It’s strongly recommended to compare different receivers if you want to choose the best one: Denon HEOS AVR vs Pioneer Elite SC-LX704.
The number of channels for receivers is different - 5.1 versus 9.2, respectively, for devices. In terms of power, there are differences, the HEOS AVR has such a ratio W/Ohm - 50/8, 65/6, while the Elite SC-LX704 has a power of 135/8. The value of total harmonic distortion is also different, and for the HEOS AVR it is 0.05%, but for the Elite SC-LX704 it is 0.08%. The Bi-amping function is implemented only in the Pioneer Elite SC-LX704. Both Denon HEOS AVR and Pioneer Elite SC-LX704 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Wireless Internet access via WIFI is possible on both units. Each of the receivers has a Bluetooth connector. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Denon HEOS AVR works with Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, but the Pioneer Elite SC-LX704 works with Deezer, TIDAL, Pandora. The quality of 4K/60Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the HEOS AVR and the Elite SC-LX704. Video scaling is only possible with the Elite SC-LX704. Operation with the Dolby Vision is only possible with the Elite SC-LX704.
The number of HDMI inputs/outputs varies depending on the receiver, the HEOS AVR has 4/1, and the Elite SC-LX704 has 7/3. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the HEOS AVR and the Elite SC-LX704. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. The HEOS AVR has support for the standard HDCP 2.2, compared to the Elite SC-LX704, which supports the standard HDCP 2.3. In the presence of a built-in phono stage for connecting a vinyl player only at Pioneer Elite SC-LX704. For voice control in the HEOS AVR is used Amazon Alexa, Google Assistant, but in the Elite SC-LX704 is used Amazon Alexa. There is an ECO mode in neither AV receiver. The Pioneer Elite SC-LX704 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the Elite SC-LX704. Only in the Elite SC-LX704 realized a DTS:X surround technology.