Cable Conundrum

Separating the S from the XLR, the USB from the VGA or the DVI and giving you the ABCs on choosing the right cable for the right price.

 

Anyone who has ever linked one tin can telephone to another with a piece of string knows the value of a good connection. But, if you're like most editing enthusiasts out there, choosing the right cables for your suite is sometimes a confusing prospect.
Now don't think reading this article will magically make that mass of black coils under your desk turn into a pristine collection of cable. Tidiness is not the issue here. What is at issue is keeping you running smoothly at the best price. So, let's start with some basic definitions of which does what and at what price.
 
Composite Video
You've seen these a thousand times. They commonly come as singles, as pairs or as an audio/video three-way. Often called RCA cables, they transfer stereo audio and video signals between components. It's best to keep your RCA connection as short as possible and away from power lines, which cause interference.

You could choose to spend a fortune on these connectors; however, a standard length at a consumer electronics store will suffice for almost any need and usually for under $10.

    
Composite S-Video XLR

S-video Cables
The "S" which stands for "Separate" (but is often referred to as "Super") simply means it transfers the video information using two separate signals. Unlike composites, S-video cables carry the luminance and chrominance on different signals, improving the quality by reducing crosstalk between the two signals.
There are several types of S cables, and they serve different functions, based on their number of pins. The most common is the 4-pin used for video applications, while other S cables, like the 7-pin, are often used for computer hardware applications.

As with most other cables on the market, S-video connectors can be inexpensive; however, less expensive typically means lower quality, especially in the pin strength. You can expect the cheapies to snap more easily. If you're going with an S-video cable, go with quality. In this case, quality still costs you under $30
 
 
XLR Connector
While you will find tons of RCA connectors in the consumer world, these rugged connectors are still the standard in many professional audio setups. The name comes from the originator, the Cannon X series connectors. The remaining "L" and "R" stand for its defining qualities: "L" for the latch that keeps the connector connected and "R" for the rubber that encases the contacts. Since the original, XLRs now come in a variety of configurations; however, the 3-pin setup is the most common. When using balanced signals, XLRs are built to block electrostatic noise and reduce annoying buzzing, humming and any sort of radio interference that could find its way into a professional production or post environment. (See A Little Balance by Hal Robertson in the August 2005 issue for more information on balanced audio.)
For all they do, you'd expect these babies to run a lot more than they do, but you can find quality XLRs (depending on length and the manufacturer) starting around $10 for 6 feet.

USB Cables
USB is an acronym for Universal Serial Bus. You can find USB cables just about everywhere you find a computer. USBs were originally designed to allow the connection of peripherals without the need for costly expansion cards. They transfer data through a twisted pair of data cables and come in different speeds for delivering data. Earlier versions of USB have little bandwidth for full-frame video, but they are still good for use with keyboard or mouse connections. Hi-speed USB connections (USB 2.0) deliver data at a rate of around 480 megabits per second (abbreviated as Mbps or Mbit/s). That makes USB 2.0 fast enough to handle Mini DV data rates.
You can find USB cables in a variety of lengths. If you want to hook up several peripherals to your computer at once, you can use a connection hub. However, these "connect-all" cables do have their limitations. Many USB devices draw power and thus require their own power source if not plugged directly into your computer. This sometimes makes hub use cumbersome and ineffective.

Depending on your needs, it's not terribly hard to find some USB cables for under $3, but just be careful. At prices that low, you may just get what you pay for.

    
USB BNC FireWire

   
FireWire Cables
If you've ever heard someone reference an i.Link or IEEE 1394 input, don't be confused. It's just a fancy way of talking about FireWire inputs or cables. Over the last several years, FireWire has effectively replaced those behemoth multi-pin SCSI cables in almost all A/V applications, thanks to FireWire's small size and relatively fast transfer rate. FireWire 400 connectors, capable of transferring up to 400Mbit/s, come in 4-pin and 6-pin configurations and a wide variety of lengths. If you need more length than a typical office setup requires, you can daisy-chain FireWire cables to suit your needs. The 9-pin FireWire 800 can do just what the name implies: transfer up to a whopping 800Mbit/s. Back in their early days, these cables were not exactly cheap, but now that they've become more standard, you can easily find a trustworthy FireWire connector for a price that is wallet-friendly.
   
 
DVI Cables
Are you ready for some Digital Visual Interface? If you want the best picture out of that new flat-panel LCD or digital projector, then you'll need one of these bad boys.
The DVI interface uses a digital protocol to carry uncompressed digital video signals to your display. DVIs control data transfer through four pairs of twisted red, green and blue wire, and they control such issues as signal crosstalk and pixel brightness. DVI cables have started to take over in situations where analog VGA cables just don't have the juice. With DVI, the length of cable matters less than with other video cables, but they are generally very expensive, no matter what length you choose.
HDMI Cables

With HDV and AVCHD camcorders sporting HDMI outputs, it's time to discuss the High Definition Multimedia Interface connector. In theory, it's much like DVI, in that it transfers digital, uncompressed information from one device to another. You can easily adapt DVI to HDMI, too. However, HDMI is more commonly used for home entertainment devices, since it is also capable of transferring digital audio bitstreams. It has an impressive high bandwidth of 10.2Gbps (HDMI 1.3 specification). HDMI will transfer not only high-definition video information, but also multi-channel digital audio and a type of digital rights management technology called HDCP (High-bandwidth Digital Content Protection).

HDMI cables are somewhat pricey, but, as more HDTVs and high-definition camcorders penetrate the market, the cost should go down. Currently, a 3-foot HDMI cable will run about $60.

Some people like to call that mass of twisting, twining, knotting cables behind your gear "black spaghetti," and, like the pasta it resembles, it can be a mess figuring all of it out, but we hope we've at least given you an understanding of the acronyms and use. Once you've got the cables in place and have signals running through them, keeping them lined up and orderly is up to you!

Michael Fitzer is an Emmy award-winning commercial and documentary writer/ producer.  VIDEOMAKER Sept 07