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The RetroTink 5X is a great piece of kit – but it has been comprehensively overshadowed by its more recent stablemate, the RetroTink 4K.
You'd expect the creator of both of these devices, Mike Chi, to focus all of his time and energy on the 4K, especially as it's more powerful – but he's just released an update that brings a whole host of 'back ported' features from the 4K to the 5X, making the older, cheaper RetroTink even more appealing than it was previously.
"The 5X pipeline now uses the same 12bpc RGB 4:4:4 Linear Light pipeline as the 4K," explains Chi. "This allows it to output real Rec. 2020 HDR10 to produce CRT effects that are bright and color correct - much better than the old "injection" method."
The 5X's scanline engine now also supports energy normalisation thanks to update 4.00. "This was a feature introduced in the RT4K late last year to counter the black crush when variable width scanlines are used," says Chi. "This update also adds "Quasi-4K" output (for compatible displays) at 3840 and 2880 wide horizontal resolutions. Native horizontal 4K preserves the quality of RGB masks while letting the TV do the soft interpolation of scanlines in the vertical."
Chi explains that launch units of the 5X (Rev. A) may not be stable above 1080p "until the Gen Lock code is reworked." Units sold before the middle of 2022 (Rev. B) have "degraded shadow mask quality." However, if you bought your 5X after mid-2022 (Rev. C), you're in luck, as those have full RGB 4:4:4 shadow mask support and therefore suffer from no limitations.
"This firmware branch is hyper-focused on CRT simulation," explains Chi. "For 480i heavy users, the older 3.XX firmware with edge-interpolated MADI may be better unless you prefer CRT simulation scanlines." He adds that this should be considered a "branch" firmware and not a complete replacement. "We noticed that many people want a more "plug and play" experience to just replace their CRT. Version 4.0 aims to do this and bring the 5X output closer in line to the latest capabilities of modern TVs."
Here's the full rundown of this update:
+ Version 4.0 “CRT Simulation Edition”
+ Ported RT4K RGB 4:4:4 12bpc Linear Light pipeline
+ Outputs true HDR10/HLG with Rec. 2020 conversion and adjustable PQ
+ Scanline engine supports Energy Normalization
+ RGB Shadowmask and new CRT presets
+ “Quasi-4K” modes with 3880×960, 2880×1200, 2880×1080 output for full native horizontal resolution on 4K TVs to preserve mask quality
+ Limitations –Rev A (Launch PCBs) may be capped to 1080p until the Gen Lock code is rewritten –Rev B (before mid-2022) have degraded shadow mask quality, the mask may need to be changed to a mono type –Rev C, the majority of units made, have no limits –Current build does not have inverse telecine or MADI, which requires further and extensive re-optimization and memory management. -This branch is focused on maximizing the quality of CRT effects and plug and play operation (generic sampling, CRT-sim deinterlace, etc.)
The reaction to this update has been very positive, as you can imagine. "Holy shit - this is AMAZING," says Voultar, creator of the SNES Edge Enhancer. "RT5X running in 4K (horizontal) with real HDR10 and the same shaders that the Tink4K shines with. Mike's a wizard for pushing and overclocking this old puppy. I've never seen a legacy product have cutting-edge features like this!"
You can grab the update here.