It makes sense comparing Denon AVRX4400H vs Marantz SR6014 because they both are able to give some premium features.
Considered AV receivers have the same number of channels 9.2. Regarding power, then AVRX4400H has such a W/Ohm ratio - 125/8, 165/6 when SR6014 has a power of 110/8, 185/6. The THD is 0.05% for the AVRX4400H but 0.08% for the SR6014.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/24-bit for AVRX4400H and AK4458 384 KHz/32-bit for the SR6014. Both the AVRX4400H and the SR6014 support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay, AirPlay 2. Spotify can be used on each receiver. The AVRX4400H can work with the audio stream from Deezer, TIDAL, Pandora,iHeart Radio, Sirius XM, Sound Cloud, Napster, and the SR6014 can receive a content from Deezer, TIDAL, Pandora, TuneIn Radio, iHeart Radio. 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. Both rivals can scale the resolution of the incoming HDMI signal. The HDR standard - Dolby Vision is supported by these receivers.
Each receiver has 8/3 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. HDMI eARC is available in each model. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The AVRX4400H supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the SR6014. These compared receivers have a built-in phono stage for connecting a vinyl player.
The AVRX4400H supports 3 Multi-room zones, versus 2 for the SR6014. Supported voice control technologies are identical - Amazon Alexa, Google Assistant, Siri, Josh.AI. It is also worth noting that the ECO mode is presented in each of the receivers. Both AVRX4400H and SR6014 can be configured using the Setup assistant.
Both devices have support for Dolby Atmos multichannel audio format. The surround sound technology DTS:X is supported by devices under review.