Friday, December 5, 2008

Onkyo 706 vs. 806 vs. 876 vs. 906 vs. 886P

The Onkyo 2008 lineup has 4 THX certified AVR's and one THX certified processor/preamp. All five Onkyo products have 7.1 analog pre-amp outputs so they can be used with separate external amplifiers. They also all support the internal decoding and the external bit-streaming of the newest Dolby TrueHD and DTS-HD MA codecs used by the Blu-ray format. Below is a list of the base features that they all have in common.

base features
  • THX certified
  • 7.1 analog inputs
  • 7.1 analog pre-amplifier outputs
  • 3 coax and 3 optical SPDIF digital inputs
  • 1080p upscaling, Deep Color (36bit), xvYCC color support
  • Dolby Digital Plus, Dolby TrueHD and DTS-HD Master Audio decoding
  • Sirius and XM satellite radio
  • available in black or silver
As you step up through the Onkyo product line higher end features are incrementally added. Other than power, dimensions, and price; the major changes are highlighted below.

TX-SR706
  • THX Select 2 Plus
  • Audyssey MultEQ
  • HDMI v1.3a 4in, 1out
  • two TI 32-Bit DSP chips
  • Faroudja DCDi Cinema video processing chip
  • 192 kHz/24-Bit Cirrus Logic DACs
  • 100W x 7 ch
  • exposed front controls (no flip down panel)
  • 14.8" x 17.1" x 6.9"
  • 27 pounds
  • 5.9A power consumption
  • MSRP $800, street $500

TX-SR806
  • THX Ultra 2 Plus
  • Audyssey MultEQ
  • HDMI v1.3a 5in, 1out
  • two TI 32-Bit DSP chips
  • Faroudja DCDi Cinema video processing chip
  • 192 kHz/24-Bit Cirrus Logic DACs
  • 130W x 7 ch
  • 16.9" x 17.1" x 7.6"
  • 37.5 pounds
  • 7.8A power consumption (idle: 88W for 6ohm and 56W for 4ohm settings)
  • MSRP $1000, street $600

TX-SR876
  • THX Ultra 2 Plus
  • Neural THX
  • Audyssey MultEQ XT
  • ISF (Imaging Science Foundation) video calibration
  • HDMI v1.3a 4in, 2out
  • HD radio
  • three TI (Aureus) 32-Bit DSP chips
  • HQV Reon-VX video processing chip
  • 192 kHz/24-Bit Burr-Brown DACs (PCM1796)
  • 140W x 7 ch
  • switched 110V trigger outlet
  • 18.1" x 17.1" x 7.6"
  • 53.1 pounds
  • 9.5A power consumption
  • MSRP $1600, street $1000

TX-SR906
  • THX Ultra 2 Plus
  • Neural THX
  • Audyssey MultEQ XT
  • ISF (Imaging Science Foundation) video calibration
  • HDMI v1.3a 4in, 2out
  • HD radio
  • DLNA audio streaming; Ethernet and USB (AAC, WMA, MP3, WAV, OGG, and FLAC)
  • three TI (Aureus) 32-Bit DSP chips
  • HQV Reon-VX video processing chip
  • 192 kHz/24-Bit Burr-Brown DACs (PCM1796)
  • 145W x 7 ch
  • switched 110V trigger outlet
  • 18.1" x 17.1" x 7.6"
  • 54 pounds
  • 9.8A power consumption (standby 20W, idle 140W)
  • MSRP $2000, street $1500

PR-SC886P (pre-amp/processor)
  • identical features of the TX-SR876
  • except 7.1 XLR pre-amp outputs replace the internal power amplifier
  • Ethernet for remote control
  • 17.5" x 17.1" x 7.6"
  • 29.3 pounds
  • 1.1A power consumption
  • MSRP $2050, street $1600
Amplifier power output is what signifies the difference between the THX Select and THX Ultra classes. A 30W - 45W increase only amounts to an additional 1 or 2 dB of headroom which isn't all that significant.

The TX-SR706 and the TX-SR806 both use the same Faroudja video chip which has a "blue dots" problem with 1080p sources that can be fixed by disabling the on screen display (OSD). The Faroudja video chip also has a black clipping problem which is active even when HDMI pass-through mode is enabled. Clipping the black level doesn't let "blacker than black" signals pass through, such as a pluge test pattern, which makes it difficult to properly calibrate the brightness on your video display. So even when in video pass-through mode the Faroudja chip is modifying the video signal. On the the audio side, the analog 7.1 inputs lack ADC's so all digital processing is bypassed, this means that the digital delay, equalization, surround processing, and bass management features are not operational. Channel level control with the 7.1 inputs does work since the gain adjustment is done in the analog domain.

The upgrade from the TX-SR706 to the TX-SR806 adds one HDMI input and a cosmetic flip down panel that hides a number of infrequently used controls and input jacks. Is the extra power and improved looks of the flip down panel worth an exta $100?

The upgrade from the TX-SR806 to the TX-SR876 removes an HDMI input but replaces the Cirrus Logic DACs with Burr-Brown DACs and replaces the Faroudja video processor with one by Reon. The Reon upgrade allows ISF video calibration which is convenient but not that useful if you prefer to do your de-interlacing and video scaling on your flat panel display. Some displays, such as the Pioneer Kuro 9G plasmas, provide higher quality video processing circuitry. In fact, 24 FPS PureCinema film mode doesn't operate with a 1080p source, so Reon processing could even be detrimental in this particular case. Another interesting addition is that the TX-SR876 has an extra TI DSP chip, its use is speculated to be for the extra processing capability needed by the Audyssey MultEQ XT, Dynamic Volume, and Neural THX features. While all these features are nice, except for the potential Reon 1080p Kuro PureCinema problem, the main improvement are the Burr-Brown DACs. It is interesting that last years TX-SR805 had the Burr-Brown DACs. The important question is the improved signal quality of the Burr-Brown DACs worth an extra $400?

The upgrade from the TX-SR876 to the TX-SR906 adds DLNA audio streaming over Ethernet or from the USB port. Audio streaming your music collection is a great feature if you have a home network set up but is it worth an extra $500? Or is the modular addition of a streaming Apple TV, Sony PS3, or a Roku box a better value?

The upgrade from the TX-SR876 to the PR-SC886P (pre-amp/processor) is more of a horizontal move than an upgrade. Since it is a pre-amplifer, the internal power amplifiers have been replaced by 8 balanced XLR outputs. The PR-SC886P has an Ethernet port but it lacks the USB port and DLNA capability the TX-SR906 has. The PR-SC886P is made by the Onkyo Pro division which makes it more difficult to find and since it isn't a high volume product it doesn't get the same pressures on price that the mainstream Onkyo products have. While $1600 is a great price for comparable high-end pre-amps, it does seem odd for the removal of features (power amps) to cost an extra $100.

Unless the performance of the Burr-Brown DACs is a significant improvement, the best value is to use a TX-SR706 or a TX-SR806 as a pre-amp/processor. This represents a $1000 - $1200 savings. That way, in a couple years when the newest greatest codec, DSP algorithm, or technological HT feature comes out it will be that much easier and less painful to upgrade.

For the latest prices and availability check out the Onkyo THX processors store.


2 comments:

Jianwu said...

Great article. Now if only the sound quality is considered, are there any big differences between them? I really don't care about the video thing that much. Just want to get a receiver with really good sound quality. I read some reviews saying that with 876 they can hear something they couldn't hear before with other receivers. Will 806 produce the same sound as 876? I am also considering 875 since its price is really attracive. But the issue that it runs really hot concerns me. Should that be a true concern? Thanks.

Erik said...

The 876 and the 906 use the Burr-Brown DACs (digital to analog converters) while the lower performance 706 and 806 models use Cirrus DACs. I don't know how much of an audible improvement the Burr-Brown DACs will make but they are widely respected for their high quality.

I wouldn't be too concerned about the 876 having a heat issue. It does run warm but it shouldn't be a problem if you give it good airflow. Check out my Onkyo 876 power consumption report for more info.