Having had an opportunity to test Denon AVR-X540BT vs Onkyo TX-NR616, I’d like to share my impression here to facilitate your choice of a new AV receiver.
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-X540BT has such a ratio W/Ohm - 70/8, 90/6, while the TX-NR616 has a power of 160/6. A common feature for devices is the same total harmonic distortion - 0.08%.
The manufacturer installed different DACs, the AVR-X540BT received the model 192 KHz/24-bit, but the TX-NR616 is equipped with Burr-Brown 192 KHz/24-bit. The Bi-amping function is implemented only in the Onkyo TX-NR616. Both Denon AVR-X540BT and Onkyo TX-NR616 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Wireless Internet connection via WIFI is only possible with TX-NR616. Each of the receivers has a Bluetooth connector. Support for Apple Music Services not implemented. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Denon AVR-X540BT works with TIDAL, Pandora, but the Onkyo TX-NR616 works with Last.fm, AUPEO, Simfy, vTuner.
Support for the HDR function can only boast of the AVR-X540BT. 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-X540BT and the TX-NR616. Video scaling is only possible with the TX-NR616. Operation with the Dolby Vision is only possible with the AVR-X540BT.
The number of HDMI inputs/outputs varies depending on the receiver, the AVR-X540BT has 5/1, and the TX-NR616 has 8/2. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the AVR-X540BT and the TX-NR616. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. AVR-X540BT and TX-NR616 support the standard HDCP 2.2. Unlike most receivers, our models do not have a built-in phono stage for connecting a vinyl player. Voice control of the basic functions of the receiver is not realized in both models. There is an ECO mode in AVR-X540BT. The Denon AVR-X540BT can be properly configured using the setup assistant.
Generally no support for a Dolby Atmos multichannel audio format. A DTS:X surround technology is not supported by devices from our comparison.