My receiver has HDMI switching, but I need to drive two displays in mytheaterroom (not at the same time- I have a plasma on the wall and my screen drops down in front of it). Can I use an HDMI switcher routed backwards (run the output of the receiver to the output of the swithcher and run the inputs on the swithcher to each display)? Since HDMI is two-way communication, it would seem logical that this would work. I have been doing this with a component swtcher and it works fine, I just select input 1 and use the PDP and input 2 feeds the projector. Am I missing something?

I don't know of any switches that can be used in reverse. You actually need an HDMI distribution amp.

I don't know of any switches that can be used in reverse. You actually need an HDMI distribution amp.

Correct me if I am wrong, but I thought that most of those are designed to operate two displays simultaneously and gets the handshake from device 1 and device 2 follows device 1. This would mean if you switch off device 2, you would lose the handshake and lose the connection.

What would I need for my setup described on my earlier post?

Correct me if I am wrong, but I thought that most of those are designed to operate two displays simultaneously and gets the handshake from device 1 and device 2 follows device 1. This would mean if you switch off device 2, you would lose the handshake and lose the connection.

What would I need for my setup described on my earlier post?

That would be a flawed design, although I do have one distribution amp that only lets me turn on one display at a time (an older DVI model).

Below is couple I'm familiar with:

Audio Authority 1x2, 1x4, and 1x8 (AA1392, AA1394, AA1398)
Dtrovision HD150 1x5

I don't know of any switches that can be used in reverse. You actually need an HDMI distribution amp.

Hi Kei,

No argument with your statement above, but I was wondering what would prevent this HDMI splitter (http://www.cables4computer.com/newproduct/Prod_Individual3.aspx?groupcode=I3587&program=PT) from working if only one of the displays was powered up. Does the unused leg draw down the signal level too much or cause interference?

The manufacturer states that "Our HDMI splitter cable provides a fast and easy way to simultaneously connect 2 HDMI displays to a single digital HDMI source."

To the OP, might want to check this thread for additional discussion on your topic. http://www.avsforum.com/avs-vb/showthread.php?t=830930

That splitter can only work with one display if HDCP is used. Don't expect to watch anything HD on 2 monitors with it because HDCP will be used. But for $12.00 it may be worth a try if you really need to have it.

larry

That is how I intended to use it, driving either my TV or PJ, exclusive of the other.

But I think I answered my own question by doing some more research, apparently HDMI can interrogate a connected device even if it is off, thanks to a voltage supplied by the source to power the EDID chip in the sink device. So when the source tries to link up, it will get responses from both EDID chips even though only one display is turned on, and declare the link invalid. So much for the inexpensive solution.

That is how I intended to use it, driving either my TV or PJ, exclusive of the other.

But I think I answered my own question by doing some more research, apparently HDMI can interrogate a connected device even if it is off, thanks to a voltage supplied by the source to power the EDID chip in the sink device. So when the source tries to link up, it will get responses from both EDID chips even though only one display is turned on, and declare the link invalid. So much for the inexpensive solution.

Which is why I thought a 2:1 switch would work in reverse. Assuming two way communication and not needing both displays to work simultaneously, it just made too much sense.
I guess I thought incorrectly that the switches allowed full two way communication in both directions. If so it would certainly work the way I described in my original post.

That is how I intended to use it, driving either my TV or PJ, exclusive of the other.

But I think I answered my own question by doing some more research, apparently HDMI can interrogate a connected device even if it is off, thanks to a voltage supplied by the source to power the EDID chip in the sink device. So when the source tries to link up, it will get responses from both EDID chips even though only one display is turned on, and declare the link invalid. So much for the inexpensive solution.

Indeed...I tried this setup for my fp and rptv with no luck. Looks like i'll have to get a switcher.

I don't know of any switches that can be used in reverse. You actually need an HDMI distribution amp.
Kei is correct. Using an ATC certified, HDCP compliant distribution amplifier is the only reliable method of making this work.

She mentioned our Audio Authority products, and I can confirm that they will work with only one display turned on, or both.

Trent

That is how I intended to use it, driving either my TV or PJ, exclusive of the other.

But I think I answered my own question by doing some more research, apparently HDMI can interrogate a connected device even if it is off, thanks to a voltage supplied by the source to power the EDID chip in the sink device. So when the source tries to link up, it will get responses from both EDID chips even though only one display is turned on, and declare the link invalid. So much for the inexpensive solution.
Correct, that's why the 5V line exists on an HDMI cable, to power that EDID chip in the "sink" or display.

That's also why items that are powered by that 5V bus are specifically non-compliant with HDMI's ATC standards - if something saps that power (like an equalizer/extender), then there may be little power left to activate and read the display's EDID chip, preventing the handshake from initializing, or causing intermittent dropouts.

Trent

We all know the reliability of many items on ebay, but I did find a 1:2 splitter with a price tag under $100 (it also is a "Submit Best Offer" item) I can't see any manufacture name anywhere so I can't find a history about it. If it works, I do believe that it's the cheapest one available...that's what scares me into placing an order though.

The listing can be found using the following search "2-Port Active HDMI Splitter / Multiplier w/power supply"

HDMI chips are not symmetrical, and can not simply be reversed. HDMI chips are clearly either a transmitter (meaning they send an encoded HDMI signal out), or a receiver (meaning they receive the encoded HDMI in). It's just not technically feasible to make a chip that can do both on the fly.

I just p/u the ConnectGear 1x2 powered splitter for my rptv and fp and so far so good. You can get it for around $100. It supports 1080p and HDCP devices.

Regards,
Ricky