It makes sense comparing Yamaha RX-V685BL vs Yamaha RX-V683BL because they both are able to give some premium features.
Considered AV receivers have the same number of channels 7.2. And as for power, it is the same and equal to 90/8, 150/4. The THD is the same and is 0.06%.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 384 KHz/32-bit for RX-V685BL and Burr-Brown 192 KHz/24-bit for the RX-V683BL. Both the RX-V685BL and the RX-V683BL support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay. Only the RX-V683BL supports Spotify.
Both AV receivers support HDR10 technology (High dynamic range). Compared AV receivers retain the quality of 4K/60Hz signal when transmitting from a source to a TV or projector. HDMI signal transmission in standby mode is implemented in each of the devices. Both rivals can scale the resolution of the incoming HDMI signal. The HDR standard - Dolby Vision is supported by these receivers.
The Yamaha RX-V685BL has 5/2 HDMI inputs/outputs versus 6/1 HDMI connectors of the Yamaha RX-V683BL. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the RX-V685BL. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. Both models support the standard HDCP 2.2. These compared receivers have a built-in phono stage for connecting a vinyl player.
Each of the AV receivers from our review supports 2 Multi-room zones. A voice control is not available. It is also worth noting that the ECO mode is presented in each of the receivers. Both RX-V685BL and RX-V683BL can be configured using the Setup assistant.
Both devices have support for Dolby Atmos multichannel audio format. The surround sound technology DTS:X is supported by devices under review.