Pioneer VSX-531 vs Marantz NR1403 comparison definitely makes sense.
Considered AV receivers have the same number of channels 5.1. Regarding power, then VSX-531 has such a W/Ohm ratio - 80/8, 140/6 when NR1403 has a power of 50/8, 80/6. The THD is the same and is 0.08%.
Competitors' digital to analog converter (DAC) is identical to 192 KHz/24-bit. None of the models support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Both models do not have WI-FI support. Rivals from our review have Bluetooth support. Each of these units does not support Apple Music. Competitors do not have built-in Spotify service.
Only the Pioneer VSX-531 has support for High dynamic range (HDR). HDMI signal transmission in standby mode is implemented in each of the devices. Both competitors are not able to scale the HDMI signal. The HDR standard - Dolby Vision is not supported by these receivers.
The Pioneer VSX-531 has 4/1 HDMI inputs/outputs versus 6/1 HDMI connectors of the Marantz NR1403. The HDMI Audio Return Channel (ARC) feature supports both devices. Unfortunately, HDMI eARC is not available on monitored devices. 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. Receivers do not have a built-in phono stage for connecting a vinyl player. A voice control is not available. An ECO mode is only available for the VSX-531. Unfortunately, the setup assistant is not available in each of the models.
None of the rivals equipped with Dolby Atmos multichannel audio decoder. The receivers do not support the surround sound technology DTS:X.