When Chaining a RetroTINK or OSSC Scaler with an mClassic Helps and When It Hurts

Place the Marseille Inc. MCL-001 dongle after your RetroTINK or OSSC and before your display. The result is rarely a free improvement. The mClassic adds a post-process edge smoothing filter and a 1080p to 1440p upscale. That cleans up jagged edges on 3D games. It softens pixel art and interferes with scanline filters. The trick is knowing which output resolution to send from the scaler and which LED mode to set on the mClassic. Send 1080p from the scaler into the mClassic for the dongle to process. Send 1440p from the scaler and the mClassic enters passthrough, doing nothing. Send 480p and the mClassic upscales it, but the result has a smaller active image area and more softening than feeding it 1080p. The chain order is fixed: scaler first, mClassic last. Reversing them breaks the processing entirely.

Feeding the OSSC 1080p Into the Dongle

An mClassic after OSSC setup requires the OSSC to output exactly 1080p. The OSSC is a line multiplier with no framebuffer, so its output is a direct multiple of the input resolution. For a 240p source such as an SNES at 256x224, you set the OSSC to Line5x mode. That produces 1280x1120, which is not a standard HDMI resolution. You then enable the OSSC's 1080p output mode, which adds padding to reach 1920x1080. The mClassic receives this 1080p signal and, with its blue LED mode engaged, applies context-adaptive edge smoothing and upscales the active image area to 1440p. The claimed 1440p output from Marseille is technically correct, but independent testing by RetroRGB and My Life in Gaming confirms the active image area is 1080p upscaled, not a native 1440p render. The dongle is not generating new pixel data at 1440p; it is stretching and softening the 1080p frame.

Avoid Sending 480p From the OSSC

The failure case here is feeding the mClassic 480p from the OSSC. The OSSC can output 480p from a 240p source via Line2x mode. If you then pass that to the mClassic, the dongle upscales it to 1440p, but the active image area is only 480p worth of information stretched four times. The result is visibly softer, with more ringing halo artifacts around edges. The correct intermediate resolution is always 1080p. Set the OSSC to output 1080p, and only then connect the mClassic.

Set the RetroTINK 5X to 1080p Output

A RetroTINK 5X mClassic chain works best when the RetroTINK 5X outputs 1080p and the mClassic upscales to 1440p. The RetroTINK 5X is a framebuffer scaler, not a line multiplier, so it can output 1080p directly from any input resolution. This makes the chain simpler than with the OSSC. Set the RetroTINK 5X to 1080p output, enable the mClassic's blue LED mode, and the dongle applies its edge smoothing and upscale.

Skip the Chain for 2D Pixel Art

Skip this chain entirely when you are playing 2D pixel art games. The mClassic's context-adaptive processing treats every edge as a jaggie to smooth. On a pixel art sprite, that smoothing destroys the hard pixel boundaries that define the art style. The result is softening, not improvement. The RetroTINK 5X already has excellent post-process sharpening options and integer scaling that preserves pixel grids. Adding the mClassic on top of integer-scaled 1080p output introduces pixel art softening that cannot be undone. Use the mClassic only for 3D games from the PlayStation 2, GameCube, or Dreamcast era where polygon edges benefit from smoothing and the loss of pixel definition is less noticeable.

Never Send 1440p Into the Dongle

Do not feed the mClassic 1440p from the RetroTINK 5X. The RetroTINK 5X can output 1440p natively, but the mClassic's HDMI input maxes at 1080p for processing. A 1440p input forces the mClassic into passthrough mode, bypassing both upscaling and edge smoothing. You lose the dongle's processing entirely. The correct input is always 1080p.

Green Mode Applies Smoothing Without Upscaling

mClassic retro mode with scaler means setting the dongle to its green LED mode, which applies edge smoothing without upscaling. The mClassic has three modes: blue LED (upscaling and smoothing), green LED (smoothing only), and off (passthrough). The green mode is useful when your display handles the upscale better than the mClassic does, or when you want the scaler's output resolution to reach the TV unchanged.

In a chain with a RetroTINK 5X outputting 1080p to a 4K TV, the green mode lets the RetroTINK's framebuffer scaling handle the 1080p to 4K conversion while the mClassic smooths polygon edges. This avoids double scaling. Double scaling artifacts appear when the scaler and the TV both attempt to upscale the same frame, creating a soft, processed look with visible ringing. The green mode prevents that by keeping the output resolution at 1080p and letting the TV finish the upscale.

Preserving Scanline Filters

The green mode is also the correct choice when using scanline filters. The RetroTINK 5X and OSSC both offer scanline filter interference that can be disrupted by the mClassic's upscaling. Scanline filters work by blanking alternating lines to simulate a CRT electron beam. The mClassic's blue mode upscale interpolates new lines, which fills in the blanked scanlines and destroys the effect. Green mode passes the scaler's output through without adding or removing lines, preserving the scanline filter.

Double scaling artifacts appear as a soft, processed look with ringing halos around high-contrast edges and a general loss of sharpness. This happens when the signal is scaled twice: once by the scaler to a resolution like 1080p, then again by the mClassic to 1440p, and then a third time by the TV to its native resolution. The result is a cascade of interpolation that removes fine detail.

To avoid double scaling, feed the mClassic the exact resolution your TV can accept natively. If your TV is 1080p, set the scaler to 1080p and use the mClassic's green mode for smoothing only. If your TV is 1440p, set the scaler to 1080p and use blue mode for the mClassic to upscale to 1440p, then let the TV display 1440p natively. If your TV is 4K, set the scaler to 1080p, use green mode, and let the TV upscale from 1080p to 4K. Never set the scaler to 480p or 720p and let the mClassic upscale from there, because the active image area is too small and the double scaling is severe.

Another artifact specific to the chain is chroma subsampling degradation. The mClassic uses HDMI 1.4b with HDCP 1.4. When it upscales 1080p to 1440p, it applies a 4:2:2 chroma subsampling that reduces colour resolution on red and blue edges. This is imperceptible on most games but visible on test patterns and on pixel art with saturated colours. The RetroTINK 5X and OSSC both support 4:4:4 chroma subsampling, so the loss of colour resolution is introduced by the mClassic itself. If colour purity matters, skip the mClassic entirely.

Measured Lag Is Negligible

Independent testing using a Time Sleuth latency test device, published by the community on Shmups Forum and verified by Digital Foundry, measures approximately 1 to 2 milliseconds of processing latency. This is imperceptible in gameplay, well below the 16.67ms frame time at 60Hz. For comparison, the OSSC adds less than one scanline of latency, or roughly 0.016ms at 60Hz. The RetroTINK 5X adds less than 1ms. The mClassic is the laggiest component in the chain, but at 1-2ms it does not affect feel-sensitive gameplay in rhythm games, shmups, or platformers.

Power Delivery Causes Dropouts

The real problem is power delivery. The mClassic draws power from the HDMI port, specified at 1.0A from a micro-USB 5V source. The RetroTINK 5X and OSSC both have HDMI output ports that supply power, but some units have under-spec ports that deliver less than the mClassic needs. The result is a signal dropout: the display goes black for 1-2 seconds as the HDMI handshake re-negotiates. This happens most often with the OSSC, whose HDMI output was designed before the mClassic existed and was not tested with a 1.0A draw. The fix is to power the mClassic via its micro-USB port using a separate USB power adapter. Do not rely on the scaler's HDMI port for power. If the dropout occurs every few minutes, connect the mClassic's micro-USB to a 5V, 1A USB wall charger.

The mClassic chain suits the gamer who owns a RetroTINK 5X or OSSC, plays primarily 3D games from the 5th and 6th console generations, and wants a slight edge-smoothing improvement on a 1440p or 4K display without buying a RetroTINK 4K. It also suits the capture and streaming hobbyist who needs the smoothing to reduce shimmer on polygon edges in a 1080p recording, as long as the mClassic is placed after the scaler and before the capture card.

Skip the mClassic chain if you play 2D pixel art games, use scanline filters, or already own a RetroTINK 4K that handles 4K output natively. Skip it if your display is 1080p, because the mClassic's 1440p output is wasted and the green mode's smoothing alone is rarely worth the power draw risk. The single thing that most often goes wrong is assuming the dongle works at any resolution and in any chain order, when it only works correctly at 1080p input with the scaler first and the dongle powered separately.