4x4 8K 48Gbps HDMI 2.1 Matrix Switcher with Audio De-Embedding

What is audio de-embedding and why does the VLMX-8K4x4AIR need it?
Audio de-embedding extracts the audio signal from an HDMI stream and outputs it separately, so it can be sent to an AV receiver, DSP, or amplifier instead of relying on the display's built-in speakers. The VLMX-8K4x4AIR de-embeds audio on all four outputs simultaneously, providing four optical S/PDIF outputs (LPCM 2.0CH, Dolby/DTS 5.1CH) and four balanced analog outputs on Phoenix connectors (LPCM 2CH). This eliminates the need for four separate external de-embedders in the rack and keeps HDMI video routing and audio distribution in a single 1U device.

Can the audio be routed independently of the video?
Yes. The VLMX-8K4x4AIR offers three audio de-embed modes. "Bind to Input" locks each audio output to a specific HDMI input. "Bind to Output" makes audio follow whatever source is routed to that HDMI output. "Audio Matrix" mode decouples audio entirely, allowing any of the four inputs — or ARC return audio from any of the four displays — to be routed to any of the four audio outputs independently of the video routing.

Does the VLMX-8K4x4AIR support 8K@60Hz on all four outputs at once?
Yes. The matrix maintains full 48Gbps HDMI 2.1 bandwidth on every input and output simultaneously, with no bandwidth sharing as port utilization increases. All four outputs can carry 8K@60Hz 4:2:0, 8K@30Hz 4:4:4, or 4K@120Hz 4:4:4 at the same time. For 8K signal integrity, use Ultra High Speed HDMI 2.1 cables of 3m or less on both the input and output side.

How does per-output downscaling work?
Each of the four HDMI outputs has its own independent scaling setting, configurable from the front panel LCD, RS-232, or Web GUI. Available modes are Bypass (native pass-through), 8K to 4K, 8K/4K to 1080p, Auto (matches the connected display's EDID), and Audio Only. This means a single 8K source can be routed to an 8K display at native resolution while simultaneously feeding a 1080p display that receives a downscaled version — with no external scaler required at either display.

Does it support VRR and ALLM for gaming consoles?
Yes. The VLMX-8K4x4AIR passes the complete HDMI 2.1 gaming feature set: VRR (Variable Refresh Rate), ALLM (Auto Low Latency Mode), QMS (Quick Media Switching), QFT (Quick Frame Transport), and SBTM (Source-Based Tone Mapping). Combined with zero-latency switching and 4K@120Hz 4:4:4 support, this makes the matrix suitable for routing next-generation consoles and high-refresh gaming PCs without introducing input lag or tearing.

What is ARC on this matrix and how is it used?
ARC (Audio Return Channel) allows a connected display to send its own audio back to the matrix over the same HDMI cable — for example, audio from a smart TV app or an over-the-air tuner. ARC can be enabled or disabled per output on the VLMX-8K4x4AIR. When enabled, that display's return audio becomes available as a selectable source inside the 4x4 audio matrix, so it can be routed to any optical or balanced analog audio output and into a house audio system.

How do I control the VLMX-8K4x4AIR?
Four control methods are supported. Front panel buttons with an LCD display allow direct output-then-input switching and full menu navigation. An included IR remote provides source selection per output, with an IR EXT port for installations where the front panel is out of line of sight. RS-232 (D-Sub 9, 4800–115200 baud) supports third-party control systems including VigilLynx™, Crestron, AMX, and Extron. A built-in Web GUI over TCP/IP (default IP 192.168.0.100, DHCP selectable) provides full remote configuration from any browser on the network.

What EDID options are available?
The VLMX-8K4x4AIR includes 43 EDID modes: 36 factory-defined presets, 3 user-defined EDID slots, and 4 copy-from-output modes. Factory presets cover resolutions from 1080p through FRL12G 8K HDR, each with 2.0CH, 5.1CH, or 7.1CH audio variants. Copy modes read the EDID directly from a connected display and apply it to a chosen input, which is the fastest way to resolve handshake issues with a specific source-display combination. EDID is set per input from the front panel, RS-232, or Web GUI.

Does the matrix remember its routing after a power outage?
Yes. Power-cut memory retains the last routing configuration and restores it automatically when power returns, except when the unit was placed into standby mode before the power loss. Factory reset is available from the front panel, Web GUI, or RS-232 command.

What is the difference between the VLMX-8K4x4AIR and the VLMX-8K8x8AIR?
The two models share the same HDMI 2.1 feature set — 48Gbps bandwidth, 8K@60Hz support, HDCP 2.3, per-output downscaling and HDR conversion, VRR/ALLM/QMS/QFT/SBTM, and identical audio de-embedding architecture. The difference is port count and power. The VLMX-8K4x4AIR provides 4 inputs, 4 outputs, 4 optical and 4 balanced analog audio outputs, and ships with a 24V/2.7A power supply. The VLMX-8K8x8AIR doubles this to 8 inputs, 8 outputs, and 8 of each audio output type, with a 24V/3.75A supply. Choose the 4x4 for home theater, boardrooms, and compact control rooms; choose the 8x8 when source or display count exceeds four, or when system growth is anticipated.