Finally – Wireless HD that Works

Gefen beams up to 1080p video across a room

By Sean Captain Posted 01.06.2009 at 10:00 am 11 Comments

The Gefen HDMI UWB Extender

Like perfect cellphone reception, wireless HDMI is a radio technology that’s long been promised and has shown little sign of materializing. But finally, it’s here. Gefen’s HDMI UWB Extender is not the first high-def A/V streamer to hit the US. (Sony’s Bravia Wireless Link has that distinction). But it’s the first that can fully replace an HDMI cable by offering up to 1080 progressive HD video.

“Finally” is certainly the word for this product. Gefen announced it nearly two years ago and promised delivery in Autumn 2007. But it was worth the wait.

Better than Promised
Per Gefen’s list of preconditions in the product literature, I set up the system in a single room, with about a 30-foot gap between transmitter and receiver (the max they guarantee). And I left a clear line of site between them. Gefen is cautious in its claims because of an in inherent weakness in the ultra-wideband (UWB) technology the HDMI UWB Extender uses. UWB is great for transmitting large amounts of data because it utilizes a broad swath of frequencies. But to keep these data bursts from interfering with neighboring networks on the same frequencies, its power and range are kept very low.

I got virtually perfect reception both in an office conference room and in my living room (with the receiver sitting right next to a Wi-Fi router). The Extender worked not only when I followed Gefen’s guidelines but also while I broke all the rules, even standing in front of both the transmitter and receiver and even putting the transmitter in another room, behind a steel door. (In fact, only wrapping my hand fully around the antenna killed the transmission.) Most important, I had no problem when I stashed the receiver behind an LCD TV. After all, what’s the benefit of eliminating the unsightly cable if you can’t also hide its unsightly wireless replacement?

Hi-def streams from a Blu-ray player and an AppleTV looked perfect—without any fuzziness or stuttering. Colors were spot-on, and audio was crisp. To really test quality, I also hooked up a Sencore VP401 signal generator – which TV pros use to diagnose problems with sets. The Sencore produces pristine test patterns such as color bars, brightness gradients (from black to full white) and fine-grained patterns that will break up conspicuously if there is the slightest glitch in reception.

Though connecting the Extender to the Sencore didn't produce quite the same quality as an actual cable connection, I had to look closely to see the difference. For example, I noticed very slight ghosting (double images) where two color bars met, and a bit of shimmering on a screen jam-packed with fine text. (By comparison, Sony’s Bravia Wireless Link crashed while trying to display some of the more-intricate patterns.) It’s very doubtful that any of these weaknesses would produce perceptible errors when real video is playing. I certainly didn’t see anything with my HD test material. Gefen says that they have made some firmware improvements that may fix even the miniscule problems I saw.

My one complaint is noise. Both the transmitter and receiver have cooling fans that give off a perceptible whooshing sound. Crank up the volume even moderately, though, and the sound is drowned out.

Who Cares?
Now that we know the Extender works, we have to ask an important question: Does it matter? The kit sells for a whopping $999. Meanwhile, you can buy a high-quality 30-foot HDMI cable for about $40 online. (Never buy one in a store like Best Buy. The markup is huge.) The cable might not be pretty – especially if, say, you are running it up to a ceiling-mounted projector. But the $959 you save should be more than enough to hire a contractor to hide it behind the wall. (The $40 cable I mentioned is CL2 rated for in-wall installation.) Or you can try Flatwire’s upcoming tape-like HDMI cable that you stick to the wall and then cover with spackle and paint.

Of course Gefen's provides more flexibility. You can re-arrange the furniture without having to re-route cables. And you can use it in places where tearing into walls isn’t an option—such as a rental apartment. It’s also handy for temporary setups, such as in conference rooms.

And as wireless HDMI offerings (and competition) grow, prices will inevitably drop. We expect to see at least a few products from mainstream companies at the Consumer Electronics Show this week. They will likely use yet another radio technology called WirelessHD. Stay tuned.

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11 Comments

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moodray

01/06/09 at 12:17 pm

Finally!! I've been waiting for the release of this product, and it's here. My wife won't let me put an LCD above the fireplace because of the wires showing. Now I can place the Gefen wireless receiver right on the mantle (it actually looks pretty cool from the pics). It will be a sweet little conversation piece too... Thanks for the detailed review; I was a little skeptical about the video quality not being spot-on.

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vincent_yeh

01/09/09 at 9:18 pm

But I am worried about wireless HD in my house.In fact wireless HD still faces problem such as it can't transmit av to multiroom and seriuos interference still occurs everywhere.All I want is a clean and pure AV environment,no any enemy comes inside.
I expect to see powerline technology growth.Powerline has advantage in house environment,powerline+HD video will be another considerable technology too.Meanwhile powerline is ideal use house inside not public space.
Finally I want to see cost more effective between powerline and wireless HD.Anyway two kinds of consideration will increase more useful applications in future.

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chad98036

01/12/09 at 2:25 pm

Actually Avocent has had a fully HDMI / HDCP compliant product on the market since 2005. The MPX series uses 802.11a/g/n and JPEG2000 to deliver it's content. The advantage to this approach is that it allows central distribution to a house, store, auditorium etc. vs. a short range one to one solution.

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moodray

01/15/09 at 3:00 pm

If that was the case, I would have bought one already. The Avocent solution is NOT HDCP compliant. Without being HDCP compliant, this solution doesn't work with Blu-Ray, PS3, normal Cable or Dish boxes, etc.

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chad98036

01/16/09 at 12:40 am

@moodray,

really? I would like to know how you came by this information?

I worked on the project and it is HDCP compliant and was tested in operation with Blu-Ray, HD-DVD, X-Box, and PS-3 as well as a number of other content protected systems and I happen to know that Avocent pays a license few to purchase HDCP keys with every production run.

Of course popular science could just contact Avocent and get a testing pair and tell us whether it is HDCP compliant or not but for some reason for the last 3 years they have been reluctant to do so.

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moodray

01/30/09 at 4:47 pm

chad: obviously you're biased on this subject...

Nowhere on the description of the Avocent solution does it say HDCP compliant. That would be a huge selling point, don't you think?

I'm sure other readers would rather hear comments from neutral observers. Thank you.

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bc501

02/24/09 at 1:36 pm

On searching the Avocent site, I discovered that their MPX series units are indeed HDCP compliant.
You will find that stated on this page which is for the MPX1500, under Digital Video Standards, under Video Details...

http://www.connectivity.avocent.com/products/emerge/mpx1500.asp

But you have a good point, Moodray -- why on earth would Avocent not make that clear on their main features listings?
I was at CES in Las Vegas, and told friends that "finally, there was an HDCP-compliant device coming" because there was no indication the Avocent was.
Chad98036, you may wish to suggest to your former colleagues that they change their website to make it clear that the MPX's are HDCP-compliant, as they've missed out on a lot of sales over the past few years!

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bc501

02/24/09 at 1:36 pm

http://www.connectivity.avocent.com/products/emerge/mpx1500.asp

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cpheterson

04/27/09 at 1:32 pm

I am the product manager for the Avocent MPX products. The products are HDCP compliant, as indicated on our web site. This information was not highlighted because that is not a very important feature in digital signage markets, where the product is positioned. Thanks for the heads-up regarding other markets. I'll be sure to highlight the feature more prominently.

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ddharia

05/27/09 at 5:54 am

@ vincent_yeh: powerline, moca, etc. dont have bandwidth for real HDMI transport.

@ everyone: HDCP? The comments got sidetracked... these boxes including Avocent's transmit HD (not HDMI) video. HD video is typically in tens of Mbps(20 to 80 Mbps) and HDMI is in the order of Gbps (>1, typically 1.5 Gbps (HDMI 1.3), and higher for HDMI 1.4). These boxes dont transmit HDMI "period".

So, if the TX box connects to a DVD/Blu Ray's HDMI port, it has to decrypt it (HDCP compliance) and recompress it to MPEG or JPEG2000 before *wirelessly* transmitting. Right there is the problem (lost resolution). Then it gets to the RX box and gets reconverted into HDMI, reencrypted (HDCP compliant) and is output through that HDMI connector to be connected to the HDTV's HDMI port. Big deal.

Now I gotta pay in the upwards of $750 to $900 to watch compressed video? NO SIR.........!!!

HDCP compliance here means nothing. What is to be the focus is that there is no product, and I mean NO product, in the market today that can stream "uncompressed and encrypted (HDCP)" data that comes out of the HDMI port wirelessly. There's just enough wireless bandwidth available to do that.

WirelessHD has the bandwidth but beaks the link when someone as much as coughs in the room due to line-of-sight issues. Moreover, it works for like 10 ft. Not much of a product there.

WHDI has the range (similar to that of WiFi) but uses encoding/compression/truncation, whatever you may wanna call it which again leads to lost resolution.

Need higher bandwidth technology to really solve this problem, and there are technologies out there that will give you that today - it's just that the big companies will take a while before they finish shooting their feet and start accepting their folly by backing the sub-optimal solutions... But there is no way anyone should pay for such cheap boxes (not cheap in price though). So the question to really ask is...

"Now the heck would I wanna pay a thousand bucks and watch a low resolution compromised video on my $3000 LCD HDTV?"

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jeremytaylor

08/04/10 at 12:05 am

Finally!

But that was it until I saw the price :(
Guess I'll hold on to my HDMI cable for now. However, I seriously doubt having one of these will greatly improve my Audio Visual experience at home. It makes more sense and worth for offices, product launches, The White House, etc.

www.piranha-audiovisual.co.uk