Onkyo TX-SR806 THX Ultra2 Plus 7.1 A/V Receiver

Onkyo TX-SR806 Receiver


I've been following and reporting to you on Onkyo's 800 series receivers for some time now.  They occupy that juicy $1000ish slice of the market and have done quite well, as such.

Milestones include the original 800 in 2004, a most impressive THX Select receiver, and last year, when they raised the price by only $100, yet achieved THX Ultra2 status on the model 805.

Today's subject is no less than the newest entry in that line, the TX-SR806.  In the broad strokes it ups the ante with better video processing, a revised I/O compliment which tilts things more towards the digital, and THX Ultra2 Plus status, which we will take the opportunity to introduce to you later in this review.

All without raising the SLP from $1099.  Did they have to give up anything?  Let's find out!


  • Codecs: Dolby Pro Logic IIx, Dolby Digital+, Dolby TrueHD, DTS (ES, Neo:6, 96/24), DTS-HD Master
  • Precision: 24-Bit/96kHz A/D, 24-Bit/192kHz D/A
  • 2-Zone Operation
  • Satellite Radio Capable
  • Power Output: 130 watts RMS/Channel @ 0.03%THD, 2 Channels Driven into 8 Ohms
  • MFR: 10Hz - 100kHz (+1dB, -3dB)
  • THD:  0.08% (20Hz - 20kHz)
  • Dimensions:  7.6" H x 17.1" W x 18.1" D
  • Weight: 45.2 Pounds
  • MSRP: $1,099 USA
  • Onkyo USA

The Design of the Onkyo 806

Small things don't go unnoticed. When FedEx dropped the unit off at my office, I immediately noticed that I could lift the thing without too much strain whereas last year I distinctly remember asking for help getting the previous model into the car.  What's more amusing is that the very next day I was contacted by a reader asking if I would be reviewing the 806, and what did I make of the weight reduction.  Consumers notice things like that.

As I've come to expect, the TX-SR806 arrived very well packed. Two substantial pieces of Styrofoam cradle the unit, and a soft foam sheet inside the requisite plastic bag protects it from scuffs when being unpacked.

The front panel is the now familiar Onkyo layout.  Direct input selection is available, and the large machined aluminum volume knob has a nice solid feel.  Behind the drop down panel are a plethora of mainly "one-use" buttons such as the setup cursor pad, but also mode selection buttons, should the occasion arise where they are more convenient than reaching for the remote.

Onkyo TX-SR806 Receiver

The back is where things start to change.  Though a dedicated phono/turntable input still survives in this digital age, beyond it and counting the convenience input on the front, there are a total of eight addressable inputs, five of which have composite and S-Video, and two have rec-out lines. Three coax, two optical, and 5 HDMI digital jacks, plus two component video lines, may be assigned to any of the core inputs.  Not to be forgotten is the 7.1 analogue input (again assignable to any of the core inputs), 7.1 preouts, AM and FM antenna jacks, and ports for both XM and Sirius satellite Radio. The 806 boasts 2-Zone opration with stereo outputs in both line level and speaker level.

For the custom installer a modicum of features: IR in/out, 12V trigger out, and an RS-232 communications port.

The biggest news with the 806 is that Onkyo has now upped the video processor from a basic implementation of the Sage/Faroudja FLI2300, to the 30336, making it effective all the way up to 1080 line.  We'll deal with its implementation and limitations a little later.

The multi-channel line-level jacks are comprehensively color coded, but the speaker jacks are themselves not color coded like last years model: the silk screening on the back panel has the common color code but that is all but invisible when one is hunched over from the front trying to make connections in a rack or cabinet.  While certainly of adequate strength, the speaker connectors won't take a spade lug, but they worked with my speaker wire termination of choice: the venerable banana.

Inside: more changes.  Popping off the lid we make some intuitive observations.

Onkyo TX-SR806 Receiver

One can see at a glance the large (though not overly so) power supply off to one side.  The chassis is then divided by one large full-width heat sink, beyond which all the boards are laid horizontally and thus "stacked".

Gone are what we thought to be intelligently implemented air conduits either side of the heat sink in the 805, each with an on demand fan.  Instead a single fan, mounted in free air mind you, sits front and center.  The point of it is questionable since, as anyone with experience designing cooling for electrical components will tell you, this is about the most inefficient way to add active cooling to a passive heat sink system.  The relative relevance of this will be of more importance when we discuss amplifier power later on in this review.

For the 806, Onkyo went with a Texas Instruments DSP package and Cirrus Logic 24bit/192kHz DACs on all channels.

The Onkyo 806 Software

Besides amplifier power, this is what an AVR comes down to.

The Video Prcocessor

As mentioned Onkyo has stepped up their game with regards to the video processor. Since this is the most significant upgrade, we'll deal with it first.

Onkyo TX-SR806 Receiver

In terms of deinterlacing, it is functional, but not stellar.  Putting it through the relevant portions of our DVD Player Benchmark tests, it nails all the essentials but has a hard time keeping up on more challenging material such as our mixed content tests and it completely falls apart on AVIA Pro motion tests (both 24 and 30 fps source).  Stepping up to 1080 line source material it had no problem finding and correctly processing a clean 3-2 cadence, and it does do motion adaptive deinterlacing of video based material. Scaling of 480 line to 1080 line is also adequate.

A byproduct of the new processor is that you get a much updated looking onscreen display even over HDMI at 1080p.  Gone are the block-type text of yesteryear in favor of a smoother more eye pleasing information display.

Basic video adjustments (black level, white level, etc) are available and are independent for each and every source. This is excellent, but these adjustments are tedious to use as the setup menu blocks your video, so you have to hit enter to "view picture" and wait several seconds to see what your are doing. Even more tedious is the aspect ratio control: Though not comprehensive it is adequate in its choices but there is only one setting shared by all inputs and it is buried deep in a setup menu.

The bottom line is that if you have nothing else, the 806's video processor is nice, especially for something like HD Cable or Satellite boxes which at best turn out their native 1080i60 signal format.  For hard core DVD aficionados there is no question an Oppo 983 player is still your best bet, yet not "passed through" the Onkyo.  Why?  The 806 is NOT capable of unaltered HDMI repeating!  At the very least it drops below black (even if the source is component analogue video).

Ultimately you are better running source straight to display, but that is going to be a problem for Blu-Ray since you MUST run it through the Onkyo in order for it to strip the HD audio from the HDMI stream.  This could very well be a deal breaker for many users and we hope that Onkyo can repair this flaw via firmware in the future (although without knowing the root cause we cannot say whether that is even a possibility).

Moving on to audio...

The 806 carries on Onkyo's status as a benchmark in volume control features.  The overall granularity of all adjustments, including master volume level, are half-dB increments.  Power/On volume (Fixed or Last) and Max Volume (independent for Main and Zone2), separate headphone volume, choice of mute (-dB or cut): it's all here.

The 806 boasts 2-Zone operation with both line level stereo output as well as amplified speaker outputs for zones 2.  Sadly its utility is severely diminished by the fact that while you can monitor any source independent of the main zone, only analogue inputs are valid. In years past when analogue was still dominant and DSP was still expensive, this was the norm.  But in this day and age of digital i/o prevalence, it seems a shame to omit the secondary decoder and pair of DACs required to get a fully functional Zone2. Further, Zone2 "steals" the output devices from the surround back/rear channels so when Zone2 is on, 7.1 playback is not available in the main zone.

Everything Dolby has on the table right now, right up to Dolby Digital+ and TrueHD, is supported by the 806, and the implementation is as complete as can be hoped for.  The Pro Logic IIx Music non-mandatory adjustments are available to the user, although they are buried deep in the setup and thus discourage experimentation.  EX flags are recognized, but Surr.Encode flag in two-channel Dolby Digital is ignored.  Dynamic Range Control (DRC) takes a couple button presses to get at it and there is no indication on the front panel that it is engaged.

Lock-on time of digital bitstreams is good, and over HDMI it is much improved from the 805, but there are loud relays which seem to constantly engage/disengage as bitstreams start, stop, or change.  Depending on your disposition, it can get annoying.

At the start of a bitstream, the display will (briefly) show the difference in Dialnorm assertion with reference to the default -27. So for example, if you see "Dialnorm: +4 dB", that means the output of the decoder has been raised by 4 dB.

Everything DTS has on the table right now is also supported by the 806, right up to HD Master.  Traditional DTS is attenuated by 4 dB inside the processor per THX's requirements, equating it with Dolby Digital material encoded with the default Dialnorm value of -27 (for more information on Dialogue Normalization, please see our article Dialogue Normalization: Friend or Foe).  There is no dynamic range control facility for DTS though.

You can select for each input a default playback mode for each of the various possible input formats. So for example, for a given input, you can have it default to "Stereo" on Analog/2 channel PCM material, "THX" on Dolby Digital 5.1, and "Pro Logic II" on 2 channel Dolby Digital.  You can also set each format to simply use the last mode used and that is likely where most people will leave it.

Each input can be delayed ("lip-synch" delay) up to 250 ms in 5 ms increments.  This is excellent.

When configured for a 7.1 speaker array, you unfortunately cannot choose to send the surround channels of a 5.1 source to the back surrounds (or both sides and back surrounds).

We confirmed that the 806 responsibly down-mixes 5.1 soundtracks to stereo for the sake of headphones, or, heaven forbid, if you find yourself with only two speakers, for some reason.  But, as mentioned before, this does NOT work for Zone2 as Zone2 can only monitor stereo analogue sources to begin with.

Mono soundtracks are adequately handled by the 806, giving the user control of both which channels to matrix in (left, right, or both) as well as the output configuration (left/right, or center).  Academy Filter, one of those virtual no-cost things, is conspicuously missing.

Regrettably there is no option to digitize the 5.1 analog input and thus it cannot inherit the receiver's bass management and time alignment.  Even though the source may provide for these adequately, it will never benefit from the Audyssey system or THX processes, including the new THX Loudness Plus.  Speaking of which...


The 806 is our first look at an Ultra2 Plus unit, the main new feature of which is THX Loudness Plus.  This is a persistent setup choice and after experimenting with it I'm prepared to endorse its full time use.  The concept itself is not entirely new.  Soundtracks are crafted at industry standard Reference Level volume, a very loud level virtually never used in home theater settings.  In layman's terms, as we get into lower playback volumes the spectral response of our hearing changes, unequally so, as a function of direction.  As the volume drops we perceptually hear less extreme bass and treble in general, more so for sound sources behind us.  The net result is sound without the thrill of deep bass and surround sound which seems like it's just not there.  THX Loudness Plus is THX's take on an existing concept of correcting for this, bringing to the table their profound experience with soundtracks, including how we perceive them.  It applies their correction as a function of playback level: simply stated, the lower the volume, the more processing in terms of both spectral reshaping and relative channel level skewing to the surrounds.  The actual benefit: you hear a MUCH better low-volume facsimile of the full-volume multichannel soundtrack.

A legacy note: THX's Re-Eq can be turned off independently of the THX Cinema/THX Surround EX mode and to do so takes a few button presses.  We still would like to pressure both manufacturers and THX to allow this to be a persistent choice.  Right now, it's mandated that it reset to "On" whenever input or power is cycled.  In our article Cinema Sound and EQ Curves, we explain why the use of THX's Re-Eq depends, not on the media, but on the room's acoustics (meaning that using it or not should be a "Setup" choice).


The front panel display is dimmable. At the press of a button you can cycle through three brightness levels, but I must repeatedly make appeal: the lowest setting still is not low enough!

The front panel itself is still a frustrating mix of the useful and the useless. There are two lines of dot-matrix characters, plus a dedicated (though incredibly small) volume level indicator.  All status information, such as input format, post-process application etc., is carried by miniscule icons which, even at abnormally short distance, are all but indiscernible (and yes I have still have my 20-20 vision).  Their usefulness becomes a game of recognizing the position of the little blips (which is all they appear as, at any normal usage distance).

The Magic Wand

Onkyo TX-SR806 Remote Control

The remote is a bit of a departure for Onkyo.  Slightly smaller than previous offerings, it seems to give up something in terms of direct manipulation of functions.  For example, no more dedicated button for DRC or Re-Eq.  Buttons to select playback mode have been cut from 8 down to 4 (which means many more presses to get the mode you want).

The cursor pad area is decent with what is a fairy common layout.  Transport keys are varied in size, a little at least, which helps find the one you are looking for...a little.  "TV" gets its own dedicated power, volume, and channel buttons.  Muting is logically placed close to the main volume rocker which is nice.

On the whole a somewhat less than intuitive model which will requires some time and effort on the part of the user to train themselves before becoming at all adept with it.

Audyssey MultEQ / Bass Management

Onkyo has fully embraced the Audyssey automated setup and room compensation system as seen by its inclusion, in one flavor or another, in almost all their current models.

Enough has been said about MultEQ at this point, that we don't need to rehash the basics, except as it relates to its implementation in the 806.

As expected, it got speaker distance of the main channels perfect, except for the subwoofer which it interpreted as being 2.5 feet from me (instead of the actual 7.5 that it is).  It's not uncommon for such systems to turn out not-real values there, as a result of the way a room loads with bass, and in such cases it may well be best to leave it where Audyssey sets it (though the 805 hit my sub's distance bang on).  Also as expected, although relative level of one channel to another was perfect, master calibrating level was a couple dB off.  This is due to the necessarily inexpensive mic favoring spectral consistency at a cost of absolute level accuracy.

Disconcerting is Onkyo's continued omission of the choice for Audyssey's target curve.  Integral to the Audyssey MultEQ system is a choice of final curve it filters to:  the Audyssey curve, a Flat curve, or a Front curve.  The Flat curve, as its name implies, is a classic, "Let's make the system response as text-book neutral as we can," and is best for rooms which have already received a modicum of attention to their acoustics.  The Audyssey curve, which may be considered the default, is a shaped target which seeks to mitigate some of the inherent high frequency reverb of typical home spaces, not unlike what THX's Re-EQ's purpose is, but on a much more sophisticated level. The concept of the Front curve is to filter the front speakers as little as possible and make the rest of the system conform to them.  Yet integral as it is to the Audyssey system, Onkyo does not give you this choice of target curve.  Since it is inherent to the Audyssey system, "cost" is not an excuse for its omission.  Onkyo's answer to this is that while the 806 implements Audyssey with its default Audyssey curve, when in any THX Cinema mode, it implements the Flat curve.  This passes in my book because I tend to use THX processing most of the time in my acoustically treated room, but for those with good acoustics who eschew THX processing, you are out of luck here.

Switching gears to "Manual" (or if you simply override Audyssey's choices), crossover frequency can be set from 40 Hz to 100 Hz (10 Hz increments), and then 120 Hz, 150 Hz, and 200 Hz.

The crossover frequency can be set independently for each pair of speakers, the soundtrack's bass can be sent to both the main speakers and a subwoofer ("Double Bass" they call it), and the LFE channel can be low-passed at a different frequency from the rest of the bass being sent to the subwoofer . . . all of which we vehemently maintain are bad ideas, and we back that up in our essay on the subject: Miscellaneous Ramblings on Subwoofer Crossover Frequencies. It is no fault to the product's performance, but it questions Onkyo's marketing decision to give the people what they think they want even though it may mean they hang themselves with it (unaware as they may be).

In practice, this multiple crossover frequency thing is really not all that big of a deal, but if we are going to go through all this care to get the best D/A performance, the cleanest amplification, the tightest room acoustics, and then top it off with intelligent FIR based EQ, why undermine it all on a technicality?

Ultimately, I have no hesitation recommending the use of the Audyssey system to any 806 buyer, provided you, as THX recommends, do a double check of whatever is in your power to second guess, namely speaker settings, especially the subwoofer level.

The 806 has a new Audyssey feature:  Dynamic EQ.  This is, in every practical sense, the same idea as THX's Loudness Plus, but whereas this last is only "engageable" for THX playback modes, Dynamic EQ may be applied to everything else (though not the THX modes IF THX Loudness Plus is already enabled).   The goals of the two are one in the same, differing only in the underlying math.  Comparing the two is extremly difficult as one cannot "separate" THX Loudness PLus from the fundamental THX processes.  Anecdotally though, its not hard to identify Dymanic EQ as being the more "live" of the two.  It tends to add what I'd call "sparkle" to the sound, THX Loudness Plus being more "true" I feel.  If I had to pick a preference it would probably be THX's take, though if it were not available, I'd be just as happy with Dynamic EQ.  Moving forward I dont think I can live without at least one of them.

On the Bench

Here we found some, well, interesting numbers.

In terms of line level performance, within the audio band, the Onkyo exhibits a measured frequency response of 20 Hz - 20 kHz, + 0, - 1 dB. Inter-modulation distortion at the line level was actually below what our equipment can measure, while THD+N came in at a respectably low 0.00822%.

Next we confirmed Onkyo's published spec of 130W per channel, two channels driven.  We loaded two channels with 8 ohms (with the hardware set to the default >6ohm setting) and brought two channels up to 130W output where we measured THD+N at only 0.01944.  Simply excellent.

Next we moved on to the "cooking" tests.

As we've talked about in past reviews and articles, in all common amplifier topologies low-impedance loads have the inherent consequence of increased heat as the greater current (as opposed to voltage) is delivered.  Make no mistake: no matter how "good" a receiver is (no matter how much it costs), it cannot compete with separate power amplifiers for this reason.  There is simply too much crammed into one box.  Elaborate means of dissipating heat are possible, but they are expensive to the point of making the pursuit futile (i.e., you might as well just go the way of separates).

The 806 has what is common in any decent (and safe to use) receiver: a setting for low impedance speaker loads.  Specifically, in this case, you must set the receiver for either >6ohm loads or >4ohm loads.  Because of this we test the receiver's performance in both settings.

First we left the 806 in its 6 ohm setting, brought the output up to 1% THD (popularly accepted as the point of clipping), and measured the output with an 8ohm load.  We then loaded it with 4 ohms on each channel and measured again.  Switching the 806 to its  4 ohm setting we again measured with 8 and 4 ohm loads.  The results are tabulated as follows.

>6 ohm setting (default) >4 ohm setting
8 ohm load 144 Watts 36 Watts
4 ohm load 217 Watts* 56 Watts

* Time limited test under controlled laboratory conditions.

The results in the >6ohm setting are more than commendable for a receiver at this price point, with a special nod to the power delivered into 4ohms, demonstrating that the unit can swing some serious current, at least transiently.  The results when the unit was set of >4ohm load are disturbing to say the least, so much so that we must take a bit of a tangent to talk about exactly what that setting does and why it is there.

In a nutshell, it biases the power supply for less voltage and limits output as such.  The unit is prevented from dumping any significant amount of current, protecting it from ever going into a thermal meltdown, but consequently (in this case at least) putting the speakers at serious risk of damage from amplifier clipping.

The setting is there for safety reasons: when the governing bodies test an AVR for safety, included in what they do are amplifier tests involving steady state signals driven into test loads.  Under such conditions any amplifier gets hot, and when driving a low impedance load it gets even hotter.  In the case of just about every AVR on the market it gets too hot to be considered safe so the infamous speaker impedance setting is required: instead of getting hot, the amp's output is limited.  The consequences are that the unit is "safe", but underpowered in that setting (grossly so in the case of the 806).

Indeed one wonders how THX configured the unit during their tests as many THX speakers are 4ohm designs, yet in it's 4ohm setting the 806 is basically useless as an amplifier.

Now there have been some in the industry who will say, always "off the record" mind you, that using an AVR like the 806 in its default setting of >6ohms with speakers which are rated as 4ohm is just fine because no one actually plays steady state test signals all evening long.  They play movie soundtracks and music, neither of which taxes an amp the way steady state test signals do.  These people feel that the governing bodies' test methods are out of date and not indicative of real world usage.

On the flip side there are those who argue that what matters when it comes to safety is not what an AVR does "typically", but rather what is technically possible.  This seems a little extreme since it is technically possible for any automobile to be driven faster than is safe (by any standard) yet none are limited as such.

Safety is important and we at Secrets cannot endorse circumnavigating or disregarding safety functions, yet it seems clear a call must be made for a review of how CE AVRs are tested and what safety systems are mandated, perhaps with some consultation from manufacturers, people like THX, and other industry professionals.

Electrical Consumption

We also look at an AVRs idle power consumption since electricity use, especially as it relates to something "just sitting there" is of increasing importance to people.  Not surprisingly the numbers are slightly lower than last year's model:  the power-on consumption with no audio signal hovers right around 88 Watts in the default >6ohm speaker setting.  In the standby state its consumption is below what our equipment can measure so it can be assumed to be less than 2 Watts which is excellent!  As we expect, when switched to the >4ohm speaker setting idle consumption drops to just 56 Watts.  At first it may seem point moot since that setting is all but useless, however if using the 806 as a preamp/processor coupled to an outboard power amp, placing it in the >4ohm setting might shave a couple kWh off your power bill at the end of the year (or make you feel just a little less guilty if you leave it on by accident when not in use), and the unit gives off marginally less heat.

Please note and be aware though that if HDMI-Control is enabled, the 806 consumes no less than 50 Watts when in standby....all day, everyday.  The feature allows the 806 to "control" compatible equipment (say, turn on a TV for example), but would you really leave an incandescent lamp on 24/7 just for the convenience of not having to reach for its switch?

In Practical Terms

Setting up and using the Onkyo will, for most people, be simple and straightforward, especially if they make a connection to a monitor and plug in the Audyssey Mic: Do what it tells you and you'll at least be up and running with some competence.  For the neophytes, what I call the magic THX button will do the trick 98% of the time: keep hitting it till it says either movie/cinema, music, or game as need be.  For the more seasoned user, tools and tweaks abound.

In terms of subjective perfromance, I'll skip the poetic superlatives and just say it sounds good, plays loud enough, and stays clean.  Hard pressed will anyone be to find any practical shortcomings in this respect.


On the whole the 806 is a mixed bag when looked at as simply the next offering in a line of AVRs with a rich heritage.  There is no question that there is some value in the new video processor, value which unfortunately is undermined by its less-than correct video repeating, and while THX Loudness Plus (or Audyssey Dynamic EQ) are very compelling new features, clearly something has been given up in terms of amplifier power.

When looked at without prior prejudice, though, the 806 is a stellar value as an audio processor and is an excellent candidate on its own for smaller rooms, or strictly as a pre-amp if coupled with an outboard power amplifier.