It’s strongly recommended to compare different receivers if you want to choose the best one: Onkyo TX-NR555 vs Onkyo TX-NR676.
AV receivers under review have the same number of channels. In terms of power, there are differences, the TX-NR555 has such a ratio W/Ohm - 130/6, while the TX-NR676 has a power of 165/6. A common feature for devices is the same total harmonic distortion - 0.08%.
The manufacturer installed different DACs, the TX-NR555 received the model Hi-Grade 384 KHz/32-bit, but the TX-NR676 is equipped with AK4458 384 KHz/32-bit. Each of the compared opponents supports Bi-amping. Both Onkyo TX-NR555 and Onkyo TX-NR676 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. Both devices can work with such Apple Music services: AirPlay. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Onkyo TX-NR555 works with Deezer, TIDAL, Pandora, but the Onkyo TX-NR676 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 TX-NR555 and the TX-NR676. None of the devices can increase the resolution of the incoming video signal. Operation with the Dolby Vision is only possible with the TX-NR676.
The number of HDMI inputs/outputs varies depending on the receiver, the TX-NR555 has 6/1, and the TX-NR676 has 7/2. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the TX-NR555 and the TX-NR676. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. TX-NR555 and TX-NR676 support the standard HDCP 2.2. Like most receivers, our models have a built-in phono stage for connecting a vinyl player.
Ability to create 2 Multi zones inherent in both AV receivers. Voice control of the basic functions of the receiver is not realized in both models. There is an ECO mode in either AV receiver. The Onkyo TX-NR676 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available both models. A DTS:X surround technology is supported by devices from our comparison.