The TCL 6 Series (R617/R615) is a very good 4k TV for a wide range of usages. It has good dark scene performance due to the full-array local dimming and high native contrast so blacks appear deep even in a dark room. It is also great for HDR, as it has a great brightness. Although it can produce a wider color gamut than Rec. 709, it isn't as wide as other great HDR TVs. It also has an excellent low input lag for gamers, and unlike last year's TCL P607 it can flicker the backlight to clear up fast motion and interpolate low frame rate content.
The TCL 6 Series is also known as the R615 or R617 depending on the manufacturer variant.
The design of the TCL 6 Series is decent, similar to most TCL TVs we have tested. The stand is wide but very stable, and the TV feels slightly bulky due to the square design of the TV's bezel. It will not stand out as a premium TV but is quite functional.
Like most TCLs, the TCL 6 Series has a stand that is nearly the full width of the TV. You will need a very wide table to put it on. It is made of metal and feels strong and sturdy. This change in material is nice from the plastic feel of older TCL models.
Footprint of the 55" TV stand: 47.8" x 10.6"
The legs can also be reversed, in which case the stand measures 28.5" x 10.6".
The rear of the TV is simple. The top half is metallic and the body is plastic.
There is no cable management, so it can look a bit messy for those who enjoy clean setups with hidden cables.
The borders of the TCL 6 Series look decent. They are metallic and have the same finish as the stand legs.
The TCL 6 Series is comprised of two sections: the electronics compartment and the panel section which is square and has a bulky feel to it. Even though the overall thickness is not bad, it will stick out a little if wall mounted
The TCL 6 Series stays quite cool. In fact, it scored one of the lowest average temperatures of the TVs we tested in 2017-8.
It has two big vents, one on the bottom and one in the back allowing the temperature on the screen to be fairly uniform.
The build quality of the TCL 6 Series feels decent. There are no loose panels or gaps, and the TV seems to have a solid construction.
We have received many reports of varying gray uniformity issues between units, which may be indicative of the build quality or quality control.
The TCL 6 Series has very good picture quality. The native contrast is excellent, and it has a decent local dimming feature that can further boost the black levels. While blacks aren't as deep as the P607, this is still a great TV for dark room viewing. The TV is much brighter than last year's P607, this is especially noticeable in HDR. Gray uniformity is decent, but we have received reports from many people with much worse uniformity. Like the P607, the viewing angle is bad. Out of the box, colors have good accuracy, and the calibration is easy and fast with the TCL app. Decent color volume, but deep dark colors aren't displayed very well.
The TV has amazing contrast. It matches many of the high-end TVs we have tested. Although it does not reach the contrast levels of the TCL P607/605 models it certainly follows their legacy of excellent contrast.
The contrast increases with local dimming since the full array panel manages to darken the blacks without sacrificing much brightness. This is great for dark room performance.
The local dimming on the TCL R615/617 series is decent, and it can produce deeper dark scenes which is very noticeable especially when viewed in a dark room.
On the other hand, there is some obvious clouding around the moving objects. This is because of the inherent limitations of FALD technology and should not worry most people.
Update: The text has been updated to better explain why we see some clouding.
Great SDR peak brightness, it performs well in a bright room. The TV boosts the bright sections of the screen when other areas are dimmer. This is shown by how the smaller window tests are brighter than the larger ones.
This is an improvement from last year's TCL P605/607 and it is much better than the brightness of competing TVs like the Samsung NU7100 and Vizio M Series 2017. It's also a bit brighter than the newer TCL 6 Series 2019 R625.
The TCL 6 Series has great HDR peak brightness. Bright highlights in HDR content will be shown fairly bright, very close to the level of 1000-4000 cd/m² they're intended to be.
Overall the HDR brightness is much better than last year's TCL P605/607 which is great.
Unfortunately, the TCL 6 Series we tested has mediocre uniformity. There is noticeable dirty screen effect throughout the screen, and the corners are noticeable darker than the rest of the screen. This varies between units, so your results may be better than ours.
The viewing angle is poor. Blacks and colors shift rapidly as you move away from the front, and the brightness drops quickly as the angle increases a few degrees.
As with most TCLs we have reviewed it is most suitable for a narrow viewing environment.
The Sony X720E is a better choice for a wide viewing angle.
The black uniformity of the TCL 6 Series is good. Although there is some clouding in the native black uniformity, the performance improves when local dimming is enabled. This reduces clouding only around the test cross.
The TCL 6 Series has a semi-gloss finish that works well in diffusing reflections across the screen. However, when viewed in a bright room the reflections may be somewhat distracting especially if the source is facing the TV.
This model has better reflection handling than the newer TCL R625.
Out of the box, the TCL 55R617 has good color accuracy. The color temperature is quite warm, so everything is slightly red/yellow. Gamma already follows our target well. White balance and color dE are low enough that most people won't notice much of a difference.
The TCL 6 Series has to calibrated with the TCL app. Calibration is very easy to do and both the white balance and the CMS respond very well to calibration. The blue dE was not as easy to correct, but remains accurate.
Post calibration, the TV is one of the most accurate TVs on the market. Gamma follows the target curve perfectly, and white balance and color dE are nearly perfect. The overall color temperature is a bit warm still, but very close to the target 6500K.
See our recommended settings here.
Lower resolution 480p content looks good and is displayed without any obvious issues.
There are some artifacts visible with 4k content due to the sub-pixel dimming. This performs similarly to the P607 (see here), but shouldn't be an issue for most people and is mostly noticeable when used as a PC monitor.
This type of dithering is uncommon, and is only seen on some TCL TVs, including the S517 and R617. Most people won't notice it much, but occasionally it causes artifacts when it interferes with spatial dithering in games such as this green or purple shadow. (Note: the images are from the S517, but we expect them to be the same on the 6 Series.)
Update 29/05/2018: We have received a report that the 49" S515/S517 has similar crosshatching to the S405, as seen here and we expect this to be the same in the R615/R617. This will bother some people especially when used as a PC Monitor.
The TCL 6 Series has a good color gamut, but slightly worse than last year's P607. It supports a wide color gamut, but it isn't as wide as other HDR TVs. HDR will look good, but bright outdoor scenes will lack some detail due to the TV's limited green reproduction.
Note that for this test, a PC was used as a pattern generator. Like many other TCL TVs, the TV detects the PC from the AVI infoframe and automatically switches to a PC mode which behaves a little bit differently. Using a HDFury Integral to mask the AVI infoframe results in a color gamut in the same ballpark, but slightly lower at around 65.8% Rec. 2020 uv.
The TCL 6 Series has decent color volume. In the P3 volume, it covers the gamut well; this is a great improvement over the TCL P607. In both color volumes, the darker colors are not displayed very well, and blues don't get very bright.
The performance is comparable to the 2017 TCL P605/P607 model although not quite as good. There is some small banding visible in dark reds, greens and grays, but no major banding in any color. Those minor imperfections are not likely to ruin a good HDR movie watching experience.
There is no image retention on this TV. As always this is good news for gamers and PC users who might use this TV as a monitor.
We don't expect VA panels to experience permanent image retention, as the VA panel in our long-term test appears immune.
The TCL 6 Series has good motion handling. The response time is great, and motion appears clear and relatively flicker-free due to the high backlight refresh rate. It can reduce the backlight frequency to help reduce stutter, but this results in some strange duplications. Movies look great and are judder-free.
Very good response time. Most of the blur in the above photo is due to persistence. Pixel response is similar to the P607. There is almost no overshoot in any of the transitions.
The TCL 55R617 mainly dims the backlight through PWM, although there is some amplitude dimming as well. The backlight flicker is hardly noticeable, as it flickers at 480Hz, a significant improvement over the 120 Hz flicker on the P607.
The TCL 6 Series has a new optional black frame insertion feature that can adjust the backlight flicker to help clear up motion by introducing flicker.
This can be enabled by going to Options->Advanced Picture Settings and turning LED Motion Clarity On.
The TV can flicker as low as 60 Hz, even in game mode, but there are some strange results. It appears to flicker each color individually, resulting in visible duplications of different colors, as seen here. This is also noticeable when moving around with BFI enabled.
The TV can interpolate lower frame rate content as high as 60 fps. Motion can look a little strange to some people when enabled, this is commonly known as the Soap Opera Effect. This does not work when connected to a PC, and there is no way to bypass this as this TCL automatically detects when it is connected to a PC.
Motion interpolation is new this year on the TCL R617, and it can be enabled by going to the Advanced picture settings menu, and setting Action Smoothing to either Off, Low, Medium or High.
The TCL 6 Series can display most content without stutter, but there is some noticeable stutter when playing 24p content - like Blu-ray movies. This is mostly noticeable in wide-panning shots.
The TV is judder free when playing native 24p content from a Blu-ray player. To remove judder from other sources, Natural cinema must be enabled in the Advanced Picture Settings menu. This is a significant improvement over all other TCL TVs we have reviewed.
The TCL 6 Series doesn't support any of the Variable Refresh Rate technologies like AMD Freesync. We tested on a PC with an AMD Radeon RX 580.
The TCL 6 Series has excellent low input lag, as long as Game mode is enabled. The input lag is extremely low, great for console gaming. When in PC mode, Game mode must be enabled to get the lowest input lag.
Like the 2018 Samsung TVs we have tested, there is no DTS passthrough, so it is recommended to connect your Blu-ray player or game console directly to your receiver if you want surround sound on movies.
Update 01/09/2019: We retested the DTS passthrough with the new firmware and it works properly thus giving you more options regarding your external device connectivity.
The TCL 6 Series has excellent low input lag, as long as Game mode is enabled. With Game mode disabled, input lag is extremely high. 1080p and 4k input lag is very similar. The TV is a 60Hz panel, as such 120Hz input is not supported.
For use as a PC monitor, the TV automatically detects when it is connected to a PC. If it doesn't automatically detect it, changing the input label to Computer will enable PC Mode. For the lowest input lag in PC mode, Game mode must also be enabled.
The TV supports most resolutions without issue. For use as a PC Monitor, PC mode must be enabled; either by the TV's auto-detection or by changing the input label to Computer. The TV must be in PC mode for chroma 4:4:4 to work.
All of the inputs are directed out the side. There is an included mini break out cable for composite input, but no component input.
Unlike the P607, there is no headphone output on the remote. To connect headphones, the audio output on the side of the TV is the only option.
Unlike the P607, there is no headphone output on the remote. To connect headphones, the audio output on the side of the TV is the only option.
For the audio return channel to work, CEC must be enabled in Settings -> System -> Control other devices (CEC) -> ARC (HDMI 3).
For 5.1 passthrough on the ARC, the Audio Mode must be set to Auto in the Settings -> Audio menu, with S/PDIF and ARC set to "Dolby D, DTS". With other settings no sound was getting passed through to our receiver, not even stereo PCM.
DTS passthrough doesn't work, which is unexpected since it did on last year's P607.
Update 06/05/2018: To support HDR on HDMI ports connected to an Xbox One, the HDMI ports must be manually set to HDMI 2.0 as the Auto setting will not automatically switch to HDMI 2.0 due to a detection issue.
Update 01/09/2019: We retested the DTS passthrough with the new firmware and now it works properly.
The TCL 6 Series has a sub-par sound quality. This TV does get loud enough for most situations and produces clear dialogs. However, it doesn't produce much bass and doesn't have a room correction system either. For a better sound, dedicated speakers or soundbars are recommended (see our recommendations for the best budget soundbars).
The frequency response is sub-par. The LFE (Low-frequency extension) is at 143Hz, which means this TV won't produce any thump or rumble, and not a lot of body and punch either. The response above the TV's LFE is relatively well-balanced, which is important for producing clear dialogs. However, since this TV doesn't have a room correction system, it wasn't able to remove the mode of our test room around 200Hz. Additionally, it gets loud enough for most situations, and doesn't produce an excessive amount of compression artifacts under heavier loads.
The distortion performance is about average. The overall amount of harmonic distortion is within good limits at 80dB SPL, but slightly elevated at max volume. This TV also produces high amounts of intermodulation distortion, which could translate to a less transparent treble. Both the effect will be subtle and won't be noticeable to most users.