The Denon AVR-S640H vs Onkyo TX-NR585 comparison will be extremely helpful for people who want to get a great, powerful receiver with many functions.
The number of channels for receivers is different - 5.2 versus 7.2, respectively, for devices. In terms of power, there are differences, the AVR-S640H has such a ratio W/Ohm - 75/8, 100/6, while the TX-NR585 has a power of 80/8, 170/6. A common feature for devices is the same total harmonic distortion - 0.08%.
The manufacturer installed different DACs, the AVR-S640H received the model 192 KHz/32-bit, but the TX-NR585 is equipped with AK4458 384 KHz/32-bit. The Bi-amping function is implemented only in the Onkyo TX-NR585. Both Denon AVR-S640H and Onkyo TX-NR585 can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Each of the receivers has a Bluetooth connector. The contenders have differences in the supported services from Apple - AirPlay, AirPlay 2 versus AirPlay respectively. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Denon AVR-S640H works with Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, but the Onkyo TX-NR585 works with Deezer, TIDAL, Pandora, TuneIn Radio. 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 AVR-S640H and the TX-NR585. None of the devices can increase the resolution of the incoming video signal. Each of the participants of the comparison has a Dolby Vision.
The number of HDMI inputs/outputs varies depending on the receiver, the AVR-S640H has 5/1, and the TX-NR585 has 7/1. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the AVR-S640H and the TX-NR585. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. AVR-S640H and TX-NR585 support the standard HDCP 2.2. Like most receivers, our models have a built-in phono stage for connecting a vinyl player. For voice control in the AVR-S640H is used Amazon Alexa, Google Assistant, Siri, Josh.AI, but in the TX-NR585 is used Google Assistant. There is an ECO mode in AVR-S640H. The Denon AVR-S640H and the Onkyo TX-NR585 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the TX-NR585. Only in the TX-NR585 realized a DTS:X surround technology.