Having had an opportunity to test Yamaha RX-V685BL vs Yamaha RX-S602, I’d like to share my impression here to facilitate your choice of a new AV receiver.
The number of channels for receivers is different - 7.2 versus 5.1, respectively, for devices. In terms of power, there are differences, the RX-V685BL has such a ratio W/Ohm - 90/8, 150/4, while the RX-S602 has a power of 80/8, 125/6. The value of total harmonic distortion is also different, and for the RX-V685BL it is 0.06%, but for the RX-S602 it is 0.08%.
Competitive models use the same DAC. Each of the compared opponents supports Bi-amping. Both Yamaha RX-V685BL and Yamaha RX-S602 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
These units have the same Wi-Fi modules. Each of the receivers has a Bluetooth connector. The contenders have differences in the supported services from Apple - AirPlay versus AirPlay, AirPlay 2 respectively. The RX-S602 has access to the Spotify service.
The HDR10 function is present in each of the rivals. The quality of 4K/60Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the RX-V685BL and the RX-S602. Video scaling is only possible with the RX-V685BL. Operation with the Dolby Vision is only possible with the RX-V685BL.
The number of HDMI inputs/outputs varies depending on the receiver, the RX-V685BL has 5/2, and the RX-S602 has 4/1. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is only supported by the RX-V685BL. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. The RX-V685BL has support for the standard HDCP 2.2, compared to the RX-S602, which supports the standard HDCP 2.3. In the presence of a built-in phono stage for connecting a vinyl player only at Yamaha RX-V685BL.
Ability to create 2 Multi zones inherent in both AV receivers. There is an ECO mode in either AV receiver. The Yamaha RX-V685BL and the Yamaha RX-S602 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the RX-V685BL. Only in the RX-V685BL realized a DTS:X surround technology.