I have tested these models and I would like to share my experience with you. Both have many great functions and are very reliable and that makes the choice between Onkyo TX-NR676 vs Onkyo TX-NR686 so challenging.
These two receivers support a 7.2 channel setup. Both models support 4K at 60 Hz with HDR. TX-NR686 is THX certified, while TX-NR676 features VLSC that enhance the output audio signal. If we compare these two models in terms of sound, NR686 may be a bit better. The total power output comparison shows that TX-NR686 is more powerful (800 W) than TX-NR676 (700W).
Both models have 7in/2out HDMI ports. They support the wireless connection protocol - Bluetooth and Wi-Fi. It also lets you access various audio streaming services. They support the Chromecast technology. Both receivers support several zones. The audio balance can be achieved via the AccuEQ system that can tweak speakers automatically. Many customers that AccuEQ is easy to control.
Comparing Onkyo TX-NR676 vs TX-NR686 you will not see any major differences. The front display is very simple and it provides only the basic information. You will find two knobs on the left side (“Listening mode” and “Tone”) and four buttons. It also has a large knob on the right side. There are many buttons in the center part to choose the source or turn on and off the Bluetooth module. The front flap covers more buttons and inputs. The remote controller is very ergonomic. It has the most important functions, like volume tweaking, menu accessing, zone controlling, etc. Overall, there is nothing difficult about controlling these receivers. These two models are almost the same in terms of weight and size – NR686 is 14.9x17.1x6.8 inches, while NR676 is 14.8x17.1x6.8 inches. Their weight is 22 pounds.
Onkyo TX-NR686 overview
Onkyo TX-NR676 overview
The best receiver is Onkyo TX-NR676. Check Onkyo TX-NR676 price at Amazon