Onkyo TX-NR708 Home Theater Receiver - Product Review

Introduction to the Onkyo TX-NR708

Onkyo TX-NR708 3D Compatible Network Home Theater Receiver - Front View with Accessories
Onkyo TX-NR708 3D Compatible Network Home Theater Receiver - Front View with Accessories. Photo (c) Robert Silva Licensed to About.com

The Onkyo TX-NR708 Home Theater Receiver has up-to-date features and an abundance of connectivity options. The NR-TX708 is rated to deliver 110wpc, and features TrueHD/DTS-HD Master Audio decoding and Dolby Pro Logic IIz processing. On the video side, the TX-NR708 has 7 3D-compatible HDMI inputs with analog to HDMI video conversion and 1080p upscaling. Extra bonuses include iPod/iPhone connectivity, Internet Radio, and two subwoofer outputs. To find out more, keep reading this review.

For an additional look and perspective, also check out my Photo Gallery and Video Performance Tests.

Product Overview

The features of the TX-NR708 include:

1. The TX-NR708 is a THX Select2 Plus Certified 7.2 channel home theater receiver (7 channels plus 2 subwoofer outs) delivering 110 Watts into each of 7 channels at .08% THD.

3. Additional Audio Processing: THX Listening Modes, Dolby Pro Logic IIz, Audyssey DSX, Dyanamic EQ, Dynamic Volume, Music Optimizer.

4. Audio Inputs (Analog): 7 Stereo Analog, 1 dedicated stereo Phono input, 1 set of 7.1 Channel Analog Audio inputs.

5. Audio Inputs (Digital - Excluding HDMI): 2 Digital Optical, 3 Digital Coaxial.

6. Audio Outputs (Excluding HDMI): 1 Set - Analog Stereo, One set - Zone 2 Analog Stereo Pre-outs, 1 Set - 7 Channel Analog Pre-outs, and 2 Subwoofer Pre-outs.

7. Speaker connection options for Bi-amp, Surround Back, and Powered Zone 2 speaker provided. Certified for 4-ohm operation.

8. Video Inputs: 7 HDMI ver 1.4a (3D pass through/Audio Return Channel capable), 2 Component, 5 Composite and 4 S-Video. One set of AV inputs mounted on front panel.

9. Video Outputs: 1 HDMI, 1 Component Video, 2 Composite Video, 2 S-Video.

10. Analog to HDMI video conversion (480i to 480p) and upscaling from 480p to 1080p via HDMI using Faroudja DCDi Cinema processing. HDMI pass-through of native 1080p and 3D signals.

12. 40 Preset AM/FM/HD Radio-Ready (accessory module required) Tuner, Sirius Satellite Radio via Optional Tuner/Antenna.


13. Network Connection via Ethernet: Internet Radio access - (Pandora, Rhapsody, Sirius Internet Radio, vTuner, Napster, Mediafly, and Slacker).

14. DLNA Certified for access to digital media stored on PCs, Media Servers, and compatible network-connected devices.

15. Windows 7 Compatible.

16. USB port for accessing flash drive stored audio files.

17. iPod/iPhone connectivity/control via USB (audio only with USB) or optional docking station (audio, video, photo access). Rear mounted docking port connection.

For an additional up-close, physical, look at the features and connections of the TX-NR708, check out my Photo Gallery.


Zone 2 Option

The TX-NR708 allows for connection and operation of a 2nd Zone. This allows a second source signal to speakers or a separate audio system in another location. This is not the same as just connecting additional speakers and placing them in another room.

The Zone 2 function allows control of either the same or separate, source than the one being listened to in the main room, in another location. For example, the user can be watching a Blu-ray Disc or DVD movie with surround sound in the main room, while someone else can listen to a CD Player in another room, at the same time. Both the Blu-ray Disc or DVD player and CD player are connected to the same receiver but are accessed and controlled separately using the same main Receiver.


3D Compatibility

The Onkyo TX-NR708 is 3D Compatible. This receiver will HDMI will detect 3D source signals automatically and pass them through to a 3D-enabled TV without further processing.


Audio Return Channel

What this function allows if the TV is also HDMI 1.4-enabled. is that you can transfer audio from the TV back to the TX-NR708 and listen to your TV's audio through your home theater audio system instead of the TV's speakers without having to connect a second cable between the TV and home theater system.

For example, if you receive your TV signals over the air, the audio from those signals goes directly to your TV. Ordinarily, to get the audio from those signals to your Home Theater receiver, you would have to connect an extra cable from the TV to the home theater receiver for this purpose. However, with audio return channel, you can simply take advantage of the cable you already have connected ​between the TV and the home theater receiver to transfer audio in both directions.


Hardware Used

Home Theater Receivers: Onkyo TX-SR705, Harman Kardon AVR147.

3D Blu-ray Disc Player: Samsung BD-C7900

Loudspeaker/Subwoofer System 1 (7.1 channels): 2 Klipsch F-2's, 2 Klipsch B-3s, Klipsch C-2 Center , 2 Polk R300s, Klipsch Synergy Sub10.


DVDO EDGE Video Scaler used for baseline video upscaling comparisons.

High-Speed HDMI Cables provided by Atlona for this review. 16 Gauge Speaker Wire used.

Level checks made using a Radio Shack Sound Level Meter


Software Used

The software used in this review included the following titles:

3D Blu-ray Discs: Cloudy With a Chance of Meatballs, Disney's A Christmas Carol, Goldberg Variations Acoustica, Monster House, My Bloody Valentine, Space Station, and Under The Sea.

2D Blu-ray Discs: Across The Universe, Avatar, Hairspray, Iron Man 1&2, Kick Ass, Percy Jackson and The Olympians: The Lightning Thief, Shakira - Oral Fixation Tour, Sherlock Holmes, The Expendables, The Dark Knight, Tropic Thunder, and Transporter 3

Standard DVDs used included scenes from the following: The Cave, House of the Flying Daggers, Kill Bill - Vol 1/2, Kingdom of Heaven (Director's Cut), Lord of Rings Trilogy, Master and Commander, Outlander, U571, and V For Vendetta.

CDs: Al Stewart - Sparks of Ancient Light, Beatles - LOVE, Blue Man Group - The Complex, Joshua Bell - Bernstein - West Side Story Suite, Eric Kunzel - 1812 Overture, HEART - Dreamboat Annie, Lisa Loeb - Firecracker, Nora Jones - Come Away With Me, Sade - Soldier of Love.

DVD-Audio discs included: Queen - Night At The Opera/The Game, Eagles - Hotel California, and Medeski, Martin, and Wood - Uninvisible, Sheila Nicholls - Wake.

SACD discs used included: Pink Floyd - Dark Side Of The Moon, Steely Dan - Gaucho, The Who - Tommy.

Audio Performance

The TX-NR708 delivers great sound from analog and digital sources. Power output is sustained over long listening sessions.

I compared direct 5.1 analog audio, HDMI, and Digital Optical/Coaxial audio connection options. I fed uncompressed two and multi-channel PCM signals, as well as undecoded bitstream signals via HDMI and Digital Optical/Coaxial from an OPPO BDP-83 Blu-ray Disc player to compare externally decoded audio and the internal audio decoding of the TX-NR708.

The TX-NR708 can also operate a 2nd Zone. I was able to run 5.1 channels in the main room and two channels in a second room, and using the provided second zone control options. However, only analog audio sources can be sent to Zone 2.

I was able to access DVD/Blu-ray audio in a 5.1 channel setup and also access FM radio/Intenet Radio/CDs via two channel setup in another room using the TX-NR708 as the control for both rooms. Also, I could run the same music source in both rooms simultaneously, one using 5.1 channels and the second using 2 channels. The TX-NR708 can run a 2nd zone via its own amps (using provided speaker connections) or using a separate external amp via Zone 2 preamp output.

I also set up the Pro Logic IIz front height and Audyssey DSX wide surround options. Pro Logic IIz did provide a somewhat fuller soundfield in front and above, filling gaps in the soundfield in between and above the front left, center, and right speakers moving towards the listening position. Likewise, Audyssey DSX provided a fuller soundfield on the sides, between the surround and front speakers.


However, neither the extra height or wide channels provided a dramatic improvement that would necessarily justify added expense and placement of additional speakers to take advantage of the effects. The main issue is that although the Dolby Pro Logic IIz and Audyssey DSX give consumers added flexibility in speaker setup, there is no content specifically mixed to take maximum advantage of extra height or wide channels. This means that the TX-NR708 has to produce the height or wide surround effects from within the current Dolby/DTS decodable surround sound framework.

Sounds that can take advantage of Dolby Pro Logic IIz and/or Audyssey DSX (depending on how the sound was actually mixed) include rain, thunder, lighting, plane and helicopter flyovers, gun fights, action with exaggerated horizontal or vertical movement.

My suggestion: If you purchase the TX-NR708, or similar home theater receiver, equipped with Dolby Pro Logic IIz and/or Audyssey DSX, use the opportunity to experiment to see if either height or wide surround speakers would be of benefit in your listening environment.

NOTE: I did not use the TX-NR708's 2nd subwoofer option in this review.


Video Performance

The TX-NR708 passed 1080p, 1080i, and 720p high definition video signals from Blu-ray Disc sources without introducing additional artifacts. Also, using the HQV Benchmark DVD, I found that the internal scaler of the TX-NR708 does a very good job minimizing jaggie artifacts when upscaling analog video to 1080p and a surprisingly good job with video noise reduction, but did display some softness in detail.

In addition, testing also revealed that the TX-NR708 did not do well in eliminating moire patterns and displayed some instability in frame cadence detection.

For a closer look at the video performance of the Onkyo TX-NR708, check out my Video Performance Test Gallery.

In addition, 3D Pass-Through did not appear to introduce any added artifacts associated with 3D performance, such as crosstalk (ghosting) or jitter that wasn't already present in the source material, or in the video display/glasses interaction process. In one set-up the 3D signal was passed directly from a Samsung 3D Blu-ray Disc player to a Toshiba 3D TV without going through the TX-NR708, while in a second setup the 3D signal was passed from the Blu-ray Disc player through the TX-NR708 before going to the 3D TV.

The TX-NR708 has more than enough video connections, including an abundance of 3D-enabled HDMI inputs and even a PC monitor input. S-Video connections are also included which are being eliminated in many new receivers.


What I Liked

1. Sound quality excellent in both stereo/surround modes. I have no complaints about the audio quality of the TX-NR708.

2. Lots of HDMI inputs, including one mounted on front panel.

3. Good video upscaling.

4. Incorporation of Network Connectivity with access to Internet Radio.

5. Multi-zone operation included. 2nd Zone operation is available via pre-outs (additional amplifier required) or by using 5.1 operation in the main room and using the 6th and 7th channel amplifiers to power a 2nd zone.


6. 3D and Audio Return Channel compatible.

7. Good onscreen user interface.

8. Excellent Speaker connection layout.


What I Didn't Like

1. Remote difficult to use in darkened room - only Remote Mode/Input Select buttons are backlit.

2. Only one connection provided for both iPod and HD Radio docking stations.

3. Not designed for larger rooms - refer to THX Select2 Plus Certification.

4. No Built-in WiFi.


Final Take

The TX-NR708 delivers great sound. Practical features I liked included: Comprehensive surround sound processing, analog-to-HDMI video conversion and upscaling, abundant HDMI connections, dedicated phono input, iPod connectivity, and 3D pass-through.

Additional features I liked were the inclusion of built-in PC networking, internet radio access (including Pandora, Rhapsody, Sirius Internet Radio, vTuner, Napster, Mediafly, and Slacker), and both speaker connections or preamp outputs (your choice) provided for 2nd zone operation.

The TX-NR708 performs well in both stereo and surround modes, and with both analog and digital audio sources. There was no sign of amplifier or listening fatigue.

I also found the analog to HDMI video conversion and upscaling functions to be very good for a home theater receiver although some improvement would be desirable in maximizing detail enhancement and frame cadence detection.

The TX-NR708 packs in a lot of setup and connection options, making the user manual a must read before using. The TX-NR708 is definitely worth consideration.

Disclosure: Review samples were provided by the manufacturer. For more information, please see our Ethics Policy.