Adding Audio

Windows XP's Media Player rocks 'n' rolls, but it doesn't do much unless your PC can play the tunes.

Choosing a sound card

A computer that can input and output sound has any number of interesting uses, such as

• Playing CDs and DVDs
• Recording and playing back music with Windows Media Player or other applications
• Recording, editing, and viewing movies with Windows Movie Maker or other applications
• Gaming
• Internet telephony (making telephone calls through the Internet) and teleconferencing
• Voice recognition (converting speech into text, as input to a wordprocessing application, for example)
• Composing electronic music

Many modern computers have sound hardware built into the motherboard. If your computer does not - or if the sound support on your motherboard makes Norah Jones sound like Fritz the Cat - you can add a sound card to bring your ears into the 22nd century. Here's what to look for:

• 5.1 channel surround sound. If you commonly play games that leave you on the edge of your seat, and you want to occasionally fall off your seat, go for 7.1 surround sound.
• For watching movies, get Dolby and THX certification.
• Full Windows Media 9 or 10 (or later) support.

The inside of a computer is a difficult place to process audio signals because it is awash with all sorts of electromagnetic signals. A sound card needs good shielding to avoid picking up noise. The card's signal to noise ratio (SNR) measures its noise immunity. An SNR of 70 dB is so-so. An SNR of 90 dB is quite good, and 100+ isn't, uh, unheard of.

When you price this stuff, remember that you're going to need good (if not particularly expensive) speakers, a subwoofer, possibly a control center, remote, and anything else that curls your toes. This stuff ain't cheap. So make sure you know what you're buying into when you get a good audio card. That said, even a cheap audio card from a major manufacturer can give you outstanding sound - much more than your current speakers can handle, guaranteed.

Voice recognition is a particularly demanding application. If you plan to use this type of software, you need a decent sound card and an excellent microphone. See the "Choosing a microphone" section, later in this tutorial.

MIDI sound generation (a technology developed for synthesizing electronic music) used to be a big deal because many games used it to generate sound. Today, with CD-ROMs and big hard drives universally available, most games produce sound directly from digital soundtracks. MIDI is important only if you want to compose electronic music on your computer. In that case, look for a card with a large number of voices; that is, a card that can generate a large number of different sounds at the same time.