AJA KONA 4 review

AJA's KONA 4 is a professional PCIe video I/O card for a production computer that already speaks SDI. Its 4K headline is real, but it describes a four-link 3G-SDI setup—not the single-cable 12G route of the newer KONA 5. The card can be assessed for 4K60 capture in either AJA Control Room or OBS when its 4K firmware, four SDI inputs, transport setting and host are all right. It is not a plug-in HDMI console card, and its output ports do not by themselves establish gaming-style passthrough. This is a documentation-based assessment, not a hands-on review.

Identify the card and the direction of each connection

KONA 4 is an eight-lane PCIe 2.0 board with four DIN 1.0/2.3 sliding-sleeve SDI connections. Each can be assigned to input or output, and AJA lists SD/HD, dual-link HD and 3G HD-SDI input modes. The small connector type is easy to overlook: a standard BNC cable does not plug straight into the card. AJA's manual shows a model-specific DIN-to-full-size-BNC adapter snake and other breakout leads, but a used or reseller package still needs an exact contents check.

The mini-HDMI socket is a monitoring output, not an HDMI input. AJA's current product page contains one general connectivity sentence that calls the output HDMI 2.0b, but its technical sheet, card diagram, v18 manual and KONA 4-versus-5 FAQ repeatedly specify HDMI 1.4b. I use that narrower, repeated model-specific specification. If your source is an HDMI-only console or camera, the KONA 4 is the wrong direct-input choice; converting HDMI to SDI would require a separately verified signal chain.

4K60 is four 3G-SDI links, with one firmware personality at a time

AJA lists 4K DCI and UltraHD formats up to 60p. Its model-specific comparison says the KONA 4 takes four 3G-SDI cables to ingest or output 4K/UltraHD 60p. Connect all four lanes to the matching source and choose the SDI 4K transport; do not mistake four ports for four independent 4K60 feeds. The exact transport, raster and cabling still need to match the signal sent by the production source.

The manual describes two firmware personalities. Its 4K firmware supports 4K/UltraHD along with HD and SD, while the separate UFC firmware supports SD, HD and 2K and provides up/down/cross-conversion—but not 4K. Those modes are mutually exclusive, not a menu of features that can be combined on one installation. AJA's OBS v17.1 guide also lists the KONA 4 for four-link 4K input and instructs users to choose a 4K format and SDI transport. The guide describes up to two UHD channels on the four input links and warns that multi-channel 4K takes a powerful host. This assessment only assigns a one-source 4K60 plan; it does not promise two simultaneous 4K60 recordings.

OBS and Control Room are both supported, but check the exact job

AJA names OBS Studio and Control Room for the KONA family, and its OBS guide lists KONA 4 under Windows and Intel/Apple-silicon Mac PCIe devices. That guide separates firmware modes, gives KONA 4 a 4K input workflow, and distinguishes capture configuration from output routing. The reviewed 4K60 plans therefore include a single SDI source in OBS or Control Room, with the 4K firmware and four inputs; an application label alone is not proof that every raster, frame rate, output route and number of streams is supported by every version.

HDR is a more conditional case. AJA says Control Room can capture HDR metadata from incoming SDI or HDMI into a .mov file, and the sheet includes HDR signaling, but AJA also says HDR support depends on the application. The fact record assigns only a Windows 1080p60 SDI/Control Room metadata-preservation plan, whose source format is otherwise listed. It does not extend that evidence to OBS HDR or a 4K60 HDR recording recipe. Confirm the source's HDR transfer characteristics, raster, firmware and current application version before using that requirement.

PCIe, power, cables and the different KONA 5 route

KONA 4 uses PCIe 2.0 x8 and AJA's FAQ says it draws power from the PCIe bus. That differs from KONA 5, which uses PCIe Gen 3 and requires a separate ATX connection. It also differs in the signal path: KONA 4's 4K60 capture uses four 3G links, while KONA 5 offers a single-link 12G-SDI route. KONA 4 has DIN 1.0/2.3 connectors and a mini-HDMI 1.4b monitor output; KONA 5 uses HD-BNC SDI and a full-size HDMI 2.0 monitoring output. A product family name is not enough when comparing used cards or card/chassis bundles.

The current reference page and versioned software documents establish Windows and Mac routes, but the actual driver branch still depends on the operating-system release and, for Mac, the processor generation. Before purchase, check that the workstation has a suitable eight-lane PCIe path, room for the card, four correct SDI input cables, enough storage/host capacity for the chosen raster, and the exact AJA firmware and Control Room or OBS version. If the offer is an Io Xpand package, it is a different configuration from the standalone board reviewed here.

Who should put it on a shortlist

KONA 4 makes sense for an established SDI edit, mastering or live-production system that needs a documented four-link 4K input path, model-specific HD/2K conversion, or the assessed Windows 1080p60 HDR-metadata arrangement. It is a poor fit for a consumer HDMI source, an external USB setup, a Thunderbolt-only laptop without a separately verified PCIe chassis, or a buyer expecting the simple one-cable 12G 4K path of a KONA 5. The appropriate purchase check is the exact KONA 4 card plus correct cables, not the similar-looking IO-XPAND-03/KONA 4 bundle, another KONA model, or a generic listing that omits the connector and firmware details.

Primary references: AJA's KONA 4 product page and current specification sheet; its KONA Series Manual v18, OBS Quick Start Guide v17.1 and KONA 4 versus KONA 5 FAQ; and AJA's KONA compatibility chart.