It makes sense comparing Yamaha RX-V685BL vs Marantz NR1509 because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Yamaha RX-V685BL has 7.2 versus 5.2 for Marantz NR1509. Regarding power, then RX-V685BL has such a W/Ohm ratio - 90/8, 150/4 when NR1509 has a power of 50/8, 60/6. The THD is 0.06% for the RX-V685BL but 0.08% for the NR1509.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 384 KHz/32-bit for RX-V685BL and 192 KHz/24-bit for the NR1509. Only the RX-V685BL supports Bi-amping feature. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
WI-FI modules have the same characteristics: 2.4/5GHz. Rivals from our review have Bluetooth support. The Yamaha RX-V685BL has support for AirPlay, and its competitor in our comparison - AirPlay, AirPlay 2. Only the NR1509 supports Spotify. 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. The RX-V685BL can scale the input HDMI signal, unlike the NR1509. The HDR standard - Dolby Vision is supported by these receivers.
The Yamaha RX-V685BL has 5/2 HDMI inputs/outputs versus 7/1 HDMI connectors of the Marantz NR1509. 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. It is also worth noting that the ECO mode is presented in each of the receivers. Both RX-V685BL and NR1509 can be configured using the Setup assistant.
Only the RX-V685BL has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the RX-V685BL.