$ Bottom line: Which one is better?
Bottom line: Samsung Q9FN is better.
In this review of Sony X900 F Vs Samsung Q9FN, Samsung Q9FN is better because it has a better dark room performance as it has a better local dimming & better black uniformity, has better reflection handling.
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: DESIGN
Stand; the two TVs have stands
Wall mount; Sony X900F has VESA 300×300 whereas Samsung Q9FN has VESA 400×400
Borders; Sony X900F has 0.35” (0.9cm) whereas Samsung Q9FN has 0.43” (1.1cm)
Max thickness; Sony X900F is 2.76” (7.0cm) whereas Samsung Q9FN is 1.61” (4.1cm)
Max temperature; Sony X900F has 91oF (33oC) whereas Samsung Q9FN has 97oF (36oC)
Average temperature; Sony X900F has 87oF (30oC) whereas Samsung Q9FN has 84oF (29oC)
Bottom line: Samsung Q9FN is better
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: PICTUREE QUALITY
Native contrast; Sony X900F has 5089:1 whereas Samsung Q9FN has 6055:1
Local dimming; the two TVs have local dimming
SDR real scene peak brightness; Sony X900F has 578cd/m2 whereas Samsung Q9FN has 667cd/m2
HDR real scene peak brightness; Sony X900F has 894cd/m2 while Samsung Q9FN has 908cd/m2
Gray uniformity; Sony X900F has 7.5 whereas Samsung Q9FN has 6.7
50% std. Dev; Sony X900F has 4.335% whereas Samsung Q9FN has 3.553%
50% DSE; Sony X900F has 0.165% while Samsung Q9FN has 0.236%
Viewing angle; Sony X900F has 5.2 while Samsung Q9FN has 5.4
Native std. Dev; Sony X900F has 0.923% while Samsung Q9FN has 0.537%
Total reflections; Sony X900F has 3.5% while Samsung Q9FN has 1.4%
Pre-calibration; Sony X900F has 8.9 whereas Samsung Q9FN has 7.4
White balance dE; Sony X900F has 1.66 whereas Samsung Q9FN has 2.88
Color dE; Sony X900F has 1.60 while Samsung Q9FN has 3.39
Color temperature; Sony X900F has 6537K whereas Samsung Q9FN has 6145K
Post calibration; Sony X900F has 9.5 whereas Samsung Q9FN has 9.4
White balance dE; Sony X900F has 0.13 whereas Samsung Q9FN has 0.15
Color dE; Sony X900F has 1.33 whereas Samsung Q9FN has 1.77
Color temperature; Sony X900F ha 6495K while Samsung Q9FN has 6515K
Bottom line: Samsung Q9FN is better
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: MOTION
100% response time; Sony X900F has 10.2ms while Samsung Q9FN has 15.5ms
Flicker-free; the two TVs don’t have.
BFI; the two TVs have optional BFI
Motion interpolation; the two TVs have motion interpolation 30fps 60fps
Variable refresh rate; Samsung Q9FN has FreeSync
Bottom line: the two TVs have the same motion features
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: INPUTS
Input lag; Sony X900F has 8.4 whereas Samsung Q9FN has 9.1
Supported resolutions; Sony X900F has 9.6 whereas Samsung Q9FN has 8.8
Total inputs; the two TVs have 4 HDMI, 3 USB, 1 Digital optical audio out, 1 tuner (cable/Ant0 and 1 Ethernet. Sony X900F has 1 IR in, 1 composite in and 1 Analog audio out 3.5.
Inputs specifications; each TV has HDR10, HLG, HDMI 2.0 Full bandwidth, CEC, HDCP 2.2 and Wi-Fi support. Sony X900F has Dolby vision, USB 3.0 and Variable Analog audio out while Samsung Q9FN has HDR10+
Audio pass-through; each TV has ARC, 5.1 Dolby Digital and DTS
Bottom line: Sony X900F is better
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: SOUND QUALITY
Low-frequency extension; Sony X900F has 95.14Hz whereas Samsung Q9FN has 113.14Hz
Max; Sony X900F has 90.0dB SPL whereas Samsung Q9FN has 88.4dB SPL
Weighted THD @ Max; Sony X900F has 9.787 whereas Samsung Q9FN has 0.892
IMD @ Max; Sony X900F has 72.21% while Samsung Q9FN has 1.18%
Bottom line: Samsung Q9FN is better
Sony X900F Vs Samsung Q9FN/Q9/Q9F QLED: SMART FEATURES
Smart OS; Sony X900F operate on Android TV version 7.0 whereas Samsung Q9FN is on Tizen version 2018
Interface; Sony X900F has average ease of use while Samsung Q9FN is easy and not smooth.
Ad-free; the two TVs have ads
Apps and features; the two TVs have apps and features
Remote; Sony X900F has large whereas Samsung Q9FN has small.
TV controls; the two TVs have TV controls.
Bottom line: Samsung Q9FN is better
Conclusion
In this review, Samsung Q9FN is a better TV as it has a better dark room performance. It equally has a better local dimming, black uniformity and reflection handling.