The Ultimate 4K Toolbox, FS4 is a 4-Channel 2K/HD/SD or 1-Channel 4K/UltraHD frame synchroniser and up, down, cross-converter.

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SKU: AJA-FS4 Categories: , Tag:


The Ultimate 4K Toolbox, FS4 is a 4-Channel 2K/HD/SD or 1-Channel 4K/UltraHD frame synchroniser and up, down, cross-converter.

FS4 REAR Connections

AJA’s flagship frame synchroniser and converter offers incredible versatility and connectivity in a sleek 1RU frame for all your 4K/UltraHD and 2K/HD/SD conversion needs, with a wealth of digital and optional 12G-SDI Fibre LC and 12G-SDI BNC SFP connectivity. Offering a wide range of connection options for both video and audio, FS4 can do the work of four separate devices in 2K/HD/SD or combine all processors and channels together for maximum flexibility for 4K/UltraHD productivity.

AJA FS4 Firmware Version 2.0 Update

  • 1080i Output Filter control for vertical prefiltering of progressive images prior to interlacing.
  • SDI Ancillary packet pass-through whenever the input and output formats and frame rates match.
  • Audio Delay now displayed in milliseconds and audio samples.
  • Processor channel names can now be edited for easier identification.
  • Along with some fixes and Improvements.
  • Maintain A/V Sync couples video and audio delay controls to maintain audio-sync when adjusting Video Timing.

Release NotesUpdate

Single or Four Channel Modes in a 1RU frame

FS4 offers two modes for comprehensive conversion and signal processing :

Single Channel mode provides a full suite of 4K/UltraHD processing and up, down, cross-conversion to and from 2K, HD or SD.

Four Channel mode offers 4 x 2K/HD/SD channels of simultaneous conversion and processing, all within an elegant 1RU chassis for multi-channel high density delivery.

Single Channel Mode

AJA FS4 Single Channel Architecture

Bulletproof reliability. Incredible conversion power (View Architecture)

4K/UltraHD delivery, processing and synchronisation is fast becoming the next standard, and FS4 gets you there with a wealth of digital video connectivity including Quad 1.5G, Dual 3G, Quad 3G over 3G-SDI and 12Gb/6Gb over optional 12G-SDI BNC and 12G-SDI LC Fibre SFP modules.

In single channel mode, FS4 will up scale your HD or SD materials to 4K/UltraHD and back, with a huge array of audio channels over Fibre, 3G-SDI, AES, and MADI for an incredible 272 x 208 matrix of audio possibilities.

Four Channel Mode

AJA FS4 Four Channel Architecture

In four channel mode FS4 provides incredibly powerful multi-channel conversion with up to 4 channels of simultaneous processing for 2K/HD and SD signals. Powerful processing allows Region of Interest (ROI) scaling, colour correction, proc amp controls, motion adaptive de-interlacing and much more.

Multi-channel density in a 1RU Chassis. Space, energy and power possibilities preserved. (View Architecture)

New Thinking, New Interface

New thinking requires a new layout and FS4’s front panel has been redesigned to simplify and speed your access to the product’s wealth of features. The panel has also been designed to provide straightforward operation in single channel or four channel mode. In four channel mode, all four VIDx buttons under Channel Select are lit up. In single channel mode, only VID1 is lit and VID2-4 are off.

Up, Down, Cross-Conversion

Moving to 4K is never an instant change. Legacy signals and archival material need to be integrated into the 4K environment while 4K sources need to be down-converted for current 2K/HD pipelines.

Utilising AJA’s remarkable conversion algorithms, FS4 supports up, down, cross-conversion from SD, HD or 2K over 12G/6G/3G-SDI video to 4K or UltraHD video and back. Both Quadrant (Square Division) and 2SI (Two Sample Interleave) output formats are supported.

AJA’s powerful hardware conversion technology ensures the highest image quality for your productions. Key conversion features include:

  • 4K/UltraHD/2K/HD/SD up, down-conversion
  • SD/SD aspect ratio conversion
  • HD/HD cross-conversion (720p/1080i)

All done in beautiful 10-bit with dedicated hardware.

Incredible Digital Connectivity

Video and Audio deserve the connectivity and bandwidth required to meet the demands of your projects.

FS4 utilises standard BNC as well as optional SFP inputs and outputs to integrate easily into a variety of workflows and facilities with support for SDI worklows all the way up to 12G.

FS4 has BNC and Fibre* inputs and outputs to accept 4K/UltraHD/2K/HD/SD resolution SDI signals in Single Channel Mode. In Four Channel mode 2K/HD/SD inputs can be be routed to multiple locations simultaneously without the need for any external signal distribution.

A looping Reference Input allows the FS4 to be locked to your house reference signal for rock solid stability.

Digital Audio can be dis-embedded and embedded between SDI, MADI and AES for an incredible array of routing possibilities.

AJA FS4 Back Large

12G/6G HD-BNC and Fiber SFP Options

FS4’s SFP options include both 12G/6G-SDI HD-BNC and Fibre I/O options, allowing great SDI flexibility and fibre cable runs of up to 10 kilometres to be connected directly to the FS4 without the need for separate fibre to SDI conversion.

Massive Audio Flexibility

The growth of 5.1 and 7.1 audio has increased the number of audio channels that must be managed in a production, The MADI standard provides a convenient way to transport huge numbers of audio channels along a single cable, simplifying the cabling demands for broadcasters, mobile trucks and production. FS4 supports both fibre and coax MADI input and output. An internal 277 x 208 mono audio matrix allows you to route 1 to 1 or 1 to many with full routing of MADI, mix-downs and all audio coming from SDI, fibre and AES sources for an incredible amount of audio processing capability in a single box.

Closed Caption Conversion

FS4 supports closed captioning and the conversion of closed captioning between 2K/HD/SD and 4K/UltraHD formats – including full conversion of CEA-608 and CEA-708 standards. FS4 can preserve closed captioning even when converting between formats, removing the need to reinsert closed captions after conversion.

Active Format Description

Automatically sets Active Format Description information to match the converted signal. This means AFD information does not have to be inserted after conversion and provides accurate information for devices that understand AFD.

Remote Configuration and Control

FS4 is network ready and supports SNMP monitoring and web-based remote control. Units can be connected to any Ethernet network via the built-in 10/100/1000MB Ethernet port, allowing control and configuration of multiple FS units from any web browser on a connected computer. Configurations can be saved and applied to multiple units, ensuring consistency and quick configuration in large installs.

To integrate smoothly with the existing automation of a facility, FS4 can also receive external GPI commands to trigger a variety of functions.

FS Family Brochure

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