UHD MU6400

Released March 2017

Samsung's 2017 flat 4K LCD series with Active Crystal Colour, HDR support and Tizen, sold in 40-, 49-, 55- and 65-inch sizes.

Sizes: 40–65″
Panel: LED LCD
Refresh: –
HDR: HDR10+
HDMI 2.1: 0 of 3
Software: Tizen

What reviewers say

What Hi-Fi? praised the 40-inch model's natural colour, deep blacks and low gaming lag. FWD also liked colour and smart features, but found weak black levels on its 55-inch PLS sample. Both thought HDR impact and speakers limited; the different sizes should not be assumed to share contrast performance.

From whathifi.com and fwd.nl

Specifications

Report a wrong or missing spec

Display

Panel: LED LCD
Panel detail: Flat LED-backlit LCD. FWD found a PLS panel in its 55-inch European review sample; that panel subtype is not assigned across other sizes.
Resolution: 3840 × 2160 (4K)
HDR formats: HDR10, HLG, HDR10+
Peak brightness: FWD measured 307 nits on its 55-inch European sample; no maker peak-brightness figure is assigned.
Picture processing: Active Crystal Colour, UHD Dimming, Contrast Enhancer and Auto Motion Plus. Samsung's PQI 1500 is a processing label rather than native Hz; unpublished native refresh is omitted.

Sizes

Sizes: 40, 49, 55, 65″
Largest size: 65″

Gaming

HDMI ports: 3 (0 HDMI 2.1 at 4K 120 Hz+)
Variable refresh rate: None
Auto low latency mode: No
HDMI detail: Three HDMI inputs with ARC and HDMI-CEC; component/shared composite inputs also provided.
Input lag: 21.3 ms in Game Mode on the 40-inch What Hi-Fi? sample; 17.7 ms in Game Mode and 91.1 ms in Film Mode on the 55-inch FWD sample.
Game features: Manual Game Mode; no variable refresh or automatic low-latency switching.

Smart TV and sound

Smart TV platform: Tizen
Processor: UHD Up-Scaling picture engine; quad-core smart processor
Speakers: 20 W, 2.0 channels
eARC: No
Wi-Fi: Built-in Wi-Fi
Speaker detail: Two-channel down-firing bass-reflex speakers with 20 W total output.
Audio features: Dolby Digital Plus, DTS, Multiroom Link and Bluetooth audio.
Software updates: Tizen 3.0 in Samsung's developer model table. Samsung confirmed HDR10+ across its 2017 UHD lineup in December 2017; compatible firmware and content are required. Original app availability is not guaranteed today.
TV tuners: DVB-T2/C/S2 digital and analogue tuners, with CI+ 1.3.
USB: Two USB ports with media playback, recording and time shift.
Ethernet: Ethernet LAN port.
Optical audio out: Optical digital audio output; FWD found no 3.5 mm headphone socket on its 55-inch European unit.

Design and power

Size: Width × height × depth without stands, from the UK manual: 40-inch 903.7 × 519.8 × 54.2 mm; 49-inch 1099.4 × 638.7 × 54.8 mm; 55-inch 1235.2 × 715.1 × 54.8 mm; 65-inch 1456.1 × 840.4 × 54.5 mm. Configuration weights exclude stands.
Stand: Fixed Y-shaped stand with no swivel. UK manual with-stand weights are 10.5, 16.0, 19.0 and 26.7 kg respectively; this overrides the online table's 10.6 and 28.3 kg for 40 and 65 inches.
In the box: TM1750A Smart Remote and TM1240A standard remote for UK/Ireland, batteries, power cable, manual and analogue breakout cable.

Sizes

Size	Model	Weight without stand
40″	UE40MU6400UXXU	9.2 kg
49″	UE49MU6400UXXU	14 kg
55″	UE55MU6400UXXU	16.9 kg
65″	UE65MU6400UXXU	23.2 kg

Pros and cons

Pros

4K resolution with HDR10, HLG and updated HDR10+ support
Three HDMI inputs and two USB ports
Built-in Wi-Fi and Bluetooth audio

Cons

No HDMI 2.1 or variable refresh support
No Dolby Vision support
Original online apps may no longer be available

Closest rivals

Model	Sizes	Panel	Refresh	HDR	HDMI 2.1	Software	Released
HisenseA7S	43–65″	LED LCD	60 Hz	Dolby Vision, HDR10+	0 of 3	VIDAA	Jan 2026
PanasonicVIERA AX902	55–65″	LED LCD	–	None	0 of 4	my Home Screen	2014
PanasonicVIERA CX802	40–65″	LED LCD	–	HDR10	0 of 3	my Home Screen	2015

Sources

Photo: Maker front view retains original Ultra HD and UHD TV screen badges; no clean render was available from the exact support page.

Spot a mistake? Tell us