By Lou Dolinar
Third in a series
Updated Feb. 14, 2006

Love your iPod? Spend a lot of time listening to music in front of your PC? Maybe its time to move your music collection into the living room.

In the past two columns, we explained how to clean up the stuttering and dropouts common in PC-based audio. This week we'll look at some of the ways you can play computer-stored music on conventional home entertainment setups.

Music from your computer starts out in the digital domain, where it is relatively immune from noise, distortion and other forms of electronic grunge. Sound, however, is an analog phenomenon, and what you actually hear from your speakers, in principle is no different than what you'd hear from an old-fashioned hand-cranked Victrola. Somewhere in between the computer and the speaker, a digital-analog converter makes the change.

Where this transition takes place can have a huge impact on sound quality, because analog signals are inherently more susceptible to electronic grunge. The least preferred method is the most common: Your computer's sound card contains a DAC, and you plug your computer speakers, which contain built-in amplifiers, into the card.

PCs generate a lot of noise that other electronic devices can pick up - that's why they are externally shielded and have to be certified by the Federal Communications Commission. Your sound card's analog circuitry is inside that mess, however, and invariably picks up some of it. You don't hear it, generally, because those computer speakers are low-fi; switch these outputs to a decent receiver/surround speaker and you'll be greatly disappointed.

So what's the solution? If we move the conversion process outside the case, away from the computer, we get rid of a lot of noise. Virtually all sound cards, and many motherboards, incorporate a digital-out for music, either optical cable or preferably coaxial S/ PDIF or Sony/Phillips Digital Interface, a single cable that carries stereo or surround sound data in digital form. Since most home entertainment systems incorporate DACs and accept coaxial S/PDIF inputs, you can connect them directly with the sound card and hear a major improvement in your music - particularly if you have a decent set of speakers to go with the amplifier. Your computer speakers, meanwhile, stay connected to the analog output.

About the only problem with this scheme is that home entertainment systems rarely live next door to home computers. S/ PDIF coaxial cables, fortunately, can be run at least 15 meters (49 feet), and sometimes as far as 25 (82 feet). Suppliers for high- quality custom lengths include www.bluejeanscable.com; www.heartlandcables.com and www.signalcable.com.

A 60-foot (18 meters) cable costs $39.50 at Blue Jeans Cable. Note that while you can use regular RCA analog interconnects in a pinch, you do need cable rated specifically for digital signals if you want the best quality here.

Avoiding internal computer noise has made so-called external sound cards increasingly popular. These are even quieter than S/ PDIFs. They take the entire sound card function and move it outside the computer case, into its own box, with its own power supply; data travels to the box via USB2 or Firewire cable.

Besides isolating the conversion process from noise, these units, which were pioneered by studio musicians and DJs, also have room for convenient access to scads of external connections, and work nicely with portable computers.

The ubiquitous Sound Blaster line includes the Audigy 2 NX in this genre, which, at less than $100 retail, is excellent for surround sound gaming .

Audiophiles tend to prefer somewhat pricier gear such as the M- Audio Audiophile USB ($179) or the Edirol UA-3FX USB, also $179. You might want to check out the new PC Audio Forum at www.audioasylum.com for comments on these devices, along with suggestions for tweaking them.

Whichever route you go, dig up the documentation on your sound card and receiver before you try to change the connections.

The sound card may require you to alter software settings to activate the S/PDIF and you'll have other settings to fiddle with on the amplifier end. The manuals are rarely transparent: I've wasted hours trying to get setups to work, since it's a sort of chicken and egg situation: You can't fool with the amplifier to get playback until you have a digital signal from the sound card, and you can't tell if you have a digital signal from the sound card until you have the amp set up correctly.

All these devices share one disadvantage, however - you need to run software and control the whole operation from your PC.

PERSONAL TECHNOLOGY, If music matters, link outside the box

[NASSAU AND SUFFOLK Edition]

Newsday - Long Island, N.Y.

Author: Lou Dolinar

Date: Feb 21, 2005

Start Page: A.28

Edition: Combined editions

Section: BUSINESS & TECHNOLOGY

Text Word Count: 788

Document Text

(Copyright Newsday Inc., 2005)