by David Hakala
While every computer comes with sound capabilities built into its motherboard, they’re usually of mediocre quality. Discriminating users want more so they buy add-on sound cards. The features you need in a sound card depend on the type of listening that you do most.
Some people use sound cards mainly for music and DVD playback. Others want the full sound effects of computer games. A few create sound files for business or personal use, and they have specialized needs in a sound card.
PC gamers should check to see that a sound card supports DirectX, the Microsoft Windows technology most widely used to accelerate game action and convey bone-shaking, ear-splitting sound. Ask what version of DirectX the card supports and how the card can be upgraded to support future versions.
Many PC games are written for EAX technology, used in high-end Soundblaster cards made by Creative Labs. EAX enables 3D environmental surround-sound. You need a 5.1 channel speaker system or a 2 or 4 channel system that emulates surround-sound to take advantage of EAX.
If music is your PC passion, focus on Dolby Digital 5.1 support. Again, the better your speaker system the better you can take advantage of this feature. Audiophiles will also want to ask about the signal-to-noise and THD (Total Harmonic Distortion) ratings of sound cards. The higher the signal-to-noise ratio, the better the sound quality; most sound cards fall in the range of 80 to 105 decibels. Conversely, the lower the THD, the better the sound quality. You’ll see anywhere from 0.1% to 0.005% THD.
If you create music or other sounds, you need to consider a card with Wave Table Synthesis support. It is a method of using sound samples to mimic instruments.
For any sound card, the “bit rate” is the most important quality factor. A 24-bit card sounds much better than an 8-bit card because the card can process data faster and more efficiently. You will also want to get as much RAM on the sound card as you can afford. Just as with a computer, more RAM on a sound card means more efficient processing
David Hakala has perpetrated technology tutorials since 1988 in addition to committing tech journalism, documentation, Web sites, marketing collateral, and profitable prose in general. His complete rap sheet can be seen at http://www.linkedin.com/in/dhakala