The Denon AVR-S640H vs Marantz NR1504 comparison proves that these receivers have many common features.
A significant difference between the receivers in the number of channels, Denon AVR-S640H has 5.2 versus 5.1 for Marantz NR1504. Regarding power, then AVR-S640H has such a W/Ohm ratio - 75/8, 100/6 when NR1504 has a power of 50/8, 60/6. The THD is the same and is 0.08%.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/32-bit for AVR-S640H and 192 KHz/24-bit for the NR1504. 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.
Only the Denon AVR-S640H can connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. The Denon AVR-S640H has support for AirPlay, AirPlay 2, and its competitor in our comparison - AirPlay. Spotify can be used on each receiver. The AVR-S640H can work with the audio stream from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, and the NR1504 can receive a content from Pandora, SiriusXM.
Only the Denon AVR-S640H 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. Dolby Vision technology found support only on the AVR-S640H.
The Denon AVR-S640H has 5/1 HDMI inputs/outputs versus 6/1 HDMI connectors of the Marantz NR1504. 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. The AVR-S640H has a built-in phono stage for connecting a vinyl player. An ECO mode is only available for the AVR-S640H. Both AVR-S640H and NR1504 can be configured using the Setup assistant.
None of the rivals equipped with Dolby Atmos multichannel audio decoder. The receivers do not support the surround sound technology DTS:X.