Convenience of IP Theodore AL

Its taken a couple of years for the industry to come around, but now most major makers of distributed home A/V and lighting systems offer control interfaces based on IP (Internet Protocol) technology. And well they should: the cost and convenience benefits of control over IP, including the ability to use PCs, PDAs, and other web-enabled devices as controllers, makes sense for customers as well as installers.

Lets not, however, lose sight of an important fact: for all the companies jumping on the convergence bandwagon and aggressively promoting their prowess with TCP/IP, nearly all systems still distribute content, particularly audio, the way theyve always done: via analog, either with balanced, low level signals to an in-room amplifier, over amplified speaker cable from a centralized system to a remote zone, wirelessly via radio frequency (RF), or a combination of these options.

In reading the ads and brochures from these companies, one might not immediately realize the divergence between digital control and analog content. Many firms so tout their digital, IP-based controls that one would think they were digitizing and streaming all their signalscontrol and contentover a home Ethernet network. They arent.

There are some significant technical hurdles to convey content digitally over IP. The major challenge is time synchronization. Imagine what would happen if, when walking room to room, the music was one-tenth of a second out of synch, and then imagine that difference across four or five zones in a house. While synchronization isnt a requirement in common Internet applications like e-mail or desktop streamingit doesnt matter if everyone gets a message or receives a streaming newscast at exactly the same momentsynchronization is an absolute necessity in a home entertainment network.

With synchronization solved, though, there are many advantages in sending content over TCP/IP and in structuring a home A/V distribution system as an Ethernet network. Perhaps the single greatest benefit is eliminating problems with noise and signal loss, regardless of the length of a cable run or the presence of other electrical and electronic equipment. Digitizing and transmitting (i.e., streaming) content over IP protects signal integrity while enabling bit-for-bit fidelity with source material including DVD Audio and HDTV.

A second and related benefit, and one never before realized in home audio, is being able to keep signals in the digital domain until they literally reach the speaker, minimizing or completely eliminating speaker runsanother source of noise and loss. By using IP-based digital amps that are either co-located or integrated with an in-wall or in-ceiling speaker, analog signal paths are kept to absolute minimum lengths.

There are additional and exciting possibilities within this scenario: designers are already working on digital IP-based amps which, based on music metadata contained in the IP stream, automatically change crossover frequ...

Click here to read the rest of the article from Residential Systems