Technology Tuesday: splitting HMDIs signals

I’m late to the party on a lot of things. Add Roku to that list – I just bought one a couple of weeks ago. But in doing so, it brought up a technology issue that I hadn’t thought about in a while: how to direct, from multiple sources, video to one device and audio to another. My dilemma was exacerbated by the video and audio equipment that I have.

When I bought the 65″ TV I have in my den, DVI was state-of-the-art for high definition video, while Dolby 5.1 was the gold standard for audio. Life was pretty simple: I connected my DirecTV set top box to my TV for video and to my receiver, via an optical cable.

Not long after, DVI was pretty much scrapped in favor of HDMI, which carries video and audio in a single cable. For those of us with DVI-only TVs, an HDMI-to-DVI cable solved the problem. I’m not sure exactly when I put this cable into my system – it was so long ago that I had completely forgotten about it. Having only one source – now a DirecTV HD DVR – hooked up meant that I really didn’t have to think about it.

That is, until I got the Roku 3.

Somewhere along the way, I picked up a one-out, 4-in switch box, probably to hook up my Blackberry Playbook to watch something broadcast on the internet (like a football game on ESPN3). I didn’t think about why the sound was not working properly – it wasn’t being passed to the receiver. But once I tried the Roku, I had to think about it – and track the cables to see why it worked perfectly on the newer TVs in the bedrooms – they have HDMI input – but not on the den TV. Duh! No HDMI on the TV! So what I needed was a device to split the HDMI signal into separate audio and video.

I started searching for an HDMI to DVI+optical converter. I found two: both (1, 2) had been discontinued. I surmised this was because of the proliferation of devices that split out the audio of HDMI, allowing for the routing of the audio signal to a source separate from the video. And some of these had 4 (or more) input sources. I decided to give one of them a try.

I spent a week trying to make this box work. It handled my DirecTV box and laptop just fine. But I couldn’t get any video from the Roku 3 and any audio from my Playbook. I sent the first box back and got a second one – no luck. I replaced all of the HDMI cables in the setup with higher gauge cables – I had been told that these splitter boxes put a lot of pressure on the cables. Still no luck.

So I decided to try a different switch box. It arrived Saturday morning and everything works as it should.

Not being an engineer, I can’t explain why one works and the other doesn’t. It may be the different HDMI standard: the first box used 1.4 while this one uses 1.3. Supposedly the newer standard is more taxing. As I have no plans to replace all of my equipment any time soon, I’m just glad to have found something that works.

Now – back to more Downton Abbey 😉