Having had an opportunity to test Marantz NR1608 vs Onkyo TX-NR545, I’d like to share my impression here to facilitate your choice of a new AV receiver.
AV receivers under review have the same number of channels. In terms of power, there are differences, the NR1608 has such a ratio W/Ohm - 50/8, 70/6, while the TX-NR545 has a power of 100/6. The value of total harmonic distortion is also different, and for the NR1608 it is 0.05%, but for the TX-NR545 it is 0.08%.
The manufacturer installed different DACs, the NR1608 received the model AK4458 384 KHz/32-bit, but the TX-NR545 is equipped with Hi-Grade 384 KHz/32-bit. Each of the compared opponents supports Bi-amping. Both Marantz NR1608 and Onkyo TX-NR545 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
These units have the same Wi-Fi modules. 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 Marantz NR1608 works with Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, but the Onkyo TX-NR545 works with Tunein Radio.
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 NR1608 and the TX-NR545. Video scaling is only possible with the NR1608. Operation with the Dolby Vision is only possible with the NR1608.
The number of HDMI inputs/outputs varies depending on the receiver, the NR1608 has 8/1, and the TX-NR545 has 6/1. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the NR1608 and the TX-NR545. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. NR1608 and TX-NR545 support the standard HDCP 2.2. Unlike most receivers, our models do not have a built-in phono stage for connecting a vinyl player.
Ability to create 2 Multi zones inherent in both AV receivers. There is an ECO mode in NR1608. The Marantz NR1608 and the Onkyo TX-NR545 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available both models. Only in the NR1608 realized a DTS:X surround technology.