It makes sense comparing Marantz NR1504 vs Denon AVR-S950H because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Marantz NR1504 has 5.1 versus 7.2 for Denon AVR-S950H. Regarding power, then NR1504 has such a W/Ohm ratio - 50/8 20Hz-20KHz, 60/6 1KHz when AVR-S950H has a power of 90/8 20Hz-20KHz, 125/6 1KHz. The THD is the same and is 0.08%.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/24-bit for NR1504 and AKM 192 KHz/32-bit for the AVR-S950H. 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-S950H can connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. The Marantz NR1504 has support for AirPlay, and its competitor in our comparison - AirPlay, AirPlay 2. Spotify can be used on each receiver. The NR1504 can work with the audio stream from Pandora, SiriusXM, and the AVR-S950H can receive a content from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, Mood Mix. HDMI signal transmission in standby mode is implemented in each of the devices. The AVR-S950H can scale the input HDMI signal, unlike the NR1504. Dolby Vision technology found support only on the AVR-S950H.
The Marantz NR1504 has 6/1 HDMI inputs/outputs versus 8/2 HDMI connectors of the Denon AVR-S950H. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the AVR-S950H. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The NR1504 supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the AVR-S950H. The AVR-S950H has a built-in phono stage for connecting a vinyl player. An ECO mode is only available for the AVR-S950H. Both NR1504 and AVR-S950H can be configured using the Setup assistant.
Only the AVR-S950H has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the AVR-S950H.
The Denon AVR-S950H is better receiver in this comparison. Check Denon AVR-S950H price