MIDI was once reserved for digital synthesizers, samplers, sequencers and sound modules. If you wanted to send MIDI to a device beyond your controller, you would need a sound module or some similar device capable of functioning as a sound module. But with today's technology, you can use your computer as a sound module.
Digital recording software is big business, and it enables you to record music right on your PC using MIDI notation. But not all recording programs are MIDI-enabled. For example, though very useful for analog recording, Audacity is useless when it comes to MIDI. Here are some of the best and most popular MIDI-friendly digital recording programs.
LOGIC PRO: In the interest of full disclosure, I want to state that I'm extremely biased in this regard, because I've personally used Logic Pro for years and have almost no complaints about it. Logic gets my #1 vote because of the power and versatility of its software synthesizers, like the ES2 and the EFM1. The Logic softsynths are so clean-sounding and powerful, they almost completely negate the need for hardware synthesizers altogether. Even synth legend Vince Clarke has used Logic softsynths in his Erasure recordings.
CUBASE: Like Logic, Cubase offers its users fully customizable software-synthesizers like the HALion Sonic SE and the Prologue. Maintain full control every parameter, or just tweak with the presets. You can easily integrate your MIDI keyboard or other controller device, and then capture the softsynth sounds perfectly using Cubase's multitrack recording environment.
REASON: Reason isn't one of my favorite programs when it comes to recording, but its software synthesizers are extremely impressive. The Subtractor Analogue Synthesizer, in particular, is worth the price of the software. You can also explore the Thor Polysonic Synthesizer and the Malstrom Graintable Synthesizer (an especially unique softsynth).
GARAGEBAND: The GarageBand software instruments are really nothing to write home about, but for beginners who just want to get their feet wet with MIDI, GarageBand is a worthwhile choice. You can easily connect your MIDI keyboard, select instrument sounds and edit parameters without any formal knowledge of electronic synthesis. While the aforementioned programs are geared toward advanced users who like to maintain full control of their cutoff, attack and other features, GarageBand is very straightforward. GarageBand is also a Mac-only program. Windows users might try MixCraft, which is similarly geared toward beginners.