Onkyo TX-NR509 has 5 channel amplifier and delivers 80 W (8 Ω, 20 Hz - 20 kHz, 2 channel driven).
The Receiver has 1080p passthrough.
Advanced Music Optimizer
Compressed music enhancement in Onkyo TX-NR509 is done by Onkyo’s Advanced Music Optimizer. While MP3 or AAC files may sound fine through the headphones of your portable digital player, the limitations of these files can be exposed when played back through a quality home entertainment system. This is because a significant amount of high-frequency bit information is lost during the file-compression process. To counter this, Onkyo has designed the Advanced Music Optimizer to compensate for lost bit information and improve the quality of compressed audio signals. This results in a clearer and more expansive sound. Also included in this technology is a loudness correction feature that further improves the audio character of compressed files.
Onkyo TX-NR509 comes with Audyssey Dynamic EQ and Audyssey Dynamic Volume.
Audyssey Dynamic EQ selects the best possible frequency response and surround volume levels moment-by-moment. This ensures that the bass response, tonal balance and surround impression remain constant despite changes in volume. This is the first technology that carefully combines information from incoming source levels with actual output sound levels in the room, a pre-requisite for delivering a dynamic volume solution.
Your Listening experience can be greatly diminished when there are significant shifts in volume between television programs, commercials and within the program material itself. When this happens you must constantly adjust the volume to maintain your desired listening level. Audyssey Dynamic Volume monitors the volume of program material moment-by-moment and automatically adjusts it, maintaining the desired listening level for all content while optimizing the dynamic range to preserve impact.
Onkyo TX-NR509 comes with[y] Audyssey 2EQ room correction system and includes the calibration microphone.
Audyssey is an acoustic measurement technology which automatically restores the acoustic distortion caused by the acoustic behaviour of a room with only a push on a button. Audyssey equalization provides an clear, accurate, natural sound with voices and dialog that become focused and intelligible, restoring the musical balance. Musical instruments and sound effects become precisely localized and the surround soundstage is made seamless and enveloping.
Onkyo TX-NR509 can be connected to internet using ethernet cable or wirelessly[y] via Front USB (optional UWF-1 sold separately). It has 4 HDMI inputs. There are 2.1 (Surround Back and Sub) channel analog pre-outs for external amplification.
Front panel has USB, Composite Video and RCA Audio inputs.