Digital A/V connectors like HDMI and IEEE 1394 simplify hookups and improve signal transfers. But are they future-proof?
When a federal court this spring put the nix on an FCC requirement that video equipment start implementing a broadcast flag copy protection scheme, the sighs of relief among consumer electronics manufacturers were not just an affirmation of the consumer's right to record. From a purely pragmatic standpoint, manufacturers were also relievedthat they would not need to re-design their products' connectors.
By Cliff Roth
Digital video and audio connections have numerous inherent advantages over analog connections. They're virtually impervious to noise pickup, and signal quality doesn't degrade as cable lengths increase (up to the maximum allowable cable length for the connector).
Despite the advantages, though, one yearns for the days of analog connections in one respect: simplicity. In the good ol' days of analog, a phono jack was a phono jack. Either it was an input or an output, and it stayed the same.
Today, the digital jack—the physical connector—is just half of the connection. The software—the digital protocol allowing two or more pieces of equipment to talk to each other—is the other half (see sidebar on page 62). It's both input and output, and it's subject to change at any time. This ability to change the protocol while leaving the physical connector the same can be confusing.
The era of digital A/V connectors has really only just begun. The biggest changes are yet to come. Numerous variations of the popular DVI connector, found on many computer monitors and big-screen home theater monitors, already exist. The IEEE 1394 connector has transformed into a general-purpose A/V transport system (albeit with compressed video quality) that each brand can customize. The newest digital connection, HDMI, already comes in two forms, and is a political hot potato likely to require new versions.