AJA Io Xpand / KONA 4 bundle (IO-XPAND-03) review

The IO-XPAND-03 is AJA's Thunderbolt Io Xpand enclosure sold with a KONA 4 PCIe I/O card and its card cables. That package identity matters: IO-XPAND-01 is the separate chassis-only configuration, while IO-XPAND-02 and IO-XPAND-04 include different KONA cards. This assessment is about the exact KONA 4 bundle, not a KONA 4 card already installed in a desktop or an unspecified used Io Xpand. It is aimed at a post-production or broadcast setup that already works with SDI, not a plug-in HDMI gaming device.

What KONA 4 brings—and what its ports do not mean

The KONA 4 card is an 8-lane PCIe 2.0 professional video and audio I/O board with four bidirectional SDI connectors and a mini-HDMI 1.4b output. The SDI connectors are the DIN 1.0/2.3 type, not four ordinary full-size BNC sockets; plan for the correct cables or adapters and check what is actually in a seller's box. AJA's format sheet lists 4K and Ultra HD through 60p, alongside HD through 60p. It also lists 4K HDR signaling and HDMI output formats, but those output or metadata details are not evidence of a rate-specific HDR capture file in a selected application. This review does not assign HDR capture or consumer display passthrough.

For the assessment's higher-rate plan, the computer connection is Thunderbolt 5 and the software is AJA Control Room. That does not turn the old card's PCIe 2.0 interface into a native 12G-SDI card: AJA's KONA 4 specification lists SDI input formats up to 3G, and its manual treats 4K as a transport mode with connector configuration that must match the signal. Check AJA's exact KONA Control Panel setup, the source's raster/frame rate, the required multi-link cabling, and whether the application can use the selected mode. The record deliberately keeps a separate 1080p60 path for Thunderbolt 3/4 arrangements rather than carrying the 4K maximum to every host link.

Control Room is not an OBS 4K promise

AJA's versioned OBS Quick Start Guide includes KONA 4 among the supported devices and shows Windows and Mac software paths. This assessment assigns OBS only a single-source 1080p60 setup. KONA 4's 4K/Ultra HD 60p line in its product sheet is a hardware-format ceiling, not proof that an arbitrary OBS release, plugin, firmware, host and multichannel wiring combination records that target. The higher mode is matched only with AJA Control Room on the Thunderbolt 5 configuration, and still requires the right KONA firmware and signal route.

The Io Xpand manual lists Windows 11 with Thunderbolt 5/4 or USB4, and Mac M-series or Intel Macs with Thunderbolt 3 and macOS 15 or later. It separately states that a KONA card needs AJA Desktop Software even though the chassis itself needs no additional driver. Current AJA Desktop Software v18 on Mac is Apple-silicon-only; an Intel Mac requires the supported v17.6 branch. The generic finder only says Thunderbolt and Mac, so its result cannot establish port generation, processor family or driver version. Before relying on a match, confirm those specifics against the actual computer.

How it compares with the adjacent bundles

KONA 4 sits between KONA 5 and KONA 1 in this three-package group. It is a multi-channel broadcast card with an SDI-based 4K mode, while KONA 5 moves to 12G-SDI and has the more explicit single-link 4K60 input-and-monitor configuration. KONA 1 is the simpler single-channel 3G-SDI board for HD/2K/SD work. The KONA 4 HDMI connector is for output; if an unencrypted HDMI source must enter the computer, these bundles are the wrong input family. A compact consumer HDMI capture unit may be easier for that job, though it does not replace the specific broadcast routing functions of the KONA card.

Before ordering, check the IO-XPAND-03 code, the included KONA 4 card and cable kit, the chassis power supply and Thunderbolt cable, physical space for the expansion box, the host's real Thunderbolt support, the SDI adapter/cabling required for your source, and the exact driver/application release. The manufacturer's page establishes the package variant but not a retailer's individual contents, stock, warranty or current price. This is a documentation-based assessment, not a hands-on test.

Primary references: AJA's Io Xpand page and manual v1.0; the KONA 4 product page and specification sheet; AJA's KONA Series Manual v18 and OBS Quick Start Guide v17.1.