HDMI splitter

HDMI 1x2, 1x4 Splitter

1) It is HDMI V1.3 top Spec of 10.2Gbps, with HDMI V1.3, you get Higher Resolution, Higher Frame Rate, Deeper Colors.

Since there are so many HDMI V1.2 or older products were "mis-labeled" to V1.3, it is wise for buyers to be skeptical and dig further into product data. The only way to identify whether a HDMI product is true V1.3 or not, is to check whether it meets V1.3 speed requirements. HDMI V1.3 bandwidth is 10.2Gbps, which requires a video amplifier frequency of 340MHz to achieve it. HDMI V1.2 is 4.95Gbps or 165MHz. So, if you see a "V1.3" HDMI product having a video amplifier frequency of 165MHz, then you won't be misled.

2) The splitter has independent outputs, when the two outputs connects to two TVs, you can watch one TV and shut down the other TV. Early generation splitter has "synchronized" outputs, which means both TVs have to be on at the same time, even if you only need to watch one.

3) It supports all the HD Audio formats, DTS-HD, Doubly-TrueHD... along with deep color up to 36-bit for advanced video.

To enjoy all of its state of the art capabilities, basic understandings of how the HDMI splitter works is required to fully utilize the capabilities of your audio and video equipments.

HDMI Splitter Fundamentals:

1) HDMI Splitter doesn't change/modify HDMI signal format. The HDMI signal format (video & audio) is determined by the HDMI A/V unit at the splitter input.

2) When only one of the two TVs at the two splitter outputs is on, for example: the A/V source is a blu-ray, display is a 1080P TV. Then the HDMI signal (containing audio and video streams together) will be running at 1080P, the audio will be the highest audio format supported by the TV.

3) But if a splitter is of poor quality, having trouble passing 1080P signal, then the 1080P signal will be degraded (signal quality, not signal format). This downgrade is not automatic, if you can't get 1080P picture on your TV, then you need to force the resolution lower until you get a acceptable picture, this is likely to happen in application of extra long wires, or HDMI repeater / extender that can't support 1080P. The signature of poor cabling is snowy picture.

4) When both TVs are on, the blu-ray will only supply the commonly acceptable A/V format for both TVs. For example, if one TV is 1080P, and the other is 1080i, the signal format will then be at 1080i, so both TVs can work properly. For this splitter in such 2 TV setup, you can shut down the 1080i TV to watch 1080P TV at 1080P. (If you are using the older generation splitter, then you have to remove that splitter to watch the 1080P TV at 1080P, because the other 1080i TV has to be on and it will keep the format at 1080i if you running the signal through that splitter. What a waste of resource!)

5) Example of incorrect setup: some user connects blu-ray to the splitter input, connects one output to TV, and the other output to surround receiver, then complains that the splitter doesn't support advanced audio. This is not the fault of the splitter, this is what it supposes to be. Because in such configuration, the audio format is limited by TV, because both TV and the receiver have to understand the same audio stream, the blu-ray will provide the basic audio stream understood by the TV, regardless how advanced the audio of your receiver and blu-ray disc are capable of. All the decisions are made by the HDMI unit at the splitter input, the HDMI splitter has nothing to do with A/V format received by TV or receiver.

This setup (one output goes receiver, and the other output goes to display unit) is good, if the display is a display only unit without audio capability, such as a projector, becuase if a display unit without audio, then it should not request audio support, so the video source only needs to take care of the receiver audio request, will make this work.

(Referring to the negative review on this item: You can not "split the picture one way and then split the sound the other", because when the two outputs are on, the HDMI data stream at the two outputs are exactly the same. The splitter's job is to generate two output signals as good as the single input signal. The HDMI splitter is not responsible for the Video or Audio format you get at the TV or receiver, those are determined by your A/V source unit per HDMI protocol. You actually wrote a review of your incorrect setup of A/V configuration and the resulting poor performance, instead of a review of this splitter.)

The right product for such applicatin is:

6) To enjoy HD / Advanced Audio, the correct setup configuration is: blu-ray to receiver to HDMI splitter to TVs. So that the HD Audio format can be determined by (receiver + blu-ray + disc) and the video format can be determined by (TV + blu-ray), (audio is taken care by receiver, and video is by TV) thus avoiding audio format to be limited by TV audio capability. Such configuration enables the enjoyment of the best of both worlds: Video and Audio.

7) If you use a computer as the A/V source into the splitter and the splitter outputs go to say one TV and one monitor. Since the computer output video is typically forced to an user defined resolution, so you need to make sure that this video resolution is commonly acceptable to both the TV and the other monitor, otherwise, one of them or even both of them may not have picture.

8) If your TV doesn't display picture after installing the splitter, it may be that your A/V source unit or old TV has HDCP problem, the HDCP authentication check fails, please use other A/V source or newer TV to verify this.

9) The output light status: When the output light is RED, it means the video content is not HDCP protected material; when the output light is BLUE, it means the content is HDCP protected. When there is no light, the output is not active.

Buy this genuine line of products from the original manufacture, avoid the copies; more importantly to avoid the sellers selling the copies.

+++ Setup Example Case #1 +++

When using the 1x2 splitter to support two TVs with different resolution, say first one at 1080P and second one at 720P. In the case of a significant routing difference between this two TVs, say one TV is 8FT away from the splitter, and the other TV is 35FT away, then it is recommended to place the higher resolution 1080P TV at 8FT away and the 720P TV at 35FT away. This could avoid potential problem in case the 35FT HDMI line can't support 1080P, but CAN support 720P. In this case, if the setup is opposite, then you will get pictures on both TVs when both TVs are on at the same time, but when the 720P TV at 8FT away is turned off, the 1080P TV at 35FT away may not have picture if the 35FT line can't carry 1080P due to the insufficient quality of cable and signal loss over a long line.

+++ Trouble Shooting Case #2 +++

We have seen one case using this splitter for two TVs, one is a new 1080P and one is an old 720P. Both TVs have picture without this splitter, but when using this splitter, only the 1080P TV has picture, but the 720P TV doesn't. Then we found out that when video format from the source unit is forced to 480P, 720P, 1080i, and 1080P, the 1080P TV always has picture, but the 720P TV only has picture when the video format is forced to 480P. This is a classic case that the 720P TV is having HDCP (High Definition Content Protection) compliant issue. It fails the HDCP 1.2 check performed by this splitter. Therefore, any video format beyond 480P will not be shown correctly / no picture on the older 720P TV, while the newer 1080P TV is fine. This is not a splitter problem, the older 720P TV needs a HDCP firmware upgrade to solve this problem. If the TV indeed has HDCP, then it will be a compatibility issue (please refer to HDMI handshake in the later part)

+++++ Trouble Shooting Case #3 +++++

We have one customer using the ViewHD 1x4 splitter (and the case applies to ViewHD 1x2 as well)with three TVs (Samsung LN-T5271F, Toshiba 47HL167, and a Toshiba 40RV525R). The problem is between Samsung LN-T5271F and Toshiba 40RV525R. When she turns on/off the Toshiba TV, it would also turn on/off her Samsung TV downstairs. If she disconnects this HDMI splitter between the two TVs, the turn on/off problem would not occur.

This problem is introduced by TV with the CEC function. "Consumer Electronics Control (CEC) wiring is mandatory, although implementation of CEC in a product is optional. CEC uses the industry-standard AV Link protocol, is used for remote control functions, is a one-wire bidirectional serial bus, and was defined in HDMI Specification 1.0 and updated in HDMI 1.2, HDMI 1.2a, and HDMI 1.3a (added timer and audio commands). The CEC feature is designed to allow user to command and control multiple CEC-enabled boxes with one remote control and for individual CEC-enabled devices to command and control each other without user intervention.

Alternative names for CEC are Anynet (Samsung); Aquos Link (Sharp); BRAVIA Theater Sync (Sony); Kuro Link (Pioneer); CE-Link and Regza Link (Toshiba); RIHD (Remote Interactive over HDMI) (Onkyo); Simplink (LG); HDAVI Control, EZ-Sync, and VIERA Link (Panasonic); EasyLink (Philips); and NetCommand for HDMI (Mitsubishi)"

The problem can be easily fixed by disabling the HDTV's CEC function.

+++ Regarding HDMI Handshake +++

Many people may have misunderstanding regarding the HDMI handshake. HDMI splitter introduces a HDMI handshake situation beyond the normal two party handshake; splitter introduces the problem, but it is not the cause of the problem. The cause is the video source can't deliver a perfect solution that is good to everyone AT THE SAME TIME.

HDMI handshake is done by video source using EDID link between display units and video source, NOT by the splitter.

The splitter first checks HDCP, and then the splitter becomes an open highway for communication between display units and the video source unit. The EDID communication between display units and the video source provides video source the video and audio capability info of the components connected to the splitter outputs, then video source will make the best judgement and send out the best video and audio format suitable for ALL. But due to the compatibility issues (rare but exist), some setup combinations will not work, one TV has picture, the other may not.

For example, Samsung LN52A650A LCD TV will not work correctly together with Hitachi L42S503 LCD TV, in a splitter setup, even though both are 1080P units, but they work perfectly in one to one case.

To identify handshake issue, first test the one to one case, connect only one TV to the splitter output AND DISCONNECT all other splitter outputs, power down other TVs or even unplug the other TVs may NOT be sufficient, because different TVs have different HDMI interface implementation, so please DON'T MAKE ASSUMPTIONS when doing this test.

The splitter should ALWAYS work in one active output case (one to one), as long as it works if without the splitter in between. If a splitter can't do this (as a single output repeater), it is a defective splitter. Check all outputs one by one, all outputs of a splitter should work identically, if not, it is a defective splitter. If a splitter works perfectly in one active output case, but not working correctly when there are more active outputs, then there is very likely to be compatibility issue, somehow the combination of the displays and video source make it difficult or impossible for the video source unit to come up with a decision to deliver a commonly acceptable A/V format good for all units connecting to the outputs of the splitter. Splitter has nothing to do with this decision made by the video source, it only introduces this more complicated situation, and all it does is to make multiple copies of the input data stream and feed them to all the active outputs. The only benchmark to measure HDMI splitter is the signal quality it duplicates, the output signal should be as good as the input signal.

A few negative reviews here (promoting the HDMI A/B mechanism switch) because the buyers faced the compatibility issues, and blamed on the splitter. They assumed that if they turned off other TVs and only had one TV on, there should not have multi-party (>2) HDMI handshake problem, so when it didn't work, they blamed on the splitter. The fact is, this is case by case depends on how the HDMI input switch was implemented on the display unit that was "powered off". Some display unit when power off, the display is off alright, but its HDMI input switch is still hot/standby and EDID checks continues, so the video source never knows there is setup changes and no need to take care of the power off unit any more, in such case, power off the display doesn't do anything to the existing HDMI configuration. There is also some TVs/Projectors, even when the unit is completely unplugged from the power outlet, their presents can still be maintained, because the HDMI cable connecting the splitter and the display unit can provide power to power up the HDMI input switch of the display unit, and make it appears to be active (many HDMI switches are powered in this way). Therefore, to avoid confusion/frustration, please make sure to DISCONNECT the CABLE for this test to find out the true cause of the problem.

A HDMI splitter is to provide the same A/V signal to multiple outputs at the same time, thus introducing multi-party (>2) HDMI protocal, it will reveal possible compatibility issues, which the one video source to one display case will never encounter. A HDMI mechanical A/B switch will direct the input to either output A OR output B, only supporting one TV at a time, therefore avoid possible compatibility issues. Bashing a splitter and prasing A/B switch is comparing apple to orange, they are differet products serving different needs.

What is EDID?

EDID stands for Extended Display Information Data. This is the data contained (usually in a small EEPROM) on each DVI display or HDMI sink. There may be as many as one EDID per DVI or HDMI input.

The source device checks the display's DVI or HDMI port for the presence of an EDID prom and uses the information inside to optimize the output video and/or audio format. The EDID data structure can be for either VESA PC devices or for CEA-861B E-EDID (Enhanced EDID) devices. All sink devices compliant to the DVI or HDMI specification must implement EDID.

An EDID PROM is used only in sink devices. An EDID PROM sits on the DDC channel and uses a 2-wire I2C bus (part of the DDC specification from to communicate from the sink to the source. The EDID PROM contains information about the sink that it resides in. Its job is to communicate the preferred (or supported) video and audio formats and resolutions to the originating source. As an example, when a DVD player is powered on, it reads the EDID from an attached HDTV. The HDTV will have in its EDID contents that it is a Samsung 17" LCD panel that supports native resolution of 1280x1024 pixels, but can also support 480p, 720p and 1080i video modes. The EDID may also say that the TV is an HDMI device and has 2-speakers. The DVD player would compare this information with what it can put out of its HDMI port, then set itself to send 1080i with 2-channel stereo to the HDT