Key Digital KD-DA1x4DC User manual

4K/18G 1x4 HDMI Distribution Amplifier /
4K to 1080p Down-converter with
L/R and Optical Audio De-Embedding
Operating Instructions
KD-DA1x4DC

2
Table of Contents
Introduction .................................................................... 1
Quick Setup Guide ............................................................... 2
Application Example .............................................................. 2
Front & Rear Panel Connections, Buttons, and LEDs ....................................... 3
Specifications ................................................................... 7
Important Product Warnings & Safety Instructions ......................................... 8
Contacting Key Digital ............................................................. 9
Warranty Information.............................................................. 9
© 2023 Key Digital, Inc. All rights reserved.
Visit the product page for most recent
version of the manual, quick setup
guide, firmware, control drivers and
all additional downloads.
Always follow the instructions provided in this Operating Manual.
Please visit www.keydigital.com for the latest product documentation and software
downloads. Product features and specifications are subject to change without notice.

1
Introduction
Key Digital®KD-DA1x4DC is a 4K 18G HDMI Distribution Amplifier with 4K to 1080p resolution
down conversion option to enable a single HDMI video source to be displayed on multiple video
displays, regardless of 4K or 1080p resolution support. KD-DA1x4DC is engineered to offer the
best quality, performance, and reliability at a cost-effective price point and has been designed for
professional audio video installations in digital signage, surveillance monitoring applications, and
more. KD-DA1x4DC features L/R analog and optical digital audio de-embed ports, enabling ease
of integration into amplifiers, distributed audio systems, or sound bars. KD-DA1x4DC supports
all video resolutions up to 4K/UHD, 4:4:4 chroma sub-sampling, 12bit deep color, and HDR.
EDID handshaking and Forced Hot Plug Detection professional tools help overcome common
HDMI handshaking and integration problems for ease of installation in any environment.
Key Features
›HDMI Signal Distribution: 1 HDMI source to 4 HDMI outputs/displays
›Ultra HD/4K Support: 4096x2160 or 3840x2160 24/25/30/60hz at 4:4:4
(signals up to 18Gbps bandwidth)
›HDCP Licensing: Fully licensed and compatible with HDCP 2.2
›HDR10 and Dolby Vision®: More life-like images through a greater range of luminance levels
›Resolution Support: Supports all SD, HD, and VESA (VGA, SVGA, XGA, WXGA, SXGA, UXGA)
up to 4096x2160p.
›4K to 1080p Down Convert: When enabled, resolution conversion is applied to individual output(s)
based on EDID from the connected display
›Deep Color Support: Up to UHD/4K 30Hz 4:4:4/12 bits or 60Hz 4:4:4/8 bit
›Audio De-embedding: Audio of the connected HDMI input is output at the digital Optical and analog
3.5mm stereo connectors.
›Full Buffer System™:Manages TMDS re-clocking / signal re-generation, HDCP authentication to
source & display, and EDID Control handshake
›EDID Management: Internal library with 15 internal EDID handshakes including 4K with HDR in
addition to native EDID data copied from output/display 1
›Digital Audio Format Support: DTS-HD Master Audio™, DTS:X®, Dolby®TrueHD, Dolby Atmos®
›CEC Disconnect: Prevents unwanted control of source
Included Accessories
›Power Supply: KD-PS5V1ASC 5V/1A DC power jack, screw-in type
›Mounting Brackets: 2 L-shaped

2
Quick Setup Guide
CONNECT:
Test for proper operation of the unit and cables in your system before permanently
securing the unit for final installation. Ensure that you leave enough ventilation
space to provide sufficient airflow and cooling.
1. Begin with the KD-DA1x4DC unit and all input/output devices turned off with power and HDMI
cables removed
2. Connect your HDMI source to the input port of KD-DA1x4DC unit
3. Connect your HDMI displays to the output ports of KD-DA1x4DC unit
4. Connect the analog and/or digital audio amplifiers/receivers via the analog 3.5mm and optical outputs
5. BEFORE connecting power supply to power outlet, screw-in the power supply to the KD-DA1x4DC
unit
6. AFTER ALL CONNECTIONS ARE MADE, plug-in power supply to power outlet
7. Power on input and output devices
CONFIGURE:
›The default position of the Down-Convert switch is OFF. If sending 4K content to 4K and 1080p
displays, set to the AUTO position.
Application Example
4K Video Source Down-Convert Applied
KD-DA1x4DC
HDMI
HDMI
Optical Audio
HDMI

3
Rack Mounting:
In addition to mounting with the supplied L-Brackets, multiple KD-DA1x4DC may be mounted in
KD-SMS16 using the side mounting screws. KD-SMS16 is a mounting shelf for Key Digital units with
side mounting screw spacing of 2.912”, 2.582”, or 2.252”
Do NOT exceed 12 units as doing so will result in unit damage by overheating.
Front & Rear Panel Connections, Buttons, and LEDs
REAR PANEL
HDMI Inputs
›The HDMI input is located on the left side of the back panel.
›Blue LED illuminates solid to indicate an active HDMI signal is incoming.
HDMI Outputs
›4 HDMI outputs are located on the center to right side of the back panel.
›Blue LED illuminates solid when Hot Plug Detection (HPD) is received from the connected display/
output device

4
HDMI Input/Output Port Specifications
›Supports up to UHD/4K @ 50/60 fps [4:4:4], 18Gbps signals
›Supports HDR10. Compliant with HDCP 2.2 and previous.
›Supports lossless compressed audio formats including Dolby®TrueHD, Dolby®Digital Plus,
Dolby Atmos®, and DTS-HD Master Audio™
›CEC Channel is not connected within unit, which prevents the source from receiving CEC commands
from displays. This is non-adjustable.
›For Display Port sources/monitors, use active converters
Supported standard 4K Video Formats:
Resolution Bandwidth
1 4K@24/25/30 [4:4:4] 8bit < 10.2Gbps
2 4K@24/25/30 [4:2:2] 8/10/12bit < 10.2Gbps
3 4K@50/60 [4:2:0] 8bit < 10.2Gbps
4 4K@24/25/30 [4:4:4] 10/12bit < 18Gbps
5 4K@50/60 [4:2:2] 8/10/12bit < 18Gbps
6 4K@50/60 [4:2:0] 10/12bit < 18Gbps
7 4K@50/60 [4:4:4] 8bit < 18Gbps
Analog L/R Audio Output
›3.5mm stereo jack with de-embedded audio from the selected HDMI source
›Automatically mutes if audio formatting is not PCM 2ch
Optical Audio Output
›Optical audio output with de-embedded audio from the selected HDMI source
›SPDIF IEC 60958 format
›Supports multi-channel Dolby®and DTS™surround formats up to 5.1
›Automatically mutes if audio formatting is not PCM, Dolby®, or DTS™

5
Audio Ports Specifications
›Each audio output drives audio signals up to 2VRMS with a sampling rate of 192KHz
›There are no volume or tone control features
›There are no DSP features
Audio Input Signal Format Audio L/R Output Digital Audio Output (Optical)
2ch PCM Pass-Through Pass-Though
Multi-Channel PCM Front L/R Pass-Through MUTE
Dolby DTS MUTE Pass-Though
HD Audio MUTE MUTE
FRONT PANEL
Input Active LED
»1 blue LED illuminates solid to indicate an active incoming HDMI signal
»LED blinks steadily if there is no active incoming signal.
Output Active LED
»2 blue LEDs illuminate solid when Hot Plug Detection (HPD) is received from the connected display/
output device and there is an active incoming HDMI signal from video source.
Service (Factory) USB
»This port is for factory servicing only. Does not have standard USB functionality.

6
Forced HPD Troubleshooting Tool
»When ON, Hot Plug Detection voltage is fixed on to the connected display
»Standard HPD behavior when set to OFF position
EDID Handshaking Rotary
»EDID authentication is provided from the unit to the connected inputs/sources.
»The EDID file (AKA “handshake”) is selected using the EDID rotary on the unit and provides a list
of compatible video and audio formats as well as digital data, informing the source device what it
should output.
»Most sources will comply with a new EDID file without a power-cycle, but devices do behave
differently
»Adjustments may speed up sync time during source selection.
Position EDID Handshake Description EDID Rotary
0Copy EDID from HDMI Output 1
Note: Default position
is “A”
11080i, 2CH AUDIO
21080i, DOLBY/DTS 5.1
31080i, HD AUDIO
41080p, 2CH AUDIO
51080p, DOLBY/DTS 5.1
61080p, HD AUDIO
74Kx2K@60, 10.2G, HDR, 2CH AUDIO
84Kx2K@60, 10.2G, HDR, DOLBY/DTS 5.1
94Kx2K@60, 10.2G, HDR, HD AUDIO
A4Kx2K@60, 18G, HDR, 2CH AUDIO
B4Kx2K@60, 18G, HDR, DOLBY/DTS 5.1

7
C4Kx2K@60, 18G, HDR, HD AUDIO IMPORTANT: Please
apply light pressure
to the EDID rotary
when making your
selection.
D1280x720p@60 DVI (no audio)
E1920x1080p@60 DVI (no audio)
F4Kx2K@30, 10.2G, HDR, 2CH AUDIO
»Note: For Dolby Vision®, you must connect the Dolby Vision®supported display/device to
Output 1, and the EDID rotary must be set to 0. Dolby Vision®signals may not be down-converted.
Black image / no image will result.
4K to 1080p Down Convert Tool
»When set to AUTO, KD-DA1x4DC will down convert incoming 4K content to 1080p for an individual
output only if the EDID file from that individual display informs KD-DA1x4DC that the connected
displays supports 1080p (not 4K).
»Down Convert works individually. KD-DA1x4DC can apply resolution down conversion to any output
without affecting the other output.
Specifications
Technical:
»Input: HDMI Connector, Type A, 19 Pin Female
»Output (Each): HDMI Connector, Type A, 19 Pin Female
»Bandwidth: TMDS bandwidth 18 Gbps
»DDC Signal (Data): Input DDC Signal - 5 Volts p-p (TTL)
»HDMI Video/Audio Signal: Input Video Signal - 1.2 Volts p-p
»Power Supply: KD-PS5V1ASC 5V/1A, 100-240VAC, 50-60Hz,
Interchangeable head, screw-in connector
General:
»Regulation: CE, RoHS, WEEE
»Enclosure: Black Metal
»Product Dimensions: 7.4” x 2.72” x 0.78” (188 x 69.2 x 19.9mm)
»Packaging Dimensions: 9.44” x 5.67” x 3.15” (240 x 144 x 80mm)
»Product Weight: 0.7 lb
»Shipping Weight: 1.4 lb

8
Important Product Warnings:
1. Connect all cables before providing power to the unit.
2. Test for proper operation before securing unit behind walls or in hard to access spaces.
3. If installing the unit into wall or mounting bracket into sheet-rock, provide proper screw support
with bolts or sheet-rock anchors.
Safety Instructions:
Please be sure to follow these instructions for safe operation of your unit.
1. Read and follow all instructions.
2. Heed all warnings.
3. Do not use this device near water.
4. Clean only with dry cloth.
5. Install in accordance with the manufacturer’s instructions.
6. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus
(including amplifiers) that produce heat.
7. Only use attachments/accessories specified by the manufacturer.
8. Refer all servicing to qualified service personnel. Servicing is required when the device has been
damaged in any way including:
»Damage to the power supply or power plug
»Exposure to rain or moisture
Power Supply Use:
You MUST use the Power Supply PROVIDED with your unit or you VOID the Key Digital®Warranty
and risk damage to your unit and associated equipment.

9
Contacting Key Digital
®
Technical Support
For technical questions about using Key Digital®products, please contact us at:
›Phone: [phone]
›E-mail: [email protected]
Repairs and Warranty Service
Should your product require warranty service or repair, please obtain a
Key Digital®Return Material Authorization (RMA) number by contacting us at:
›Phone: [phone]
›E-mail: [email protected]
Warranty Information
All Key Digital®products are built to high manufacturing standards and should provide years of
trouble-free operation.
They are backed by a Key Digital Limited 3 Year Product Warranty Policy: https://keydigital.org/warranty

Key Digital®, led by digital video pioneer Mike Tsinberg,
develops and manufactures high quality, cutting-edge
technology solutions for virtually all applications where
high-end video and control are important. Key Digital®
is at the forefront of the video industry for Home
Theater Retailers, Custom Installers, System Integrators,
Broadcasters, Manufacturers, and Consumers.
Rev 1 – Feb 2023
Key Digital®:: 521 East 3rd Street :: Mount Vernon, NY 10553
Phone : [phone] Fax : [phone] Web : www.keydigital.com