Extract audio & image from a PC --> 4 TVs + amp + speakers




I'll open soon a small fitness center in France, and here is my installation:
- 2 x 75'' LED TVs at left of the room with 2 x Martin speaker and 1 Martin sub.
- 2 x 75'' LED TVs at right of the room with 2 x Martin speaker and 1 Martin sub.

Only videoclips will be played on the 4 TVs. The TV will always play the same thing at same moment. The synchronisation must be perfect between the 4 TVs, and of course, with the audio. The DSP Martin DX0.5 will allow, I think, to manage the delay between the sound and the image, I'll tune it once and for all.

All will be controled by my PC, with Windows 10.

My problem is that I don't know at all how to do with my PC.
- my mothercard is a "Gigabyte B360 HD3"
- my graphic card is "Gigabyte GeForce RTX 2060 Windforce OC 6Gb"

What I want to do is splitting my PC monitor in two: on the left part of the monitor, I want to see my normal desktop (to check my e-mail, control my .mp4 playlist, etc.), and on the right part, I want to see the videos, exactly what my clients will see. Of course, I never want that my clients see the mouse pointer, texts, etc., I don't want that they see what I'm doing: only videos for hours and hours.

Splitting my PC monitor like that is possible?

Am I right about these connexions?
- PC monitor plugged to the Graphic Card DisplayPort.
- HDMI Bluestream splitter plugged to the Graphic Card HDMI port.
- Focusrite plugged to the Motherboard green sound Realtek output?

The resolution of my videoclips will be all different, sometimes 1080p, sometimes 720p, maybe 4K. Is it possible with my playlist that all is automatic and that the image size automatically adapt to my 75'' TVs?

Thanks so much for the help, I'm really lost in that last step of my project! :)

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Audioholic Warlord
There is a lot you are asking for and most of these things are based upon computer settings and not much else. It also uses equipment which isn't typical or common for the average home user to do. And, of course, you are trying to do it on something of a budget.

We have no idea what kind of TVs or speakers you will really be using. It actually helps to list the model number. Kind of like saying "I will be racing a Chevrolet against a Volkwagen... Will I win?" You need to provide far more in the way of specifics to get a real answer.

That said, assuming the DSP from Martin does a good job with internal crossover settings and the like, I wouldn't expect any issues in audio delivery to the speakers.

Video will be output from the graphics card, most typically as 'monitor 2' from the PC. This means that whatever shows up on Monitor 2 will show up everywhere, including if you drag your mouse onto monitor 2. If you have software which supports multiple monitors, including a management piece of software and a playback piece of software, than that software may allow you to control things without interuption.

Your monitor 2 should match the same resolution of the TVs. Do not get a 1080p monitor if your displays are 4K and you are setting the system up for 4K content delivery.

Be aware that you are making a separate physical connection for these two monitors. Monitor 1 is connected to the graphics card on one of the DisplayPort connections.
Your second monitor and ALL THE DISPLAYS will be connected to the HDMI output of the graphics card, and should be sent through a splitter that supports 5+ video outputs.

Assuming this is the product you are talking about...

By the looks of things, this all seems like a reasonable setup.

Make DARN SURE - you are using 18Gb/s HDMI cables from your splitter to the displays if your end-goal is 4K video.

The computer will automatically scale the source material to 4K for playback if that's what you have the PC set to push out. If you set the computer to push out 1080p video, then that's what you will get. The EDID minder in the Bluestream HDMI splitter will help you set that resolution, but you can right click on your Windows Desktop and set that resolution as you choose.

All this said: I would recommend that you consider getting a digital signage player. Products like Brightsign (from Roku), are designed to act as stand-alone player devices that have schedules, playlists, and more which can be setup, configured, changed, etc., while they are playing back video, information, music, etc. without interuption. There are a ton of different players on the market, and they all have a bit of a learning curve. But, once you are comfortable with it, you can update a playlist on the fly while the player just keeps doing its thing. This gets you away from a Windows PC which will go down as software updates occur, and windowing and lockups can occur as well as other problems. Dedicated signage players are for exactly the type of situation you are currently in.

If you need audio out of a signage player which doesn't have audio out, then you can get a HDMI audio extractor.
Brightsign players have several 4K models which have included analog audio output and are just a few hundred bucks.
I will remind you that there is a learning curve with these models and they aren't always drag-and-drop easy to setup.


Wow, thank you so much for this so interesting answer. All seems clear, but I still have a doubt about sound extraction.

What is the best solution to extract sound (ampli will treat the delay with image) with the best sound quality possible:

A) Directly from the computer with a Focusrite (USB) ?

B) From the audio output of the Bluestream HDBaseT splitter (in that case, 2 options: digital coaxial OR analog L/R) ?

Some shops told me that A) was better than B), and other than B) was better than A)...

Thanks a lot! :)




Audioholic Warlord
I certainly wouldn't use the Focusrite in this setup. Either use the onboard computer audio output, which is already there. Or use the audio output from the Blustream product. Adding a external USB to analog device is just another product to go wrong for no obvious reason. It is also a product which could be added later if you so desired.

The HDBT Tx unit will need matching receivers at all of the TVs if that is the plan.

You will also have to solidify your exact video format before you get too far along. 4K video, while it can look nice, can be very problematic for video distribution. So, walk down that road carefully. The local 'loop out' of the HDMI signal from the Blustream HSP14CS is a nice feature that I approve of as well. It will give you that local monitor feed which can show you locally exactly what is going to all of the other displays in the setup.

So, if the plan is 4K/60, then you will need to get four of these for the TV locations...

I think that you may find that having a PC run the show instead of a dedicated signage player may not be the best end game, but with this setup you can drop whatever source you want in front of the Blustream and it should handle all of it without issue.

I'm not familiar with the UK brands that you are working with, so I can't speak to their quality or reliability overall. I tend to work with a lot of QSC, Biamp, Extron, and Crestron product in the USA. But, the Blustream stuff seems straightforward enough. I've heard of Martin, but I'm not sure their price/value proposition, which is something I often consider. I mean, this is a pretty basic DSP setup. No phone lines or microphones appear to be going into this setup, so just mixing and some delays and crossovers.

I'm a cheap guy, so I would jump on eBay and pick up a Biamp Tesira Forte (used) which has 12 analog audio inputs and 8 analog audio outputs. It also has integrated USB connectivity to connect a PC directly to it with USB, so no need for an external controller unit.

Something like this for about $300 is a heck of a deal on a $2,000+ product...

I would expect the quality of the Biamp to match or exceed the Martin. Plus, the added audio inputs may give you some flexibility down the line, even if you aren't using them right away.

I would likely do the same with my amplifiers. Pick up a couple of decent used Crown or QSC amplifiers...

I would stick with new TVs and new speakers, but amplifiers can last decades without problems, as can DSP units.


Thanks you so so much for your so interesting answer! I'll follow your instructions....

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