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Old 08-19-2013, 03:05 PM - Thread Starter
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Good morning AV gurus

Here is the scenario:

A bluray is streaming 5.1 stereo via a matrix switch to a receiver thence to a projector - all good

Another zone joins the bluray session via the matrix switch and displays on a TV and separate stereo system. - all good

BUT

The 5.1 in the theatre now switches to stereo too.

At no time are audio or video streams actually connected to two differing sink devices directly. They are effectively "isolated via the matrix switch.

So my questions are:

Is this normal behaviour for multiply connected/distributed HDMI selected via a matrix switch (particularly when the switch costs $10k !!!)?
Could this be the result of a poorly designed matrix switch?
Might it be the bluray that is changing its codec and would "locking" it to a single codec be a solution (If this is even possible)?
What component is likely to be making the decision to downscale to the "weakest" audio stream and why should it care at all?

That said...

Can anyone see a way by which multiple zones can join a bluray (or NAS) movie session without each affecting each other.
Would an Atlona EDID read/writer be a way around this perhaps?



The equipment list is any of: Marantz receivers and blurays coupled with Leaf matrix switches


Any advice or help would be much appreciated.


Karl
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Old 08-19-2013, 03:25 PM
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Not sure about ‘A bluray is streaming 5.1 stereo’ – the Player is either doing 2.0 (stereo) or 5.1 not both at the same time via a single HDMI port!

If you are Outputting Video + 5.1 via HDMI and you have differing capabilities at your multiple Sinks (TV, AVR, etc.) your Source will either play on regardless and you will hear audio in some zones but not others or the Source will stop what it is doing and reset to a signal it knows all Sinks support – potentially limiting you to 2.0 in all Zones

How you ‘work’ around that ‘designed in’ behaviour of HDMI can take many forms.

Joe

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Old 08-19-2013, 04:16 PM
 
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Quote:
Originally Posted by physics prof View Post

Good morning AV gurus

Here is the scenario:

A bluray is streaming 5.1 stereo via a matrix switch to a receiver thence to a projector - all good

Another zone joins the bluray session via the matrix switch and displays on a TV and separate stereo system. - all good

BUT

The 5.1 in the theatre now switches to stereo too.

At no time are audio or video streams actually connected to two differing sink devices directly. They are effectively "isolated via the matrix switch.

So my questions are:

Is this normal behaviour for multiply connected/distributed HDMI selected via a matrix switch (particularly when the switch costs $10k !!!)?
Could this be the result of a poorly designed matrix switch?
Might it be the bluray that is changing its codec and would "locking" it to a single codec be a solution (If this is even possible)?
What component is likely to be making the decision to downscale to the "weakest" audio stream and why should it care at all?

That said...

Can anyone see a way by which multiple zones can join a bluray (or NAS) movie session without each affecting each other.
Would an Atlona EDID read/writer be a way around this perhaps?



The equipment list is any of: Marantz receivers and blurays coupled with Leaf matrix switches


Any advice or help would be much appreciated.


Karl

First, Joe is right, there is no such thing as "5.1 stereo". So I'm going to assume you mean 5.1 and then the 5.1 gets "downgraded" to stereo later on.

If so, this is just standard EDID behavior with a matrix switch with no EDID spoofing. There is no such thing as isolating a sink with most (maybe all) matrix switches that don't do something outside of the spec.

So, you could spoof the EDID to force a 5.1-channel output. But, then any sink that can't handle 5.1 will not produce any audio.

What you should always remember is that HDMI only has one video and one audio stream at any time. If you want more than 1 (such as 5.1 *and* stereo at the same time), then it's not something HDMI can do.

The other thing you should also be aware of is that every matrix switch I've tried blanks the screen of all sinks when one sink is put into standby. If I turn off screen 1, then screen 2 will momentarily blank. It's annoying.

I believe Joe can provide you some choices in the Octava line that can handle 5.1-channel spoofing.
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Old 08-20-2013, 03:26 AM - Thread Starter
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Ooooops My bad!!

Should not have said 5.1 stereo. Just 5.1

Thanks Joe for your reply and to you alk3997 smile.gif


I guess this is the reality of trying to stream 1 source to multiple disparate sinks and it simply "aint gonna work" easily.

The Octava switch may be worth considering (I see their web URL has gone which doesnt bode well).
We are looking at the new generation of hydarconnect top end switches which allow CEC control and interface directly with Control4.

I am considering installing HDMI pass through boxes with an audio stripper - may do the trick?

Anyway, thanks for your prompt replies. Has given me heaps to ponder


regards

Karl
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Old 08-20-2013, 03:35 AM
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Hello Karl

Which Octava URL are you having problems with - wasn’t aware we had a problem on any of our pages?

Control4 - any device with an RS232 port will work with C4, we have plenty of Octava customers integrating them with C4.

How you manage your audio will depend on where you want to spend the money to achieve a mix of 2.0, 5.1 and 7.1 in different Zones - maybe outline what you are wanting to achieve and folk will suggest a solution.

Joe

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Old 08-20-2013, 09:23 PM
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Joe let me know that the Octavia switchers do not blank during switching and true high end switchers from AMX, Crestron, and Extron definitely do not blank during switching.

Crestron I know offers HDMI switchers which include audio DSP integrated so you can pass HD audio to your A/V receiver, while passing stereo audio to a TV, while passing stereo audio to a amplifier, and surround to a different receiver. They are pricey, but can be IP controlled for integration into any system that you may want to use. We have used them with AMX as well as Crestron systems so far. From what we have seen, they are the most fully implemented HDMI top shelf matrix switcher on the market so far. With a matching price tag of course.

It still really isn't clear what you are trying to accomplish I must say. But, a cheap HDMI switcher connected to any TV directly will recognize the TV as a stereo sink and will downgrade audio to stereo. So, it's really important if you want to force HD audio to use a EDID management system which will force the audio to the level you would like. This takes good design practice and thought to implement properly.

AV Integrated - Theater, whole house audio, and technology installation in the Washington DC metro area.
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Old 08-21-2013, 10:05 PM - Thread Starter
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Hi guys

Thanks for all the feedback and information

We are a top-end integrator and money for top-end equipment is not an issue. It is a matter of choosing the right matrix switch for avoid connectivity problems.
We also want to stay with one brand to avoid going over the same problems in a "groung - hog day" scenario.

A typical configuration is a $40k Theatre with 5.1 as the primary zone with up to 8 other stereo zones joining in at will. It is essential that those "dumbed down" zones don't drag the Theatre down too.

We were considering the hydraconnect switch because of its intrinsic high quality and its CEC command system which offers a lot of appeal because IR driver code issues are too time consuming and an ongoing source of control issues for us. The Octavia AMX, Crestron, and Extron switches may well offer a similar solution. will have to do a bit of reading.

thanks again guys

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Old 08-23-2013, 09:35 PM
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We use Crestron, AMX, and Extron in our company and at the moment Crestron is leading the pack as they are on, more or less, their 5th+ generation of HDMI matrixing. They have included a CEC capable engine for years, but offer remote extenders with RS232 control as HDMI CEC is pretty much worthless as it has been implemented.

It also gives you an all-in-one solution with a configurable chassis that currently runs up to 32x32 with reports of a 64x64 frame being out around the end of the year.

Things I like:
HDMI input card with integrated DSP so if you have analog stereo zones to feed, it can be fed from a HD audio source, into the HDMI matrix, and retain HD audio while simultaneously delivering a 2-channel downmix for the audio distribution.
Zero blanking as more displays, sources, etc. are turned on/off across the system. This is a huge issue with mid-grade and lower systems which will blank displays as HDCP is renegotiated. It is a non-issue in the Crestron, AMX, and Extron world.
Scaling receivers... In a 1080p world, there are still some lower resolution displays that pop up and the scaling receivers allow you to ensure an accepted resolution makes it to the final destination.
EDID management... If you don't know what this is, you should. In fact, for proper HDMI implementation across a top dollar installation, some level of EDID management is basically a must.

On top of that, they have a 3-year warranty on their stuff and have a history that is decades old with current support on products which are 10+ years old.

I swear by AMX and Extron as well, but at the moment, Crestron is just a step ahead of others.

They aren't inexpensive, but are similarly priced to the other top dogs (AMX/Extron).

AV Integrated - Theater, whole house audio, and technology installation in the Washington DC metro area.
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