make them sound pretty bad.
Microsoft Corporation has produced their own version of the General MIDI specification, complicating things somewhat. The Microsoft standards require less of the equipment than the General MIDI standard. General MIDI supports 32 notes sounding at the same time on all 16 MIDI channels. Microsoft has defined two less capable devices -- a "basic" device and an "extended" one.
Basic Device
A Basic device must be capable of playing 6 notes, in at least 3 different instruments, as well as 5 percussion notes. All sound cards, including the original 8-bit sound cards, can do this. Basic devices play the melodic instruments on channels 13 through 15, with the drums on channel 16.
Extended Device
Extended devices must be capable of 16 melodic notes, using 9 instruments, plus 16 notes on 8 percussive instruments. Extended devices use channels 1 through 9 for melodic sounds, with the drum track on channel 10.
Microsoft's Authoring Guidelines
These guidelines provide for producing MIDI files that can play on any system by putting 2 copies of the song in each file -- both a basic and an extended version. Each must meet the rules for its particular type, including placing the higher priority sounds on lower numbered channels.
To prepare for playing MIDI files under Windows, first install the drivers that came with the sound card. These are usually installed automatically by the software setup program, or they can be installed manually in the Control Panel.
Most sound cards also come with their own setups for the MIDI Mapper. These are typically labelled something like Basic, Extended, and All. The principal differences between them are the channels used. Note that for some cards the output for one of the drivers will go to the FM Synthesizer (which is on the sound card), while the output in another driver will go to the external MIDI device. If you are using only the sound card, you will have to edit the maps to direct all of the output to the FM Synthesizer.
The All map is recommended for listening to the MIDI files in the Gilbert and Sullivan Archive, and for listening to most downloaded MIDI files. This map listens to all 16 MIDI channels. This is important, as not all MIDI files follow either the General MIDI or the Microsoft specifications. The All map will catch all of the instruments regardless of the combination of channels used.
If you do not have a map that watches all 16 channels, create one which sends the output of all channels to the FM Synthesizer.
The current version of Netscape includes a built-in MIDI player. When using Netscape, click on the MIDI file link with the left mouse button to play the file, and with the right mouse button to download the file to your computer.
Updated 14 December 1999