An affordable AV receiver is always a good option to consider, so Onkyo TX-RZ840 vs Denon AVR-X1400H comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Onkyo TX-RZ840 has 9.2 versus 7.2 for Denon AVR-X1400H. Regarding power, then TX-RZ840 has such a W/Ohm ratio - 180/6 when AVR-X1400H has a power of 80/8, 120/6. The THD is the same and is 0.08%.
Characteristics of digital to analog converter (DAC) are different, AKM 384 KHz/32-bit for TX-RZ840 and 192 KHz/24-bit for the AVR-X1400H. Both the TX-RZ840 and the AVR-X1400H support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Both models have the ability to connect to the Internet via WI-FI. 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 TX-RZ840 can work with the audio stream from Deezer, TIDAL, Pandora, TuneIn Radio, and the AVR-X1400H can receive a content from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud. 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 competitors are not able to scale the HDMI signal. The HDR standard - Dolby Vision is supported by these receivers.
The Onkyo TX-RZ840 has 7/2 HDMI inputs/outputs versus 6/1 HDMI connectors of the Denon AVR-X1400H. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the TX-RZ840. 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 TX-RZ840 has a built-in phono stage for connecting a vinyl player.
Each of the AV receivers from our review supports 3 Multi-room zones. The TX-RZ840 supports voice control via Google Assistant, and the AVR-X1400H - Amazon Alexa, Google Assistant, Siri, Josh.AI. An ECO mode is only available for the AVR-X1400H. Both TX-RZ840 and AVR-X1400H 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.