Thứ Bảy, 4 tháng 6, 2011

Getting Your Computer “MIDI Ready”

-  PART 1 -

by Michael Tyler
Computer Music Products
If you are a musician wanting to incorporate a computer as part of your musical arsenal, you will want to become familiar with at least a few of the options available to you when setting up your computer music system. I will show you the common MIDI setups for the IBM/PC compatible computer. Part 1 of this article will cover the procedure for setting up a simple MIDI system using a MIDI compatible sound card. Part 2 will describe setting up your system with a separate, dedicated MIDI interface. As always, I hope you will find this helpful and informative!
For the purpose of this article, I will define a “MIDI setup” as a system that includes...
  • A computer equipped with music software (i.e., for recording, playback, printing, etc.)
  • A MIDI keyboard (for playing/inputting music into the computer software)
  • A MIDI sound source (MIDI keyboard with built-in sounds, or a sound card, or a sound module)
  • A means of connecting the MIDI keyboard to the computer (MIDI interface hardware and cables)
P.S. - If you haven’t already read the article entitled “Where To Begin”, you may want to read it before this particular article.

Basic Sound Card MIDI Setup
NOTE: When this article was originally written, Soundcards often included external MIDI interface support. Today, this is not as common. The easiest way to connect a MIDI keyboard to your computer now is with the use of a USB MIDI Interface. (this note was added in 2004)
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A sound card MIDI system is the simplest and most economical MIDI setup. There are a couple of typical sound card setups that will directly apply to the majority of MIDI musicians. If you own a PC of a fairly recent vintage (say, about 2 years old or less), chances are extremely good that your computer came with a pre-installed sound card. Most sound cards are SoundBlaster® compatible and will have a built-in MIDI interface that is accessible through the sound card’s gameport/joystick receptacle.
Notice that I said most will have the MIDI interface capability. It is up to you to verify whether yours has it or not, by checking the documentation that came with your particular sound card. (If there is no mention of this, then you most likely won’t be able to use the sound card for connecting your MIDI keyboard, so you will need to purchase a separate MIDI interface.) Even though your sound card may have the built-in MIDI interface, the manufacturer rarely includes the gameport-to-MIDI adapter cable necessary for actually connecting your computer to your MIDI keyboard instrument! Fortunately, these adapter cables are not costly.
12-foot gameport-to-MIDI cable adapter
 Photo of a Gameport-to-MIDI Adapter Cable
Installation of one of these gameport-to-MIDI adapters is straightforward. Just plug the 15-pin end into the gameport/joystick connector on the back of your sound card, and plug the 5-pin MIDI ends into the back of your MIDI keyboard. (The end labeled MIDI “IN” from the gameport cable plugs into the MIDI “OUT” receptacle of your keyboard. And, as you would expect, the end labeled MIDI “OUT” from the gameport cable plugs into the MIDI “IN” receptacle of your keyboard.)
The final step is to start up your music software, go into its MIDI Setup Menu, and “engage” by selecting your sound card’s MIDI input and output driver so the software knows to use it. (Your music software owner’s manual will guide you through this final step, in case you have no idea what I mean by input/output drivers!). From start to finish, this entire process should take only about 10 or 15 minutes, and you’re in business!
gameport-to-MIDI hookup

Here are two diagrams of common Sound Card MIDI Setups

Diagram 1 - Standard MIDI Keyboard hookup
Diagram 1

Diagram 2 - MIDI Controller hookup

Diagram 2
Note: The standard MIDI keyboard hookup (Diagram 1) gives you two options for playback of MIDI songfiles. You can designate in your MIDI software to trigger the sound card only, or choose to have the software send MIDI playback data to your keyboard to utilize the keyboard’s own built-in sounds. (You can usually select, from within your particular music software, whether to output the “MIDI flow” to either the sound card or the MIDI output port connected to your MIDI keyboard to trigger whichever one you want - in some cases, even both!).
In the MIDI controller hookup (Diagram 2), the keyboard controller has no sounds of its own -it is totally dependent upon the sound card for producing any sound at all. When your computer is on and your music software is running, playing the MIDI controller keyboard will trigger the sounds contained in your sound card and you hear them via the multimedia speakers connected to the sound card.

Upgraded Sound Card MIDI Setup
The next step MIDI musicians sometimes take is to upgrade their sound card-based MIDI setup. The upgrade does not change the basic hookup for MIDI input -you still use the gameport adapter for connecting your keyboard to your computer as previously described. The primary goal is to get higher quality MIDI instrument sounds than what most factory installed sound cards typically offer.
One way to upgrade your system is to add a MIDI “sound module”. A sound module is essentially a small box containing hundreds of instrument sounds and numerous drumkits to use in your MIDI recording projects. Most recording musicians will eventually add at least one or two sound modules to their desktop recording setups.
You can easily add a sound module by connecting the MIDI "OUT" from the gameport cable (shown in Diagram 2) to the MIDI "IN" of the module. (In Diagram 2, you see that the MIDI "OUT" cable is available for this purpose, since it is otherwise not being used in a soundcard-only setup.) When you play your keyboard, the sound module receives the MIDI data and triggers the sound module's built-in sounds. Likewise, when you play back a MIDI recording from your computer, the module's sounds are triggered from the gameport cable's output. Of course, you will need to connect a pair of speakers to your sound module in order to hear it when it’s being used for MIDI playback instead of your computer’s soundcard, or you can monitor the sound directly from the module by plugging in a set of headphones into the modules headphone receptacle.
MIDI Sound Module
Photo of a MIDI sound module

Conclusion for Part 1
Setting up a sound card based MIDI system is economical, simple to accomplish, and enables most anyone to get started with MIDI/music applications right away with a minimum of effort. Part 2 of this article will cover MIDI setups using dedicated MIDI interfaces for desktop and laptop computers. 

-  PART 2 -
by Michael Tyler
Computer Music Products

I explained the typical sound card/MIDI setup in Part 1 of the “Getting Your Computer MIDI Ready” article. Both articles are designed to help you as you set up your computer for MIDI music applications. Try to read the articles in order, as I tend to write each article building upon what I assume you learned in the previous one!
Dedicated MIDI Interfaces - What Are They?
Before we go on, I want to clarify the term “dedicated MIDI interface.” It simply refers to a MIDI hardware component dedicated to the primary purpose of communicating MIDI data (i.e., to and from a computer). A dedicated MIDI interface is not and does not function like a sound card (surprising how many folks think so). There are no sounds contained in a dedicated MIDI interface -- any sound produced is generated by the MIDI instrument the interface is connected to (like a MIDI keyboard or MIDI sound module, for instance).
Why Use A Dedicated MIDI Interface Instead
Of A
 Sound Card Gameport-to-MIDI Connection?
There are situations where a sound card gameport-MIDI connection just won’t do the job. Many desktop computers used to include a soundcard equipped with a 15-pin gameport. This enabled the use of a gameport adapter cable for connecting a MIDI instrument. Today, most computers no longer come equipped with such a gameport connection. The most common way to connect a MIDI keyboard to a computer nowadays, is with a USB interface. Also, laptop users need to purchase an external interface for connecting a MIDI instrument. Again, the use of a USB interface is the most common way to accomplish this.
There are single-port MIDI interfaces and multiple-port MIDI interfaces available. A common situation is when the musician who has two (or more) MIDI instruments he or she wants to connect to the computer. A special “dual” or “multi” port MIDI interface is required to connect more than one MIDI instrument. Note: Although you can “daisy-chain” 3 or 4 MIDI instruments via “MIDI THRU” ports when using a single-port MIDI interface, you will not have independent control over individual instruments connected in this way. The other problem with a daisy-chain hookup is the invitation for “MIDI log-jam” - -a condition where noticeable timing delays occur in the instruments near the end of the chain. The use of a dual, or multi-port interface will give the user total control over each instrument and virtually eliminate MIDI timing errors in a multiple instrument setup.
The Types of Dedicated MIDI Interfaces
EXTERNAL MIDI INTERFACES - First introduced primarily for laptop computer users, the external types are now just as popular with desktop users. This is mainly because of their ease of installation and portability. Many musicians, for example, work with two computer systems between home and studio. They need only purchase one external interface for the two systems, because they can easily disconnect and connect the interface to either system. Initial installation is a breeze. You just install the MIDI driver for the interface and plug the interface cable into the computer’s USB port, and you are ready to go. The illustration below is an example of an external MIDI interface that connects to your computer via a USB port.
The UNO 1x1 USB MIDI Interface
A Simple USB Single-port MIDI Interface
MIDI Sport 4x4 USB MIDI Interface4-Port USB MIDI Interface
MIDISport 8x8 USB MIDI Interface8-Port USB MIDI Interface with SMPTE Synchronization
External interfaces come as single, dual, and multi port configurations. Advanced features such as SMPTE Time Code synchronization and MIDI routing are available on top-of-the-line models. See below...

INTERNAL MIDI INTERFACES -  Most of today’s internal MIDI interfaces are integrated as a feature in the circuitry of certain digital audio cards and consumer soundcards. An internal  “MIDI interface-only” device for desktop computer systems is not as common as it once was. For the most part, internal interfaces have been discontinued in favor of external USB interfaces.

Hookup Diagrams for MIDI Interface Connection
EXTERNAL - The following diagram illustrates how an external USB interface makes the connection between a computer’s USB port to a MIDI keyboard controller. 

USB MIDI Interface Hookup
Photo of a typical USB MIDI interface Setup

INTERNAL - The following diagram shows how an internal interface is connected for a desktop computer/MIDI setup. (Internal MIDI interfaces are a rarity nowadays. Almost all MIDI interfaces are now external USB types.)

Internal interface hookup diagram
(Internal MIDI Interfaces are no longer as commonly available as they once were)

Tips for installing an internal MIDI interface - avoiding hardware conflicts:

In case you do plan to install an internal MIDI interface, there are some steps you can take to help you avoid problems. Before installation, write down all of the hardware IRQ (interrupt) and Address settings that are being used for the existing hardware already in your system. Find out the settings for your mouse, modem, sound card, printer, scanner, etc. and write them down! Keep this list with you as you begin installation of your MIDI interface. I keep a list of all my hardware settings on a 3" X 5" card and tape it to the side of each one of my computers. That way I can glance at my list and know what resources (IRQ’s, DMA channels, and Addresses) are already in use, so I’m not as likely to cause a conflict for new hardware I may install later.

Do you have only one MIDI instrument you will need to connect?You can use either an internal or external single port MIDI interface. A “single port” means you have ONE MIDI Input and ONE MIDI Output connection.
Do you want your interface to be portable between two or more computers, or are you using a laptop computer?For portability and/or laptop computer use, a USB interface is a simple solution. Single, dual, and multi port versions are available. “Dual port” means you have TWO MIDI Inputs and TWO MIDI Outputs. “Multi port” means THREE (or more) MIDI Inputs and THREE (or more) MIDI Outputs
Do you have two MIDI instruments you want to connect to the computer?Choose a dual port or multi port interface. Choose a multi-port interface if you think you will need to add more than two MIDI instruments to your computer music system in the future.
Deciding which MIDI interface to purchase for your system is an important step, so you’ll want to make the right decision. Don’t let the number of choices cloud the issue, however. You can easily zero-in on the interface that is just right for you, simply by considering your personal requirements.