|Fire in the Wire The Future of Audio Interconnects|
|Home Theater News Cables News|
|Written by Richard Elen|
|Thursday, 11 July 2002|
There are plenty of complexities involved when setting up a home theater system, but for most of us the really annoying bit is hooking up the different sources and getting everything to successfully talk to each other.
Luckily, with some new developments poised to appear in the home entertainment marketplace, all that’s about to change.
The reason is the development of a powerful new version of FireWire, Apple Computer’s super-high-speed serial digital interface that became an international standard – IEEE1394. In fact we can now all use the name “FireWire”, as Apple has made it available to the 1394 Trade Association for any manufacturer to use – and of course, “FireWire” is much sexier than “IEEE1394”.
FireWire has been standard on Macintosh computers for several years, along with USB, regarded by many as a competing interface standard, and Wintel machines have been a lot slower to catch the FireWire bus than Apple (who thought of it) – but that’s all changing.
In addition, the fact is that USB and FireWire are really very different. USB is basically a way to hook a peripheral to a computer. FireWire, on the other hand, is a powerful networking system that can carry almost any kind of digital data and control signals – notably for us, including digital audio and video – from one piece of equipment to another. And FireWire is so intelligent that you don’t even necessarily need a computer.
Regular FireWire – aka “1394a” can carry signals at 100, 200 or 400 megabits per second (Mb/s) – called S100, S200 and S400 respectively. But the new incarnation is a lot faster than that: it can handle data at 800 or even 1,200 Mb/s – “GigaWire”. Even regular 1394a can handle a lot of high resolution digital audio plus a respectable video stream. GigaWire goes several steps further and allows high-definition video along with the highest-quality audio that’s worth doing – 24 or even 32 bits, and sample rates like 96 and even 192 kHz: the best that DVD-Audio can offer.
And whatever the FireWire flavor, that data all goes down one cable. Plug your DVD-Audio player into your receiver with one wire. Your receiver into your digital speakers with another. In fact, you could possibly daisy-chain yourself around a future system, linking one item to the next with a single cable between each unit. With 1394a, each cable isl imited to about 4.5 meters long. With 1394b, the limit is more like a hundred meters – and there are several types of interconnect to choose from: including Ethernet-like wire, fiber optics and even wireless. In addition, 1394a and especially 1394b provide a true multi-level network infrastructure, with backbones linking hubs that feed local components.
Another neat thing about FireWire is that it’s an international, open standard. There are agreements that will enable everything to talk to each other, irrespective of the manufacturer. A multi-level protocol called HAVi (Home Audio Video Interoperability) complements FireWire by adding an icon-based user interface. Each unit in the system reports to the network what signals it can generate or receive and what it can do, and with a controller you can define the signal paths and the way in which the system is controlled. Mitsubishi have already implemented a HAVi-based system they call “NetCommand”, which makes their large-screen TVs the control center for your FireWire-connected home theater system. Not only can NetCommand handle 1394-based components, but infra-red blasters can be attached to the system to control legacy equipment. In addition to Mitsubishi, Grundig, Hitachi, Matsushita (Panasonic/Technics), Philips, Sharp, Sony, Thomson, Toshiba and others have committed to producing HAVi-compliant, FireWire-interfaced products.
There is now a protocol for allowing copy-protected data to be fed from a DVD-Audio player to a receiver or converters, and it uses FireWire to carry the information. It’ll integrate fully into the audio networks of the future. There’s also a digital interface specification for Super Audio CD. So even the highest quality audio-video components will be able to become part of the FireWire digital matrix.
In fact, FireWire-based components have turned up at CES and similar events for at least the last couple of years. The reason that nothing much seems to have happened is that there are only a small number of silicon manufacturers producing the chips, and in addition, 1394b has been seen as the technology to wait for. Now prototype 1394b chipsets are starting to be delivered to manufacturers, and the FireWire dream is poised to become a reality. Expect a big change in the audio cable business over the next few years, as hooking up your home theater system becomes so easy you’ll need your kids to do it for you.