BK-104 Overview and Use Cases

What Is the BK-104?

The OREI BK-104 is a 48Gbps 1x4 HDMI 2.1 splitter. It takes one HDMI source and duplicates the same audio/video signal to up to four HDMI displays at the same time.

The HDMI source connects to HDMI IN, and up to four TVs, monitors, projectors, or displays connect to HDMI OUT 1 through HDMI OUT 4.

The BK-104 supports HDMI 2.1, HDCP 2.3, video bandwidth up to 48Gbps, resolutions up to 8K@60Hz 4:2:0 12-bit and 4K@120Hz 4:4:4 12-bit, HDR, HDR10, HDR10+, Dolby Vision, HLG, VRR, ALLM, QMS, QFT, SBTM, advanced EDID management, automatic downscaling, HDR-to-SDR conversion, and HDMI audio pass-through including Dolby Atmos and DTS:X. The manual’s application example shows one DVD or Blu-ray player connected to HDMI IN and multiple 8K TVs connected through the HDMI outputs.

The BK-104 is useful for 8K TVs, 4K@120Hz gaming displays, home theaters, AV receivers, game consoles, Blu-ray players, conference rooms, digital signage, and commercial AV installations where one HDMI source needs to be shown on up to four displays.

IMPORTANT — BK-104 Is a 1x4 HDMI Splitter

The BK-104 duplicates one HDMI source to four HDMI outputs.

This product mirrors one HDMI source. It does not create independent video outputs and does not extend a PC desktop across four screens.

IMPORTANT — Supports 8K@60Hz and 4K@120Hz

The BK-104 supports high-bandwidth HDMI 2.1 video formats.

To get 8K@60Hz or 4K@120Hz, the HDMI source, HDMI cables, connected displays, and selected EDID mode must all support the required signal.

IMPORTANT — HDMI 2.1 Gaming Features

The BK-104 supports several HDMI 2.1 gaming and video features.

These features depend on the HDMI source, game console or PC, display, HDMI cable, and EDID setting.

IMPORTANT — Automatic Downscaling Is Supported

The BK-104 supports automatic downscaling on all outputs.

It can downscale:

1. 8K to 4K
2. 8K to 1080p
3. 4K to 1080p 
    
   Before downscaling, the splitter compares the EDID information from connected displays and selects the minimum resolution needed to downscale and output.

IMPORTANT — Automatic HDR-to-SDR Conversion Is Supported

The BK-104 supports automatic HDR-to-SDR conversion on all outputs.

This is useful when one display supports HDR and another display only supports SDR.

Auto Downscaling and Conversion Examples

The manual shows examples of how the BK-104 handles mixed display setups.

The manual also notes that if the source is downscaled and converted to 1080p DVI according to the display EDID, that output will not have sound.

IMPORTANT — DVI Output Has No Sound

If the BK-104 converts the signal to 1080p DVI based on a connected display’s EDID, that output will not carry sound.

This is expected because DVI does not carry HDMI audio.

If a TV unexpectedly receives DVI output:

1. Try a different HDMI input on the TV
2. Replace the HDMI cable
3. Restart the source and splitter
4. Try a different EDID setting
5. Confirm the display reports HDMI audio support

Advanced EDID Management

The BK-104 includes a three-position EDID DIP switch with eight settings.

A switch in the UP position represents 1. 
A switch in the DOWN position represents 0.

Understanding Copy OUT 1 EDID Mode

DIP code 111 copies the EDID from the display connected to HDMI OUT 1. This is the factory-default setting.

Use this mode when:

1. HDMI OUT 1 is connected to the primary display
2. The source should follow the main display’s capability
3. The main display supports the desired resolution and audio format
4. You want the splitter to automatically negotiate based on OUT 1 
    
   If the other displays have lower capability, automatic downscaling and HDR-to-SDR conversion may adjust their output.

Selecting an EDID Mode

The manual does not provide additional guidance for choosing between FRL12G and FRL10G. Use the setting that is compatible with your HDMI source, displays, and HDMI cables.

After changing EDID, restart or reconnect the HDMI source if it does not renegotiate automatically.

IMPORTANT — This Is Not an Audio Extractor

The BK-104 passes HDMI audio through the HDMI outputs, but it does not provide separate audio extraction ports.

Use a dedicated HDMI audio extractor, AV receiver, or splitter with audio extraction if separate audio output is needed.

Supported HDMI Audio

The BK-104 supports HDMI audio pass-through formats including:

The selected EDID setting determines whether the source outputs 2.0CH, 5.1CH, or 7.1CH audio.

Ports and Panel Layout

Step-by-Step Setup

1. Connect the HDMI source device to HDMI IN on the BK-104. 
   Examples include a Blu-ray player, game console, streaming device, cable box, satellite receiver, desktop PC, laptop, DVR, NVR, or media player.
2. Connect the main display to HDMI OUT 1.
3. Connect HDMI OUT 2, HDMI OUT 3, and HDMI OUT 4 to additional displays as needed.
4. Set the EDID DIP switch.
5. For default EDID behavior, use DIP code 111.
6. Connect the included DC 5V/2A power adapter.
7. Power on the HDMI source, displays, and splitter.
8. Check that the Power LED is on.
9. Check the IN LED to confirm the source is detected.
10. Check OUT 1–4 LEDs to confirm connected displays are detected.
11. Test video, refresh rate, HDR/SDR behavior, and HDMI audio on all connected displays.

HDMI Cable Requirement — Critical

Use the correct HDMI cable for the resolution being used.

For 8K and 4K@120Hz, use certified Ultra High Speed HDMI cables.

Poor or unsuitable HDMI cables may cause:

1. No video
2. Flickering
3. Black screen
4. One output not working
5. 8K@60Hz not working
6. 4K@120Hz not working
7. HDR issues
8. VRR issues
9. HDCP handshake issues
10. Audio dropouts 
     
    For troubleshooting, test each HDMI cable directly between the source and display.

Power Requirement — Critical

The BK-104 uses a DC 5V/2A power adapter.

Use the included power adapter or a compatible replacement with the correct voltage, polarity, connector, and current rating.

Understanding the Application Example

The application diagram shows one DVD or Blu-ray player connected to HDMI IN and multiple 8K TVs connected to HDMI OUT ports. The included power supply connects to DC 5V.

This demonstrates the main use case: one HDMI source shown on up to four HDMI displays at the same time.

Package Contents

The package includes:

HDMI cables are not listed as included.

Supported Video and Audio

The BK-104 supports video formats including:

Supported HDMI audio formats include:

Supported Technical Specifications

What Source Devices Is the BK-104 Compatible With?

The BK-104 is compatible with HDMI source devices such as:

1. 8K media players
2. 4K Blu-ray players
3. DVD players
4. Streaming devices
5. Cable boxes
6. Satellite receivers
7. HDMI 2.1 game consoles
8. Gaming PCs
9. Desktop PCs
10. Laptops with HDMI output
11. DVRs
12. NVRs
13. AV receiver outputs
14. HDMI switch outputs
15. HDMI matrix outputs 
     
    The source must output a supported HDMI format.

What Displays Is the BK-104 Compatible With?

The BK-104 can connect to HDMI displays such as:

1. 8K TVs
2. 4K@120Hz TVs
3. 4K TVs
4. 1080p TVs
5. Gaming monitors
6. Computer monitors
7. Projectors
8. Commercial displays
9. Digital signage displays
10. Classroom displays
11. Conference room displays
12. Home theater displays 
     
    Automatic scaling and HDR-to-SDR conversion help support mixed-resolution and mixed-HDR display setups.

Frequently Asked Questions

Q: What is the OREI BK-104 used for? 
A: It is used to split one HDMI source to up to four HDMI displays.

Q: Is the BK-104 a splitter or extender? 
A: It is an HDMI splitter. It does not extend HDMI over CAT cable by itself.

Q: How many HDMI inputs does it have? 
A: It has one HDMI input.

Q: How many HDMI outputs does it have? 
A: It has four HDMI outputs.

Q: Does it show the same content on all displays? 
A: Yes. All connected displays show the same HDMI source.

Q: Can it show different content on each display? 
A: No. It duplicates one HDMI input to all outputs.

Q: Can it extend my computer desktop across four screens? 
A: No. It mirrors the same PC screen to multiple displays.

Q: Does the BK-104 support 8K@60Hz? 
A: Yes. It supports up to 8K@60Hz 4:2:0 12-bit.

Q: Does it support 4K@120Hz? 
A: Yes. It supports up to 4K@120Hz 4:4:4 12-bit.

Q: Does it support HDMI 2.1? 
A: Yes. It is HDMI 2.1 compliant.

Q: What HDCP version does it support? 
A: It supports HDCP 2.3.

Q: What video bandwidth does it support? 
A: It supports 48Gbps FRL bandwidth and 18Gbps TMDS bandwidth.

Q: Does it support HDR? 
A: Yes. It supports HDR, HDR10, HDR10+, Dolby Vision, and HLG.

Q: Does it support VRR and ALLM? 
A: Yes. VRR and ALLM are listed as supported.

Q: Does it support QMS, QFT, and SBTM? 
A: Yes. These HDMI 2.1 features are listed as supported.

Q: Does it support downscaling? 
A: Yes. It supports 8K to 4K and 8K / 4K to 1080p automatic downscaling.

Q: Does it support HDR-to-SDR conversion? 
A: Yes. Automatic HDR-to-SDR conversion is supported on all outputs.

Q: Can I connect an 8K display and a 4K display at the same time? 
A: Yes. The manual states that you can connect 8K, 4K, and even 1080p displays at the same time with downscaling and HDR-to-SDR conversion.

Q: Will my 8K display keep 8K quality if a 4K display is connected? 
A: The manual states that mixed 8K and 4K or 1080p displays can be connected without compromising the quality of the 8K display, using downscaling and HDR-to-SDR conversion.

Q: What happens if the signal is converted to 1080p DVI? 
A: The manual notes that if the source is downscaled and converted to 1080p DVI based on display EDID, that output will not have sound.

Q: What is the factory-default EDID mode? 
A: DIP code 111, which copies HDMI OUT 1 sink EDID.

Q: Which EDID setting supports 4K60 4:4:4 with stereo audio? 
A: Use DIP code 110.

Q: Which EDID settings support 8K HDR? 
A: DIP codes 101, 100, 011, 010, 001, and 000 support 8K HDR modes with different FRL and audio selections.

Q: Does the BK-104 support Dolby Atmos? 
A: Yes. Dolby Atmos is listed as supported through HDMI audio pass-through.

Q: Does it support DTS:X? 
A: Yes. DTS:X is listed as supported.

Q: Does it extract audio to speakers? 
A: No. Dedicated audio extraction is not listed for this model.

Q: Does it have optical audio output? 
A: No. Optical audio output is not listed.

Q: Does it have analog audio output? 
A: No. Analog audio output is not listed.

Q: Does it support ARC or eARC? 
A: ARC and eARC are not listed.

Q: Does it support IR control? 
A: IR control is not listed.

Q: Does it support RS-232? 
A: RS-232 control is not listed.

Q: Can I use this splitter with an Elgato capture card to record games? 
A: No. The manual states that a capture card cannot be used with this device due to HDCP encryption on the outputs.

Q: What power adapter does it use? 
A: It uses a DC 5V/2A power adapter.

Q: What is the maximum power consumption? 
A: Maximum power consumption is 5.5W.

Q: What HDMI cable should I use for 8K@60Hz? 
A: Use an Ultra HDMI 2.1 cable between 2m and 3m / 6.6ft to 10ft.

Q: What HDMI cable should I use for 4K@60Hz? 
A: Use an HDMI 2.0 cable up to 8m / 26ft.

Q: What HDMI cable length is recommended generally? 
A: The manual recommends high-quality HDMI cables under 30ft.

Q: What should I do if there is no video output? 
A: Check if HDMI cables are connected properly, try changing the cables, and check whether the LEDs on the device are lighting up.

Q: What should I do if one display has no video? 
A: Check that display’s HDMI cable, selected input, power, and OUT LED. Also test the display on another HDMI output.

Q: What should I do if 8K@60Hz or 4K@120Hz does not work? 
A: Confirm the source, displays, EDID mode, and HDMI cables support the required format. Use Ultra High Speed HDMI 2.1 cables for 8K and 4K@120Hz.

Q: Does the BK-104 need external power? 
A: Yes. Connect the included DC 5V/2A multinational power supply.