This connection is one piece that's missing in order for you to make music with your computer. While it is possible (with the right software) to play notes with your computer keyboard, most people will find it unnatural. For real music playing, you need an instrument (in MIDI terms a controller) like a piano keyboard. The instrument must be capable of MIDI output, and you'll probably need a MIDI connector and cable to plug into your sound card. That is if your sound card has MIDI capability.

The sound card is the center of the action for making music, and not all sound cards are right for the job. Some don't have a MIDI connector. Others use a type of music production based on FM (like the radio), which sounds terrible. Some don't have a MIDI synthesizer. This is the key, because MIDI transmits the notes and information about what played them separately, and a device called a synthesizer is used to create or re-create just about any kind of instrument or sound.

Synthesizers are the heart of electronic music and are much too big a subject to cover in detail here; but it's important to understand that the quality of music you get depends a great deal on the quality of the synthesizer. The early PC synthesizers recreated notes by playing modulated frequencies (the FM mentioned above) that sound about as realistic as substituting a tin bucket for tympani. Today, most sound cards use wave table technology. Instead of trying to change the shape of sound, this approach uses actual snippets of real sound, called samples, which are then interpreted and played by the synthesizer. The result can be much more realistic, but there are differences among the many available wave table (or sampling) synthesizers.

Most of the sound card synthesizers use the General MIDI (GM) standard, which defines a list of 128 sounds and instruments. A good example is the Yamaha OPL3 synthesizer that is built into about half the sound cards on the market. This has some very good reproductions of real instruments, for example, the church organ and harmonica. But it's not good for all 128 --few synthesizers are--and there are major differences among synthesizer boards in the tone and timbre of their samples. Another difference is that a few low-end sound cards have on-board RAM that allows you to download wave table sets. That way, if you don't like the guitar sounds of one set, you can shop around for better ones and substitute them. This is essentially what the pros do, but on a much grander scale.

The final element you need for MIDI music is software. There are many products, but they can be categorized like this:

1. Music generation programs. These are used to make royalty-free music for multimedia presentations and the Web because they can create music automatically (although you can change and edit what they produce). Microsoft Music Producer is an example.

2. Sequencing programs. As the name implies, these programs are used to organize and sequence music. Essentially they're music and sound editors. They are distinguished by the ability to deal with minute details in the MIDI sound environment, for example the Cakewalk Pro Audio 5.0 package ($395) supports 256 MIDI tracks and has 96 programmable faders (the jargon at this level gets very thick).

3. Composition software. Musicians trained in reading sheet music will be more at home with this type of software than with sequencers because they use traditional staff annotation for the music. Passport's Rhapsody ($179) is a good example; it supports up to 32 staves and eight voices per stave, plus conversion to and from MIDI files.

Most sound boards now ship with one or more of these types of programs, so you can at least create some music from get-go. However, as with the quality of sound boards, there are also big differences between software packages that cost less than $100 and the much more sophisticated programs that go from $199-$499. The extra money buys you greater control, more "voices" (the number of instruments that can be sequenced simultaneously), better integration with storage devices like digital tape (DAT), and often many more special effects.

Putting it all together, a MIDI music making collection includes a sound card with wave table synthesis ($99–$399), a MIDI controller ($150–$500), MIDI cables and connectors (about $50), and software ($50–$500). That means that a "middling" MIDI setup runs from $500–800. This will have enough sound quality to get you started. However, if you are serious about music and are technically inclined, it won't be long before you start searching for better gear.

It also won't take you long to discover that there is a disheartening jump from personal to professional quality MIDI equipment. For example, a true 88 key keyboard controller will cost $1,000–$2,500, a synthesizer with 32 MB of RAM that handles hundreds of samples (patches) from $750–$3,000, and a suite of software that might set you back $700.