Amplifier
| Onkyo TX-NR809 |
Onkyo TX-NR818 |
7 channel Amplifier: Onkyo TX-NR809 features 7 channel power amplifier. It is rated at 135 W (8 Ω, 20 Hz - 20 kHz, 2 channel driven) and is able to drive 4 ohm speakers. |
7 channel Amplifier: Onkyo TX-NR818 features 7 channel power amplifier. It is rated at 135 W (8 Ω, 20 Hz - 20 kHz, 2 channel driven) and is able to drive 4 ohm speakers. |
- WRAT (Wide Range Amp Technology): Onkyo TX-NR809 and Onkyo TX-NR818 feature Onkyo’s Wide Range Amp Technology (WRAT) circuit layout that prevents phase shifting by pushing the roll-off point higher than the listening-level frequency. Amplifying sound without phase shift creates an uncommonly well-focused and realistic audio image. If phase shift occurs and signal timing is not accurate, then neither is the resulting audio image.
- 3-Stage Inverted Darlington Circuitry: Onkyo TX-NR809 and Onkyo TX-NR818 feature 3-Stage Inverted Darlington Circuitry. Standard amplifiers employ a negative feedback (NFB) design that counters distortion by feeding back the opposite phase of the output signal into the input stage. Unfortunately, NFB is easily affected by inverse electromotive forces from the speakers, leading to an increase in circuit noise. Three-Stage Inverted Darlington Circuitry is a core Onkyo technology incorporating a low-NFB design that makes the sound more natural. Sensitive to oscillations, this circuitry requires very advanced control technology in order to be incorporated into the amplifier.
thxtradecertification Select™2 Plus certification
Onkyo TX-NR809 and Onkyo TX-NR818 are thxtradecertification Select™2 Plus certified. This means that they are ideally suited for a room where the screen-to-seat viewing distance is approximately 3 to 4 meters, and the room size is approximately 56 cubic meters.
- THX™ Certification: THX™ Certification offers optimal performance, superior quality and seamless integration. THX works with partners from the ground up, so that certified products deliver professional quality audio-visual experiences right out of the box. They only certify the very best products with uncompromised quality, performance and consistency. They ensure that THX certified devices play well with lower performing devices and components. THX listening modes make the receiver to have one speaker set up for movies, music and games. They are tested for power output, bass management, signal-to-noise ratio and feature THX Loudness Plus, Boundary Gain Compensation, Timbre Matching and RE-EQ.
- Power Output: Power output is tested to ensure the receiver accurately plays source material at THX Reference Level in every input and mode and at every sampling rate for all possible playback combinations selected by the listener.
- Frequency Response: THX has strict requirements for frequency response to ensure that you hear all the details in high-resolution tracks, ensures dialog in movies, and vocals in music are clear while maintaining deep, impactful bass output that doesn’t overpower the listening experience.
- Signal-to-Noise Ratio: THX tests the signal-to-noise ratio to ensure the unit is designed to have low noise performance with very little to no audible hiss from the speakers.
- Bass Management: THX requires an 80Hz crossover point in the setup menu to ensure proper bass management in every THX Certified AVR. This setting confirms that the subwoofer handles low frequencies, freeing up the loudspeakers to handle mids and highs.
- THX Loudness Plus™: THX Loudness Plus™ is a volume control technology featured in THX Certified Dominus, THX Certified Ultra and THX Certified Select AV Receivers, and preamplifiers that automatically adjusts the front-to-back speaker level relationship as you turn the volume down. With THX Loudness Plus, home theater audiences can now experience the rich details of surround sound at any volume level.
- Boundary Gain Compensation: Sitting near a wall may result in increased acoustic levels at the lower frequencies. BGC corrects the way low frequency sound is perceived when seated near a wall. This results in a more accurate bass response.
- Timbre Matching: Your ears hear different tonal qualities in sounds coming from different directions. Timbre Matching restores the frequency balance between your front and surround speakers ensuring seamless and smooth panning between the front to back of the room.
- RE-EQ: Many movie soundtracks are mixed in studios for playback in large cinema auditoriums with an array of speakers. When played on home systems, they may appear abrasive and edgy. Re-EQ establishes a more accurate tonal balance when enjoying movies in your home.
Speaker Configurations
Onkyo TX-NR809's and Onkyo TX-NR818's amplifiers can be assigned for different speaker configurations.
- Configurations: Available configurations are:
- Onkyo TX-NR809: 5.2, 7.2 with internal amplifier.
- Onkyo TX-NR818: 5.2, 7.2 with internal amplifier and 9.2 with addition of external 2 channel amplifier.
- Front Wide Channel support: With the presence of two front wide speakers you can enhance the front surround stage. The following speaker configurations are available for front wide channels:
- Onkyo TX-NR809: 7.2.
- Onkyo TX-NR818: 9.2.
- 2-ch Bi-Amp: Both models are able to bi-amp up to 2 main channels simultaneously. During bi-amplification two amplifiers are used for one speaker. One amplifier powers the midrange and tweeter section of the speaker and another amplifier powers the low frequency woofers. Each amplifier is less loaded and performs better. In order to use this feature speakers must have 2 pairs of connectors.
Audyssey DSX
Onkyo TX-NR809 and Onkyo TX-NR818 support Audyssey DSX which allows you to augment a standard five-channel home theater with either two Front Wide or two Front High speakers. The Wide channels create an expansive soundstage and bring out convincing directional effects. Alternatively, Height channels can add a vertical dimension to movie and game soundtracks.
Sound Processing
- Audyssey: Both receivers come with Audyssey Dynamic EQ and Dynamic Volume.
- 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.
- Dynamic Volume: 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.
- Compressed Music Enhancer: Onkyo TX-NR809 and Onkyo TX-NR818 feature Compressed Music Enhancer which enhances the quality of the music files with lossy compression.
- Advanced Music Optimizer: Compressed music enhancement in Onkyo TX-NR809 and Onkyo TX-NR818 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.
Room Calibration
Onkyo TX-NR809 comes with Audyssey MultEQ XT and Onkyo TX-NR818 comes with Audyssey MultEQ XT32 room correction system.
- Audyssey Room Calibration: 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.
