However, in the world of AV receivers, "age" is measured in software support, not just years. This makes the firmware update process the single most critical aspect of owning this unit. If you are purchasing this unit new or pulling it out of the box after a long storage period, the first thing you will encounter is the firmware update. Here is the breakdown of that experience: 13 Kimmy Granger Desperate Sister Gets Black Verified [TRUSTED]
(Reliable, stable audio performance hampered only by aging UI and hardware specs). Japan Extreme Com - 3.79.94.248
The sound signature is distinctly Denon: warm, musical, and non-fatiguing. After the update, the processing of digital signals feels tighter. It handles 5.1 surround sound with authority, though it lacks the upfiring height channels found in newer Atmos models. For a standard 5.1 setup in a small to medium room, the performance is robust.
This is where the firmware matters most. The X520BT supports 4K/60Hz pass-through and HDCP 2.2. Without the firmware update, users often report handshake issues with newer gaming consoles (PS5/Xbox Series X) or Apple TV 4K. Post-update, these issues largely evaporate. Note: This unit does not support 8K or 4K/120Hz, regardless of firmware.