Buzz
Gold-plated connectors are believed to improve your music's sound quality. But is that really the case?
© iStockphoto/alptraumWhen you step into an electronics store, the cable section could easily be called the 'wall of confusion.' There are countless types of audio/video cables—some for stereos, others for home theaters, some for HDTVs, and many that leave you wondering, 'What are these even for?' Even if you manage to find the cable you need, you're then faced with the dilemma of choosing between overpriced options and those that seem too cheap to trust.
Then, there's the salesperson. 'Have you considered silver-plated connectors?' What does that even mean? 'If you're buying speaker wire, don't forget these stands that prevent the wire from touching the floor.' Why? 'The more expensive the cable, the better the sound.' Is that true?
In this article, we’ll get straight to the point. We’ll explain, in simple terms, what each type of audio/video cable does and where it's best used. Along the way, we’ll debunk some common myths, starting with the idea that the most expensive cable is always the best.
What is a cable?
Cables are designed to transmit audio or video signals from one device to another. They carry signals between DVD players and TVs, stereo receivers and speakers, as well as computers and projectors. Cables don't alter the audio or video signals in any way. They don’t convert or process the signals—this is the job of the devices at either end. The cable is simply the messenger.
Cables are composed of three basic parts: conductor, shielding, and connector [source: Graves]. The conductor is the wire that actually transmits the signal. Several layers of shielding protect the wire from picking up radio frequency interference (RFI) and electromagnetic interference (EMI) [source: Graves]. The connector is the plug at the end of the cable that connects to your device.
Cables play a vital role in any home stereo or home theater system. If you don’t use the right cables for the right task, you might end up with poor sound or picture quality. Using damaged or low-quality cables can lead to a terrible experience. For audiophiles, using cheap cables with a $5,000 plasma HDTV is like putting low-quality tires on a Ferrari.
Some audio/video experts suggest that consumers should allocate 20 percent of their total system budget to cables alone [source: Rushing]. However, many budget-friendly cables provide a listening/viewing experience that is virtually indistinguishable from the premium options [source: Rothman].
To make things easier, we’re going to classify the vast variety of cable types into three simple categories: audio-only cables, video-only cables, and audio/video cables that carry both sound and image.
Can a group of blindfolded audiophiles distinguish between music played through a $125 pair of Monster audio cables and the same music played through twisted coat hangers? According to one informal test, the answer is no. The Consumerist shared the results of a study posted on an audiophile message board, where five audio enthusiasts were tested. All of them claimed that both the expensive Monster Cables and the cheap coat hangers sounded equally 'excellent' [source: Popken].
Audio Cables
Analog RCA cables feature color-coded connectors: red for the right stereo channel and white or black for the left.
© iStockphoto/MartinDegryseLet's begin with audio-only cables. The most common ones are analog RCA cables, which typically have red and white (or sometimes red and black) connectors. RCA cables are frequently used to connect devices such as VCRs and DVD players to TVs, or CD players to stereo receivers. These cables come in pairs, each with a red connector for the right stereo channel and a white (or black) one for the left. Often, they’re bundled with video cables. For extra protection against corrosion, especially in humid areas, experts recommend using gold-plated RCA connectors [source: Graves].
Another common audio cable type is speaker wire. This wire runs from a stereo receiver to every speaker, excluding the subwoofer, which needs a coaxial cable. Each speaker requires its own dedicated wire, which not only carries audio signals but also delivers power.
Speaker wire is typically made from 99 percent oxygen-free copper and is usually 'unshielded,' meaning the copper conductor is visible. It comes in various thicknesses or gauges, ranging from 12 to 18 (from thickest to thinnest). As a general guideline, the longer the speaker wire, the thicker the gauge should be. For lengths up to 20 feet (6.1 meters), 14-gauge wire works well, while anything over 60 feet (18.3 meters) requires 12-gauge wire [source: ecoustics.com].
Speaker wire is quite straightforward, so you can often opt for inexpensive bulk wire. And don't fall for the myth that all the speaker wires in your system must be the same length. That's not true [source: Cobalt Cable].
Most audio recordings today are digital, and several newer cables are designed to carry high-bandwidth digital audio signals. The Optical digital cable (also known as fiber-optic or Toslink) transmits audio signals as pulses of light, making it immune to interference [source: ecoustics.com]. Another type of digital audio cable is digital coaxial, which resembles the old coaxial cables used for satellite dishes or cable TV, but is specifically built to carry digital audio. You can find optical and digital coaxial ports on newer DVD players, CD players, and stereo receivers.
The final audio-only cable we’ll mention is the analog multi-channel cable. This cable is meant for use with special players like DVD-audio, which play discs recorded at high sample rates for top-tier sound quality. Analog multi-channel cables come with six to eight bundled RCA connectors, each representing a different audio channel on the back of a stereo receiver.
Next, let's dive into video-only cables, which can be a bit more complex.
Video Cables
The most commonly used video cable is composite video. This cable features a yellow RCA connector, typically bundled with red and white RCA analog audio cables. It’s called composite video because it combines all video information—color, brightness, and sync—onto one cable [source: Miller]. Composite video cables were designed for older TVs and have a maximum resolution of 330 lines. While they’re adequate for watching VHS tapes on an old TV, they won’t provide satisfactory results on newer or HDTVs.
S-video cables provide an upgrade over composite video, offering a maximum resolution of 400 lines. You can easily identify an S-video cable by its circular, nine-pin connector. It enhances the image by separating color from picture data, producing a clearer picture. Despite being available on numerous TVs, DVD players, and home theater receivers, S-video's early rise was soon overshadowed by component video.
Component video cables consist of three RCA connectors: red, green, and blue. With component video, color is not only separated from the picture, but the color data itself is divided into two separate channels [source: Miller]. This results in a sharp image with rich, saturated colors. Component video cables are perfect for connecting HD video devices like Blu-ray players and HDTVs, with many home theater receivers providing multiple component video ports.
DVI (digital video interface) cables are specifically designed for high-definition video equipment, such as HDTVs. These cables feature large 18-pin connectors, resembling those used in computer systems. DVI cables provide the same image quality as component video, but with the added benefit of HDCP (High-bandwidth Digital Content Protection). Some critics argue that the HDCP feature can lead to compatibility issues with certain devices.
Lastly, we’ll explore three cable types that carry both audio and video signals.
Audio/Video Cables
In Europe, SCART cables are the preferred choice, while in the United States, composite cables are more commonly used.There are several cables that carry both audio and video signals. One of the earliest options was coaxial video cables. These cables feature the familiar single-pin connector, sometimes called a 'stinger,' which can be either pushed or screwed into place. Today, coaxial cables are mostly used for external connections, such as satellite or cable TV lines that enter through the wall. A single coaxial cable is capable of carrying both audio and video signals.
HDMI cables are an evolution of DVI. They were created for high-definition devices but have a more compact connector, similar in size to a large USB cable. HDMI also supports HDCP copy protection. While manufacturers often claim HDMI cables are the best option for connecting HD devices, this isn't strictly true—DVI cables can perform just as well. However, all three types are equally effective when used with an analog TV [source: Cobalt Cable].
In Europe and the UK, the go-to dual-purpose cable is called SCART (Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs). SCART cables feature large, 21-pin connectors. These cables in Europe combine the functions of RCA analog audio cables as well as composite, s-video, and component video cables, but they can't handle high-bandwidth digital signals required for high-definition TVs. HDMI is the preferred choice for HD devices in Europe.
FireWire, also known as IEEE 1394, is commonly used to connect devices to computers, though some premium home theater receivers and HDTVs are equipped with FireWire ports. FireWire supports compressed MPEG-2 video and digital audio. You could use a FireWire cable to link a digital video camera to your home theater system and display raw footage.
To summarize, here are the cables typically used for different home entertainment setups.
Home stereo system (CD changer, stereo receiver, speakers):
- Lower-end: For regular CDs or MP3s, all you need are RCA analog audio cables and speaker wire.
- Higher-end: If you're aiming for cleaner digital audio, opt for optical or digital coaxial cables and thicker speaker wire.
- Highest-end: For the ultimate DVD-audio experience in full surround sound, you'll require dedicated DVD-audio cables and 12-gauge speaker wire.
Home theater system setup (Blu-ray player, DVD player or VCR, video game console, home theater receiver, TV, speakers):
Home theater system setup (Blu-ray player, DVD player or VCR, video game console, home theater receiver, TV, speakers):
- Lower-end: If you own an older standard-definition TV and primarily use your system for regular DVDs or VHS tapes, a composite video cable paired with RCA analog audio cables will suffice.
- Higher-end: For newer standard-definition TVs, upgrading to component video cables is highly recommended, though RCA cables will still work fine for audio.
- Highest-end: When you switch to high-definition, you’ll need either component video cables or one of the two copy-protected options: DVI or HDMI. Additionally, you should invest in a thicker gauge speaker wire to enhance your surround-sound experience.
