Computer Audio Comes of Age
Editorial by Tom White
Even in the era of "moving pictures" the pioneers of modern entertainment recognized the importance of providing high-quality audio to enhance the video experience. Before the "talking pictures", the theater organist provided musical accompaniment. With talkies came dialogue and sound effects. Today, movie sound tracks are the state of the art for the entertainment business, demanding the best composers and using innovative technologies such as "surround sound" and multi-channel all-digital playback.
In sharp contrast, computer-based entertainment is just now coming out of the dark ages as far as sound is concerned. The majority of today's "multimedia" computing systems do not offer state-of-the-art audio performance, relying instead on commonly available but inferior technologies for generating sound. The result is that content developers are unable to produce compelling and realistic sound tracks for their titles.
Part of the problem lies with a technology called "FM synthesis". In playback of music, synthesis allows for creation of many different sounds which are not otherwise available. For example, with a synthesizer it is possible to imitate the sound of a Grand Piano without ever having the piano at your touch. But FM synthesis is only one method of generating sounds, and is not a particularly realistic method. In fact, though developed for professional musical instruments, FM synthesis is largely obsolete in that market today.
The best quality commonly available today happens to be the most obvious: recording the actual instruments and storing them for playback. This technique is typically called "wavetable synthesis", and requires both a wavetable synthesizer and a library of sound "samples" from which to create required sounds. Data compression schemes and advances in silicon design have dramatically reduced the cost of wavetable synthesizers, making them viable for the PC market.
Though the quality of realism and clarity will vary among manufacturers, a good wavetable synthesizer can produce music which is indistinguishable from a music recording made using real instruments. Wavetable synthesis also provides an opportunity for a larger variety of sounds, since any sound can be made available simply by providing "samples", unlike FM which can only create certain types of sounds based on the physical acoustics of FM sound modeling. As a testament to the superiority of wavetable, virtually all game music composers create their sound tracks on a wavetable synthesizer to realize the fullest sound, and subsequently edit them for playback on lesser FM synthesizers.
Oddly, while the PC market rapidly consumes all increases in CPU and graphics performance, FM synthesis continues to be sold despite the availability of better, cost effective, solutions. The reason FM has been able to hang on so long has little to do with technology (or sound) and everything to do with market conditions. For a long time FM was the only synthesis technology available at the right price point for PC audio, making FM a defacto standard for developers.
Then, in 1991, the MMA (MIDI Manufacturers Association) created "General MIDI", a specification which provides a standardized design for music synthesizers and opened up the PC to better synthesis technology. With General MIDI there is no dependence on FM synthesis, and developers are now able to create music that actually sounds as it was intended.
As the market for multimedia computers matures, consumers will look for even more rewarding applications and better ways to make use of their investment. Thanks to wavetable synthesis, they have an entire orchestra at their finger tips, and are able to embark on adventures in learning or creating music, as well as hear full cinematic scores with their favorite games. Better sound, more variety, and better applications have made wavetable a necessity in multimedia PCs, ending the reign of FM.
- Tom White
This editorial was written for Electronic Buyers News in 1996.
Tom White is President & CEO of the MIDI Manufacturers Association (MMA) and a consultant on multimedia technology and marketing, specializing on the convergence of the computer and music industries. Tom also sits on the Steering Committee of the Interactive Audio Special Interest Group, which is developing recommended practices for new audio technologies in multimedia.