Having had an opportunity to test Denon AVR-S540BT vs Onkyo TX-SR373, 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 5.1, respectively, for devices. In terms of power, there are differences, the AVR-S540BT has such a ratio W/Ohm - 70/8, 90/6, while the TX-SR373 has a power of 135/6. The value of total harmonic distortion is also different, and for the AVR-S540BT it is 0.08%, but for the TX-SR373 it is 0.06%.
The manufacturer installed different DACs, the AVR-S540BT received the model 192 KHz/32-bit, but the TX-SR373 is equipped with 192 KHz/24-bit. None of the compared opponents supports Bi-amping. In the considered devices there is no function transmitting an audio signal directly to the amplifier and bypasses any DSP processing.
Wireless connection to the Internet via WIFI can not be performed on these receivers. Each of the receivers has a Bluetooth connector. Support for Apple Music Services not implemented. The AVR-S540BT has access to the Spotify service.
Support for the HDR function can only boast of each of the AV receivers. 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-S540BT and the TX-SR373. None of the devices can increase the resolution of the incoming video signal. Operation with the Dolby Vision is only possible with the AVR-S540BT.
The number of HDMI inputs/outputs varies depending on the receiver, the AVR-S540BT has 5/1, and the TX-SR373 has 4/1. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the AVR-S540BT and the TX-SR373. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. AVR-S540BT and TX-SR373 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-S540BT. The Denon AVR-S540BT 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.