If you've paid to have your HDTV installed in any kind of permanent way, you know that the cost of installation can often overtake the cost of the television itself. Part of that installation cost involves wiring: running cables from your gear up to the TV, generally through walls. In addition to the high price of long cables, especially HDMI cables, punching holes in walls and making the installation look clean costs big bucks.
In that light, the $300 price tag of the Acoustic Research HDP100 seems reasonable enough. This system is designed to transmit HDMI signals, which consist of audio and video, from your components to your HDTV without having to punch holes in walls or invest in long, expensive cables. It does so in the same way that Ethernet-over-powerline adapters work: using your existing AC power lines and wall sockets. I've had good experiences with Ethernet powerline adapters so I figured the HDP100 would be a great solution to the cables-through-walls problem.
While it generally worked as advertised, the system didn't wholly deliver on its promise, especially to eagle-eyed viewers who might expect the same performance seen from standard HDMI cables. Yes, longer HDMI cable runs can have their own issues, but in my experience they deliver better performance than the HDP100. For now, however, this is the only system of its kind available--wireless HDMI systems are largely vaporware or proprietary, and few other options for HDMI installation exist--so you might not have a choice. If you're a potential buyer of the system, you should also make sure to purchase it from a vendor with a good return policy in case it doesn't work in your location.
The HDP100 system consists of a pair of identical-looking, glossy-black boxes about half the width of a standard DVD player, measuring 8.5 by 5.3 by 1.6 inches (WHD). One is a transmitter and one a receiver. Each has a trio of blue LEDs on the front panel--to indicate power, a link to the other box, and the presence or absence of data being transmitted--and on the back panel, a port for the included infrared extenders (see below), an on-off switch, an HDMI port, and a thick power cable. The company includes a pair of stands for orienting the boxes vertically, along a single wall mount kit and a short, 3-foot HDMI cable.
The HDP100's feature set is quite simple. Each box only has one HDMI connection, so you can't connect more than one component directly to the transmitter box or pass through a connection. The system will take the HDMI output of an AV receiver or HDMI switch, enabling more than one source to transmit to the display, as long as compatible signals are transmitted. For some reason the system is compatible with only progressive-scan video signals: 1080p, 720p, and 480p. It can't pass high-def 1080i or standard-def 480i signals, so be sure to set your source components to output in progressive-scan over HDMI. The system will also transmit audio, of course, although you need to make sure your TV is capable of decoding the audio from the source component or you won't hear anything.
Acoustic Research designed the system to work not from room to room, as most powerline Ethernet systems do, but rather within the same room, as a way to avoid running wires from components to a (typically wall-mounted) HDTV or perhaps a ceiling-mounted projector. In my tests I was able to make a successful connection using various power outlets around the room where the TV was situated, as well as from one or two rooms away within my apartment. Longer connections were unsuccessful. As with all powerline systems, you may experience better or worse results depending on the state of your electrical wiring. A room-to-room installation is certainly viable, especially with the HDP100's infrared transmitter system, but that's not how the system was designed.
The receiver has an IR window on the front panel, and a port for the included external IR sensor. The transmitter has a matching port for the included IR blaster. You can place the external sensor in a location where it will pick up the infrared signal from a remote control--typically near the TV's own remote sensor--and the blaster in front of the connected HDMI component's own IR sensor. Using this arrangement, the system allows you to control your HDMI component using its remote control, or a universal remote, even when the component and the HDP100 boxes themselves are stashed out of sight or in another room.