Burning Question: Do A/V Cables Matter?

More Wired outtakes -- this one from the Test special issue of October. Imagine how thick the magazine would be if they publisehd all the articles they comissioned...

After shelling out for a TV, DVD player, amplifier, and speakers, you still need a mess of cables to hook them together. And that can get expensive. "Cables are considered accessories, and they have a high markup," said Rich Sulin, who heads audio/video equipment testing for Consumer Reports.

Take for example the HDMI cable that carries digital video and audio signals to a television. A one-meter length from Monster Cable retails for $200 -- as much as a high-quality DVD player.

Is a wire really worth that much? The experts we talked to emphatically said "No!"

That's especially true for digital cables. "As soon as it's digital, you buy the cheaper one," said Pavel Zivny, a product engineer at Tektronix who designs oscilloscopes for testing high-frequency signaling equipment.

The beauty of digital signals is their resiliency. Analog cables carry precise signal values, and the slightest degradation changes the information -- possibly resulting in blurriness on TV screens or messed-up notes in speakers. Digital carries only two pieces of information -- ones and zeros. The signal can take a pretty good beating, but the device at the other end can still easily tell the difference. And there are no gray areas between a good and bad digital connection. "You either are getting information and it works fine, or it is broken," said Zivny.

So for a high-quality, low-cost connection, go digital. Depending on your specific equipment, that means HDMI or DVI cables for video gear and optical or digital coaxial cables for audio components. To find bargains, Rich Sulin recommends skipping over big-name cable displays in the front of an electronics store and looking in the back where the cheap brands are hidden. You can also find deals online from companies at sites like Amazon.com.

If you can't afford to upgrade your components to digital, you shouldn't be blowing cash on fancy analog cables, either. Fortunately, though analog cables vary in quality, the differences are not huge. Pavel Zivny recommends basic guidelines for buying a decent analog cable. Look for one with a thick plastic or rubber coating that prevents it from easily crimping, since that can distort the signal. And if you can find information about the metal shielding inside the cable, look for one with a tightly woven, braided layer. A double layer is especially good.

One component that must have an analog connection is the speaker. And you can really save money on these cables. "As long as they're low enough resistance, you'll be fine," said Rich Sulin. That simply means getting thick copper wires that let the signals travel unimpeded.

For buying speaker wire, Sulin and Zivny recommend bypassing the home-theater and electronics shops and heading to stores like Home Depot where you can cut the length of double-strand cable you need from big spools. The thickness, or gauge, of copper you need depends on the length of the cable running to each speaker. According to Zivny's calculations, a 15-foot cable run requires 14-gauge wire, a 25-foot run requires 12 gauge, and 40 feet requires 10 guage. Remember: Smaller gauge numbers correspond to thicker wires.