Gefen CAT-5 HDMI Extender: EXT-HDTV-CAT5
2/9/2006 by Art Feierman
Gefen offers a wide selection of extenders, switchers, converters, distribution amplifiers and cables.
Gefen seems to be particularly successful with their modestly priced Extenders. For those requiring longer runs for DVI or HDMI, than can normally be accomplished with conventional cabling, Gefen offers two versions, one based on DVI, the other, HDMI. The part number, and more information on the DVI version is found below.
Either version retails for $499 at the time of this review.
I found myself in the situation of redoing my home theater room (one of two rooms I use for evaluating projectors). Due to the large size of my room, plus the high ceiling (cathederal, it peaks at 21 feet), and the location of the equipment relative to the shelf mounted projector in the back of the room, I needed a solution that would cleanly transport my digital source material a little over 100 feet. I needed to get a digital signal from my Marantz receiver (with 2 DVI inputs and one DVI output), to the projector (a BenQ PE8720 which has a single HDMI input).
Unable to find traditional high performance DVI or HDMI (and still very expensive) cabling that runs longer than 20 meters (almost 70 feet), I turned to alternative technologies. I've seen very expensive laser systems at trade shows, fibre-optic solutions, repeaters, and extenders. The extenders seem to be the lowest cost solution that would work for me, and, I believe for most people with long distances to cover in their home theater, or other digital environments.
Being basicly concerned with keeping costs under control, I decided on Gefen's CAT-5 HDMI extender. Gefen claims the device works at distances of up to 150 feet, using CAT-5 cabling. I'll say right now, that it was simple to install, and works beautifully. Here's the scoop:
As mentioned earlier, there are two versions - one is DVI, and the other (which I went with) is HDMI. Both are HDCP compliant.
The Gefen HDMI extender consists of 3 pieces; a base unit (Extender-S, the sender), a remote unit (Extender-R, the receiver), and the power supply. Gefen also includes in the box, a 6 foot HDMI to HDMI cable. The base unit sits by your digital source, be it a receiver, HDPC, or individual digital device (cable box, satellite receiver, DVD playe)r... It draws power from the typical "brick" power supply (5 volt, in this case), like those that come with your laptop. I should mention, that to look at them the only physical difference between the HDMI extender and the DVI version, is that one has an HDMI connector on the sender and receiver, the other, has DVI connectors instead. From a practical standpoint, HDMI also transmits audio, and supports CEC (consumer electronics control), based on AV.link, which allows control from a universal remote. Note, the CEC is a difference between DVI, and HDMI, but the actual Extender has no remote sensor, it simply carries the information.
The remote (Sender) box sits by your projector, plasma, or other display device, orr for that matter, any device that you have, that needs to receive a DVI or HDMI signal from a source a long way off.
The two Gefen boxes are connected by a pair of CAT-5 cables. Gefen recommends that one of the cables be shielded CAT-5 (that carries the digital signal). For the other cable they recommend CAT-5e. That CAT-5e cable carrys both powerand also "command and control", to the remote box.
Of course CAT cables are about the easiest thing you can run through your walls. Installation of the Gefen extender system consisted of running the CAT cables (along with all the other cables) up the wall, across the attic, across to part of the ceiling with no attic, and back down to the projector on the shelf. Best cable length estimate from the people who installed everything was that the CAT cables each ended up being between somewhere between 105 and 110 feet in length.
My Oppo DVD player and my Cox cable box both output DVI. Both have short DVI cables (1 meter) running to my Marantz receiver's DVI input. From there, I used a a short, 1 meter (Ultralink brand) DVI to HDMI cable, to connect the receiver to the Gefen Extender S. (Gefen provides a 6 foot HDMI - HDMI cable with the package, which I did not use).
The Extender S (sender) unit has one HDMI input, and two CAT-5 outputs. From the Sender, the two CAT-5 cables run all the way to the Extender-R sitting next to my projector on its shelf.
As it turns out my projector has an HDMI input, so a short, HDMI to HDMI cable connects the Extender-R to the projector. I chose to use a .5 meter HDMI-HDMI cable, instead of using the Gefen provided 6 foot cable, in order to have less cable "hanging around".
Here's the best part: I fired up all the equipment, did all the necessary settings on my receiver to output my digital sources the way I needed, and set my projector to HDMI input.
Almost to my amazement, I got it all right the first time, and a beautiful digital image appeared on the projector screen. I immediately started looking for the kind of flaws I had previously enountered with longer length DVI and HDMI cables, such as lots of noise visible in very dark areas. (I've seen major "noise" - many of the pixels that are supposed to be dark, come in very visibly red, when using some 15 and 20 meter cables).
The signal is clean as far as I can detect from viewing 1080i coming from the cable box through the receiver and extender, and 720p coming the same route from by DVD player. I do not currently have a 1080p source to confirm its maximum spec.
Before my room was completed, I had previously used the Gefen Extender with shorter runs of CAT-5 cabling, hooking up digital to several different projectors, directly from a Bravo D2 DVD player (DVI out), and also the same player through my Marantz. I encountered no issues with any configuration that I tried.
So, what we have here, is a solution that works. It allows you to run longer lengths that traditional cables, but is limited to 150 feet. (that should be sufficient for virtially all home theater installations. It might, however, not be long enough for a house with a central video server where you need to send out DVI or HDMI video to a different room far, far, away.
The Gefen Extender is a simple solution, easy to install, and works beautifully. Affordably priced compared to many other "longer distance" solutions for DVI or HDMI, the Gefen Extenders earn our Hot Product Award.
Dimensions (each, Sender, Receiver): 3.4"D x 3.25"W x 1.25"H
Weight (shipping weight: 3 lbs.)
Bandwidth: 1.65 GHz
Range: 150 feet
Resolution (Single Link Range): 1080p (1920x1080)
Input Video signal: 1.2 volts p-p
Input Power (DDC signal) 5 volts p-p (TTL)
Link connector (between sender and receiver: RJ45 (two each)
Power consumption: 15 watts maximum
For those prefering the DVI version:
All provided specifications are the same, except that this unit has DVI connectors on both the Sender (from the source), and the Receiver (to the display). Also, as mentioned above, as it is DVI only, it does not carry the audio or CEC information, which are on HDMI, but not DVI.
Gefen Extenders and other products are available directly to end users from their website, but also sold through selected audio/visual dealers.