We are often asked which HDMI splitter is “the best” and what the differences are. As you might have guessed, there is no “best” but there is definitely a better fit. All HDMI splitters distribute the signal from a playback device to 2 or more devices such as televisions and AVRs. By the way, a splitter with multiple signal inputs is called an HDMI matrix switch. The same applies to these devices. In addition to the fairly obvious differences such as connections, housing shape and controls, there are hidden features:

HDMI EDID management

When HDMI was developed it was assumed that it one HDMI source (media player or similar) and one HDMI sink (display or AVR). Over HDMI EDID The sink signals which image and sound formats are supported and the source delivers the optimal signal. Plug-and-play – that’s the theory.

If you now want to connect 2 displays to one source with a splitter, the two EDID information must be combined. The source can only a Process EDID record and only a Provide output signal. If both displays are the same, it's no problem. However, if the devices differ in possible image or sound format, the splitter must manage this.

And there are different approaches here. The following 3 modes simultaneously influence the EDID for audio and video signals:

COPY mode

In COPY mode, one of the connected HDMI sinks is prioritized. The player delivers exactly the same audio-video signal as when connected directly to this HDMI sink. One such main device is usually the television. A second device gets exactly the same signal (unless a 4K signal is scaled to Full HD, see below. For example, if the main device does not support DTS sound, DTS cannot be played. And if only the main device supports Dolby Digital sound, that leaves The second device is silent for Dolby Digital films

+ no restrictions on formats on the main device.

- Second device may have no picture or no sound

MIXED mode (also called AUTO)

In this mode, the properties of the connected HDMI sinks are compared. This generates an EDID that is supported by all HDMI sinks, the best common denominator, so to speak. This means that all devices receive a signal that they can play back. But it is not the best possible solution. For example, if a video projector and a television are operated in MIXED mode, surround sound is probably no longer possible because a projector only supports stereo (or no sound at all).

+ provides a compatible signal for all devices

- limits the maximum audio and video formats

STD mode

This mode provides artificial EDID information, regardless of what HDMI sinks are actually connected. The player can do 4K

+ can force the output of audio-video formats

- can produce incompatible signals, requires manual settings on the player

Audio EDID

In addition to these 3 modes, there is an approach to manage the EDID specifically for audio:

• 2.0 forces stereo output
• 5.1 forces output in stereo or 5.1 bitstream (AC3 Dolby Digital or DTS)
• PASS enables all audio formats supported by the audio HDMI device
• MIN is the best audio format supported by both sinks (and a commonly supported video format)
• MAX the best supported audio format ( and a commonly supported video format)

VSP01201 HDMI splitter

The VSP01201 and the 4-fold version VSP01401 have a slide switch for EDID mode. You can use this to control which output or display is prioritized. This is ideal if, for example, you have a 4K HDR source and a 4K HDR display and a second one without HDR support. This way you can ensure that a 4K HDR image can always be displayed, even if the second device does not support it. If you want to watch a 4K movie in Dolby Vision HDR, you should turn off a Full HD TV. The VSP01201 is primarily used if you want to operate 2 displays.

• In copy mode, provides an optimal format for display 1, even if display 2 cannot reproduce it correctly
• Ideal for connecting additional devices such as video grabbers, Ambilight converters and HDMI extenders
• Scales an Ultra HD signal to 1080p for a Full HD display 2

VSP01202 with audio EDID management

The VSP01202 only passes on HDR if both connected devices support HDR. This ensures that there is always an image. The VSP01202 is well suited if you want to watch on 2 displays at the same time. Or you can operate a TV with a soundbar and a video projector via the audio Min/Max switch allows you to set the EDID information for the sound format.

Min means: the best of both HDMI sinks supported format

Max means: the best format supported by one of the HDMI sinks (the second device may not be able to process the audio format)

Max is well suited if there is a sound system on your main device. Min if the devices are in 2 different rooms and both require sound.

• Ensures optimal audio format regardless of display
• Scales an Ultra HD signal to 1080p for a Full HD display on the second output

VSP01203 with Audio Extractor

At the VSP01203 There are 2 EDID modes: At Copy the splitter behaves “invisible” to the source. This means that a display is prioritized and the output depends only on its capabilities. However, you can manually set whether the other displays should be scaled from 4K to 1080p. In mode The best commonly supported format is automatically delivered - all active devices receive a usable signal. In addition, with this splitter the sound can be delivered independently to active speakers or a surround system via a light guide or stereo audio cable.

• In copy mode, provides an optimal format for display 1, even if display 2 cannot reproduce it correctly
• If desired, scales an Ultra HD signal to 1080p
• The sound also delivers sound to a sound system or headphones via SPDIF and 3.5 mm jack

VSP01204 with HDMI pigtail

The VSP01204 Splitter is ideal for connecting to 2 similar screens. The splitter has a short HDMI cable breakout (also called pigtail) at the input, so cabling is minimal. An external power supply is usually not required (but possible via USB). A format is always output that both screens can process equally. Typical application: Connection to 2 identical monitors, or an Ultra HD and a Full HD television. (Note: It is not possible with any splitter to display 2 different screens as an "extended desktop" from the PC. This only works if the graphics card already has 2 outputs.)

• Ensures the best possible output format for both displays
• Scales an Ultra HD signal to 1080p for a Full HD display 2
• Can be operated without a power supply/power supply

VAX01203 for a surround system

We have the VAX01203 HDMI splitter specifically designed for distribution to a 4k video projector (or monitor or television) and a surround system. A Full HD signal is always sent at the second HDMI output. Advantage: Older sound systems that cannot process 4K signals can also cope with this. At the same time, specific audio formats can be selected using the EDID switch: 2.0 for stereo, 5.1 up to Dolby Digital Plus and 7.1 for Dolby TrueHd, Dolby Atmos, DTS-HD.

• Delivers optimal image for the display and maximum sound formats for the sound system via HDMI
• Ideal for connecting to a 4K projector/TV and a high-quality AV receiver (can also be older!)
• Bypasses audio restrictions on the display and enables, for example, DTS sound on current televisions or Atmos with a projector
• Parallel output also possible via jack (stereo) and Toslink (up to 5.1).

Other differences

The VSP01201, VSP01202 and VSP01222 largely support HDMI-CEC on one output. This allows you, for example, to control the basic functions of the media player with the television remote control. Please note, however, that CEC is only activated on one TV in the HDMI chain. CEC doesn't allow anything more!

The VSP01222 also has an HDMI-ARC pass and is therefore ideal for operation at the output of an AVR, e.g. for TVs and projectors. With ARC Pass, the internal TV sound from apps or tuners can also be played back by the AVR. become.

Downscalers

All of our HDMI splitters support downscaling. When a 4k Ultra HD signal arrives, the splitter downscales (scales) it to 1080p for a connected Full HD display - without any significant loss of quality and without any time delay. For most HDMI sources, the prerequisite is that at least one of the connected displays also supports 4K.

Scaling is also the only intervention in the signal that the splitter can perform. Otherwise, the splitter can only manage the EDID information so that the source outputs the desired signal and then distribute it. It would be desirable if every display received the best possible signal. Unfortunately, this is not technically possible. For example, the HDMI source cannot output stereo sound and 5.1 sound at the same time. Not even 4k Dolby Vision and Full HD SDR at the same time. Unfortunately, the topic is complicated due to the additional technical limitations of the respective interface generation (HDMI versions).

Special case Dolby Vision and video projector

Please note that Full HD devices correctly display a downscaled 4K signal in SDR, HLG-HDR or HDR10. But if the output signal is in Dolby Vision or HDR10+ format, the colors will be completely incorrect. There are hardly any video projectors that support Dolby Vision, but most current televisions can. Here you either have to manually switch off Dolby Vision on the player if you want to watch on the projector. Or as a compromise, permanently set the output to HDR10. If you don't use internal TV apps and have all Dolby Vision content played externally, it can be quite annoying. Unfortunately, it is very time-consuming to have Dolby Vision removed from the signal. A normal splitter lacks the computing power to do this.

3D video

Current televisions no longer support 3D video. If the output for an Ultra HD television is prioritized, 3D is not possible on the second device. If you want to watch 3D on a Full HD display instead, this must be prioritized and operated in EDID COPY mode. Then 4K no longer works. Special firmware is available for the matrix switches VMS04201 and VMS04400 that enables 4K and 3D at the same time.

HDMI 2.1 splitter

With splitters for HDMI 2.1, which transmit signals from the latest game consoles, there are additional challenges if an HDMI 2.0 sink is also to be operated. It is possible to scale a 4K 120Hz signal for the second device so that it is output in Full HD 120Hz. Some HDMI 2.0 devices can still handle this (but many cannot). What doesn't work at all on HDMI 2.0 are variable frame rates (VRR).

Note on sound bars

Unfortunately, it is poorly explained for many soundbars and seems illogical to many users: The HDMI-ARC or HDMI-eARC connection on a soundbar functions as an audio input, but is an HDMI output ! Therefore, no HDMI output of a splitter can be connected or operated. Splitting the signal for this is only possible if the soundbar has one or more additional “real” HDMI inputs. ARC means audio return channel and the signal direction is reversed to the normal path. Therefore, the HDMi-ARC connection on the soundbar is also connected to an HDMI input on the television.