Before you buy speaker wires for your audio system, find the best speaker wires for your system. Then, buy wires that deliver the best quality, performance, and price. Here's what you need to know about the material, thickness, and length of speaker wires to make the best decision.

Wire Attributes Affecting Quality

Speaker wires facilitate the flow of electrical impulses between a receiver and a speaker. Like any wire, its thickness (or gauge), its overall length, and its constituent materials perform differently under electrical load.

The three major considerations are:

• Capacitance: The higher the capacitance, the more charge that a material (like a wire) holds at a given voltage.
• Inductance: The change in voltage that arises from changes in current. For speaker wires, the level of inductance is negligible.
• Resistance: The amount of energy that gets lost in transmission owing to the medium of that transmission. The lower the resistance, the more power that makes it to the speaker.

Likewise, a wire's performance is affected by:

• Gauge: Thicker wires (i.e., wires with lower gauge ratings) demonstrate less resistance. However, for most residential setups, an ordinary wire is fine. Unless you're running hundreds of feet of wire or have super-premium speaker hardware, a regular 16-gauge wire is fine.
• Length: Longer wire runs increase resistance.
• Composition: Different metal types conduct electricity in different ways. Copper is cheap and features low inherent resistance, but is susceptible to corrosion if it's exposed to air. Silver demonstrates even lower resistance but the price point relative to copper is not favorable. Gold won't oxidize on contact with air (so it's a great plug material) but it's more resistant than either copper or silver so it's not ideal for cable runs.

When Quality Affects Audio Performance

Assume that you're dealing with a pure wire and not a hybridized wire that features its own built-in filters at the plugs. With a pure wire, you won't notice a decline in audio quality until the resistance of the wire differs from the speaker's impedance by more than 5 percent.

A speaker's impedance is a measure of the amount of resistance the speaker offers to the current flowing from the input wire. Speakers are identified by an impedance rating measured in ohms. You'll encounter 2-ohm, 4-ohm, 8-ohm, 16-ohm, or 32-ohm speakers in the audio market, although the rating need not be a power of 2.

Wires offer an effective load at a given combination of material, length, and gauge. For example, a 4-ohm speaker works with a 16-gauge copper wire for lengths up to roughly 24 feet. Beyond that, the speaker's performance degrades. You won't necessarily hear the degradation immediately — a wire at 30 feet may not sound different to you — but over longer runs, you may notice it.

Avoid runs of more than 50 feet to reduce the risk of high-frequency attenuation, even if the theoretical length of the wire is within tolerance.