What is a soundfont?
Friday, March 30, 2007
By Stephane Brault
You probably already know what a text font is. It is used to change the appearance of the characters you type in programs such as Microsoft Word. Well you can think of a soundfont in a similar way : it is used to change the sound of a MIDI instrument with a sampled instrument. So instead of hearing the crappy General MIDI sound in your favorite MIDI song, you can replace it with an instrument you sampled yourself. So a soundfont defines sound rather than shapes.
SoundFont is a brand name that refers to a file format and associated technology to fill the gap between recorded and synthesized audio, mainly for the purpose of computer music composition. SoundFont is a registered trademark of E-mu Systems, Inc.
You've heard MIDI files before. Depending on your soundcard or speaker setup, they can sound anything from bearable to ethereal unlike WAV files which are more predictable. The reason behind this is that WAV files contain actual digital recordings whereas MIDI files are basically music notations which your sound card interprets and plays. They are different types of sound cards, which explains why MIDI files sometimes sound great and sometimes sound awful.
All the notes are interpreted using a table of recorded or synthesized sounds sampled in a special area of your sound card. There was a time when you simply couldn't change these sampled sounds. SoundFont technology enables you to change these samples, giving more control to software rather than hardware.
A soundfont file, or soundfont bank, contains one or more sampled audio waveforms, which can be re-synthesized at different pitches and dynamic levels. Each sampled waveform may be associated with one or more ranges of pitches and dynamics. Generally speaking, the quality of a SoundFont bank is a function of the quality of the digital samples and the intelligent association of samples with their appropriate pitch ranges. Quality is also dependent on the number of samples taken for a given range of pitches.
SoundFont banks are tightly integrated with MIDI devices and can be seamlessly used in place of GM patches in many computer music sequencers. The sound quality of SoundFont banks is generally regarded as superior to standard GM banks, and many SoundFont banks have been created specifically to replace GM banks with samples of each corresponding instrument.
Can I use soundfonts on my computer?
In order to use soundfonts, you will need a sound card capable of storing and playing soundfonts. Most soundcard from Creative Labs are able to handle soundfonts. The PCI-based Sound Blaster Live! and USB Sound Blaster Extigy and Audigy 2 NX audio cards are all SoundFont 2.0 compatible. The PCI-based Sound Blaster Audigy series along with the PCMCIA-based Audigy 2 ZS Notebook are SoundFont 2.1 compatible. Unfortunately, most cheap motherboard-integrated sound card are not soundfont-compatible.
System memory is used to store soundfonts as they are not stored on you sound card. Therefore, a large amount of memory (RAM) is recommended. Soundfonts file size can vary from 100Kb to 200Mb (or even more) so depending on your OS needs and the soundfonts you are using, you may need to add RAM to your computer. A 200Mb soundfont will use 200Mb of RAM.