Product Review

Onkyo TX-SR800 THX Select AV Receiver

April, 2003

by Brian Florian






SSP Section


Dolby Pro Logic II, Dolby Digital, THX Home Cinema, THX Surround EX, DTS (ES, Neo:6, 96/24)

Precision: 24-Bit/96kHz A/D, 24-Bit/192kHz D/A

2 Zone operation

Amplifier Section


Power Output (8 ohm, 20 Hz-20 kHz, FTC)
100 W/Ch

THD (Rated Power) 0.08 % (all channels)

Damping Factor (1 kHz, 8 ohm) 60

Frequency Response 10 Hz-100 kHz (+ 1 dB, - 3 dB)


Dimensions (W x H x D) 17 1/8" x 6 7/8" x 18 1/16"

Weight 42 Pounds

MSRP: $1,000 USA


Onkyo USA

18 Park Way

Upper Saddle River, NJ 07458

Phone: 800 229-1687

Fax: 201 785-2650  

Of Comfort and Assumptions

Money can't buy happiness. A platitude?  Sure, but if any of us is honest, we'd admit it is true, at very least in the empirical sense.  When I start to grumble about money (and I do so more than perhaps is my fair share), my wife is right on the ball to point out the wealthy couple in town who are getting divorced, the movie star who just got arrested and/or checked into rehab, or some other cliché of money failing the human spirit.

No sir, money doesn't buy happiness, but it sure can make you comfortable while you complain about your troubles.

In a similar fashion, spending oodles of money on your home theater equipment is no guarantee of performance (which I will equate to a sense of happiness in this case).  But, it does help people to be satisfied with their investment.  Countless times I've questioned the value of someone's purchase, only to have them come back and say, "But it cost so much . . . ." as if that were some iron clad certificate of quality.  That's an assumption, and everyone knows the saying about assumptions.

What about assumptions at the other end of the scale?  Many people assume that less expensive gear is sonically inferior.  More specifically, most anyone will assume that a receiver is categorically an inferior surround sound processor as compared to "dedicated" preamp processors.

Assume no longer.  Be ye not comfortable with lesser value.

The Goods

Over two years ago I set out on a quest.  Based on a firm belief that a "killer" surround sound processor preamp did not have to cost more than $1000, I started combing the market.  I'll steal just a little of my own thunder (because after all, it is my thunder) and tell you that in the Onkyo TX-SR800 receiver I have found the object of my quest!  Intrigued?  You should be.

So what exactly do we have here?

Looking at the rear panel, you will see that we've got the usual suspects.  Seven basic stereo inputs, three of which have rec-out lines, five of which have composite video, and S-Video.  There are three coax and three optical digital inputs which can be assigned to any of the analog lines, as can the two component video inputs.  A single 7.1 analog input is provided.  Yes, that's 7.1 input! I'm not sure what good it will be today, but you never know about someday next Tuesday.

In addition to seven channels of amplification, a full 7.1 pre-out set is available for connecting the TX-SR800 to outboard power amplifiers.  A single optical digital output is provided, and a set of 1/8" IR I/O jacks round out the set.

The TX-SR800 gives the user an interesting choice:  At your option, you can use the two center surround outputs as Zone2 lines instead.  So if you are happy with 5.1 or don't have the space, need, or desire for 7.1 THX Surround EX, you can have a true stereo Zone2, complete with independent volume control.  Even more interesting is that the speaker outputs follow suit, meaning you do not need to buy a stereo power amp for the Zone2 if you decide to go that route.

Click here to see a larger photo.

Click the photo above to see a larger version.

Oh, I nearly forgot, in addition to all that, a phono level input is provided for vinyl, antenna terminals are there for the radio, and there is yet another input on the front with stereo audio, composite and S-Video, and optical digital jacks.

The 42 pound weight is no joke.  The box even recommends two people handle it.  Almost all of the mass is in the power supply transformer and amplifier heat sinks.  While the bottom plate is a thick, rigid steel, and the the front panel is classic black machined aluminum, I was a little disappointed in the top cover and back plate.  A flick of the finger on the top produced quite a ring, and while making connections with tight RCAs or bananas, the back actually flexed a little on me.  On the other hand, the often overlooked volume knob instills confidence.  It has a nice solid feel, imparting a good sense of "mass" reminiscent of the machined steel volume knobs of the 1970s. In any case, I am very glad the weight is in the power supply instead of just a heavy metal box.

Click here to see larger photo.

Click the photo above to see a larger version.

The supplied remote is a "universal" in that it has built-in codes for most major bands of DVD players, cable box, TVs, and VCRs, but can also learn the signals from most other units.  All buttons can be illuminated, but the number pad (down at the bottom) doubles as a function selector for the TX-SR800.  So while the Onkyo function labels are on the buttons, the digits are silk screened above the buttons and thus can't been seen in a dark room, even when the remote's back light feature is on.  Personally, I'd Click here to see larger photo.have liked it better if the labels were the other way round just because I'm more apt to need the numbers in the dark.

The remote control is reasonably intuitive when it comes to controlling things.  <Click on the photo at the right to see a larger version.> Discrete input selection is available from the remote (and the front panel), while the transport buttons for DVD/CD/Tape are appropriately positioned and are shaped according to their function.  The cursor control of either DVD or the TX-SR800 is accomplished by moving the 4-way button at the very center of the remote in the direction you want.  Pressing the button equates to "Enter", while the "Return/Cancel" button is just above it.  Normally I really like this sort of quasi-joystick but unfortunately with this one, all too often I would get an "Enter" when I was trying to get a left, right, up, or down. Of course, one will get used to any remote over time, and the mistakes will end.

The Onkyo remote makes one cardinal remote control sin:  When in TV mode, the volume buttons control the TV's volume and not the Onkyo's.  Imagine changing channels, changing the remote mode to "Receiver", adjusting volume, changing the mode back to "TV", changing channels again, and so on, all evening long.  There needs to be a choice on the remote for whether A) the volume buttons are devoted to the Onkyo fulltime or B) the way it works now.

The audio computer is the two chip Fujitsu setup.  The main audio decoder is the Fujitsu MB86D41, a fixed point 32 bit processor capable of up to 110 MIPS.  In its on-board ROM are all the decoding routines such as Pro Logic II, Dolby Digital, Dolby Digital EX, and DTS/DTS ES.  The second chip is the Fujitsu MB86344B, also a 32 bit processor, capable of up to 121 MIPS.  This unit does all the "post" processing of the audio, such as bass management, time alignment, THX processes, and any other effects.

The TX-SR800 has a pair of 24bit/96kHz ADCs to convert two channel analog inputs to digital for processing.  At the opposite end there are six 24bit/192kHz DACs and one 24bit/96kHz pair.

As for the power amplifiers, Onkyo quotes each channel as being 100 watts into 8 ohms, 20 to 20,000 Hz, with 0.08% THD, and they qualify that by saying any two channels driven.  The decidedly large power supply is quoted by Onkyo as being about 1.1kVA and is coupled with 30,000µF of reserve.  We'll talk about how it actually performs later in this article.


It's no secret that at Secrets, I'm the token "THX guy", even though I don't unilaterally endorse everything THX.  A couple of years ago at a PR dinner I was placed at the same table as Paul Barton of PSB speakers, I think in the hopes that an entertaining THX pros/cons debate would ensue (for the record, both Paul and I were more civilized than that, discussing how scrumptious the meal was).

A bit of a refresher THX SSPs are often thought of as being units which simply include the "kit" of THX post processes applied to movie soundtracks after either Pro Logic (more recently Pro Logic II), Dolby Digital, or DTS decoding.  It is certainly true that Re-Eq, Timber Matching, and Adaptive Decorrelation are there.  What gets overlooked is the myriad of other "behind the scenes" parameters the units need to meet, but which, because manufacturers pay good money for the design manual, cannot be divulged in their entirety.

Beyond just simple THD and S/N ratios, which anyone can mandate and measure, THX units must have such goodies as test signals (white noise) which are a specific shape and output at a specific voltage, ensuring proper setup.  Output levels in general must meet both a voltage and impedance tolerance so that, when mated with power amplifiers which have a complimentary spec for their input, S/N over the whole system is maximized.  The THX 80 Hz crossover features a 4th order low pass to the sub and a 2nd order high pass to the mains, which when compounded by a THX speaker's own 2nd order rolloff, sums a perfect flat response with the least amount of phase shift.  Power amplifiers, including those in a THX Select Receiver like the TX-SR800, must be able to drive a certain impedance and efficiency of speaker to a set level in a certain size of room, and do so without compression or harmonic buildup which would alter the frequency response of the system.

And not all of the THX stuff is technical . . . .

In stereo audio, the white jack has always been "left" and the red one "right".  It took THX to do something as simple as set a standard for center, left surround, right surround, and subwoofer (green, blue, gray, and purple respectively).  More recently, cream and brown have been assigned to the two center surround outputs.  Seem trivial?  Maybe so . . . right up until you are fumbling behind an equipment rack trying to make a connection and can't read the labels.

I could go on and on, but I'm detracting from the TX-SR800, our subject at hand.  My point and reason for taking this little tangent is coming right up now . . . .

When THX Select was announced a while back, a plethora of criticism went out about THX "cheapening" their consumer electronics program as some evil money grab.  For the most part, those folks calmed down when Select was explained as being the exact same thing as Ultra, only spec'ed for a smaller size room.  It doesn't take a genius to figure out that means only speakers and amplifiers (and by proxy AV receivers) can be "Select-ized".  Try and find a THX Select preamp processor.  There are none, because the SSP requirements in the smaller THX Select room are exactly the same as the full size THX Ultra room.

People who think outside the box may be ahead on this one:  With a little extrapolation, you come to the conclusion that a THX Select Receiver, when used as a preamp/processor (by connecting it to outboard power amplifiers) is for all intents and purposes a THX Ultra preamp processor.

Is anyone besides me excited? I hope so, because writing reviews is a lot of work, and this is a great receiver.

Form and Function

The Onkyo TX-SR800 gets almost everything "right" when it comes to options, functions, and behavior.

For starters, time alignment gets set just the way we like it:  by inputting the distance to each and every speaker in the system, in 0.5 foot increments.  The Onkyo includes a global delay (a.k.a. lip-synch delay) to realign the sound with video which might have been delayed by a video processor or the scalers inside the current crop of digital displays (Plasma, DLP, LCD etc).  The range is 0-74 ms, which equates to almost 5 video fields in NTSC (1ms short).

As is the case with any SSP worth its salt, the TX-SR800 uses a digitally controlled analog volume control, permitting not only precise but also repeatable volume levels.  The Onkyo harnesses the convenience of its volume control by permitting the user to set a default power-on volume level (no nasty full-blast turn-ons the day after the teenagers have a party). Each input has its own volume trim of ± 12 dB.  A maximum volume level can be set (anyone with knob-obsessed infants is already loving this feature) and there is even an option for what exactly the mute button does You can choose between a total cut or a fixed reduction of -10 to -50dB (in 10 dB increments).  I have been asking some of the big name SSP makers for this simple convenience and I find it hysterical that a mass market receiver has beat some of them to the punch!

The front panel display is thankfully dimmable.  At the press of a button you can cycle through three brightness levels, the lowest of which is only just low enough for me, though any other LEDs currently lit up on the front also dim.  Too many times we've seen an SSP which would allow you to dim the display panel, yet leave a power LED beaming at full brightness.  Each input, except the tuner, can be renamed to anything you like, up to 10 characters, and you may also name the preset stations in the tuner.

The Pro Logic II Music non-mandatory adjustments are available to the user.  Panorama, Dimension, and Center Width can be set in the Advanced menu. Similarly, DTS:Neo6's Center Image adjustment is available.  We wish that hardware manufacturers would enabled the decoders to read the Surr.Encode flag in two-channel Dolby Digital (so far we've found only one that does).  The Onkyo is no exception and just ignores it.  It does however allow you to 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 Analogue/PCM material, "THX" on Dolby Digital 5.1, and "Pro Logic II" on 2 channel Dolby Digital.

THX Surround EX playback can be set to either "Auto", where we confirmed the unit does read the bitstream flag, or forced on/off.  Ditto for DTS ES.  When using the unit as a 7.1 playback system, you can choose what it does with the surrounds of any and all 5.1 sources.  They can be routed to the side surrounds, the rear surrounds, or both.  On the flip side, the TX-SR800 will down-mix 5.1 soundtracks to stereo for the sake of headphones, Zone2, or heaven forbid, if you find yourself with only two speakers for some reason.

THX's Re-Eq can be turned off independently of the THX Cinema/THX Surround EX mode, but unfortunately is a global choice (we'd prefer if it was a choice for each input).  The darn thing won't stick though; it resets to "on" whenever the TX-SR800 is switched off.  Also in the THX setup section is a choice of Dolby Pro Logic II Movie or DTS Neo:6 as the matrix decoding format when a two-channel source is present and THX Home Cinema is engaged.  Use Pro Logic II.  'Nuf said.

The mono listening modes are less than intuitive and unfortunately have logistical issues.  While "mono" may seem an insignificant topic these days, there are an awful lot of timeless classics in my DVD collection which have mono soundtracks.  The first of two mono modes offered on the Onkyo is called Mono Movie. It's one of those DSP soundfields that slaps a load of reverb and other nonsense onto the signal, essentially making it sound like you are in the movie theater with poorest acoustics in the world.  Curious is that it exhibits the DSP processing only if fed a two-channel signal (often a mono soundtrack is in fact carried by a two-channel bitstream).  If you feed this mode a true mono (a single channel) Dolby Digital bitstream, the DSP becomes benign and you get proper mono playback out of the center speaker.  The other mono mode offered is simply called Mono but it does not play through the center speaker.  It takes your choice of L+R, just L, or just R, and plays it equally from the front Left/Right speakers, thus making the mode inappropriate for movies.  While the TX-SR800 offers the Academy Filter, it does so only on the Mono mode which we just said is useless for movies, thus making the Academy Filter useless (for more information on Academy Filter, see our article Cinema Sound and EQ Curves). So ultimately if you A) have an old movie on DVD with a mono soundtrack and they assembled it as mono left/right, just use Pro Logic II Movie to decode it to the center channel. If B) you have a true mono soundtrack, use the Mono Movie mode.

Bass management follows the THX spec.  Each channel can be set either large (full range) or small (high passed) with the balance going to the subwoofer or, in the absence of a sub, main left/right.  The default crossover frequency is 80 Hz, but the Onkyo allows a selection of 40-120 Hz in 20 Hz increments.  Like most units, the Onkyo truncates the top of the LFE channel, so a crossover much lower than 80 Hz is not recommended.  For more information, please see our article Miscellaneous Ramblings on Subwoofer Crossover Frequencies.  In it we make a pretty good case for setting all speakers to "Small", setting them all to the same crossover frequency, and setting that frequency somewhere around 80 Hz.

As per THX requirements, the Onkyo attenuates DTS material by 4 dB, equating it with Dolby Digital material encoded with the default Dialnorm value of -27 .  While content differences between a Dolby Digital mix and a DTS mix can and do most certainly exist, it is important to at least put the two on a level playing field so that differences heard are exactly the differences in the mix.  Without attenuating DTS by 4 dB, the DTS track would always play louder and "strike" us as sounding better, even if it were absolutely identical to a Dolby Digital counterpart.  For more information on Dialogue Normalization, please see our article Dialogue Normalization: Friend or Foe.

At the start of a bitstream, the display will sometimes show the difference in Dialnorm assertion with reference to the preceding program.  So for example, if you see "Dialnorm: +4 dB", that means the output of the decoder has been raised by 4 dB.  The owners manual is misleading here, suggesting that in order to keep things at a constant level you should turn your master volume down by 4 dB when you see a message like this (page 51).  The whole point of Dialnorm is that the decoder makes the adjustment for you.  If the output of the decoder has been raised by 4 dB, it's because the present soundtrack is 4 dB lower than the previous. 

At the press of a button one can elect to run the unit in either Direct, or Pure Audio.  "Direct" simply means a total bypass of all digital audio hardware and thus, no bass management or subwoofer.  "Pure Audio" goes one step further by shutting down the video circuitry and even the front panel display.

On the Nature of Upsampling and Other Sundry Rants

There is an option to turn on Upsampling in the digital audio setup menu.  Somewhat the vogue these days, upsampling can't increase the real resolution or bandwidth of the information feeding the DACs, but it may decrease the requirements of the DAC's reconstruction filter by upsampling the digital audio to a higher sampling rate.

The TX-SR800's upsampling option only works with two channel PCM digital signals (not Dolby Digital).  Something to remember about upsampling is that it cannot put back information that was lost. If the upsampling occurs at a direct integer, the upsampling creates new samples in between the original samples, calculating estimated values based on some form of interpolation and a low-pass filter, which in turn makes following DSP and analog filters that much easier to implement.  To its credit, the TX-SR800 upsamples to direct integers (44.1 to 88.2 and 48 to 96). Upsampling to a rate that is not a direct integer of the original sample rate would require that the interpolation algorithms create all of the resulting samples, which means that without infinite processing power and bit length, the upsampling process actually loses information.  I asked fellow Secrets editor Sandy Bird to come over and do a little A/B'ing.  In the end, his assessment was the same as mine, the preference being, without exception, for upsampling in the TX-SR800 to be left off. Go figure.  The point here is that you should try features like this and don't assume you will necessarily like the results.

One interesting  feature is the subwoofer option for analog and pure PCM digital sources.  In the advance setup you can choose to override the existence of a subwoofer when listening to stereo analog audio or a PCM digital input.  I know from lurking on forums that many people feel music sounds better when they don't use their subwoofer.  As far as I am concerned, that simply means they do not like their subwoofer, but the crash boom bang of a movie soundtrack somehow masks that, making it "good" for movies but "bad" for music.  However, I am diametrically opposed to the very concept of a subwoofer being good for one thing and not for another.  The requirements imposed on a subwoofer are no different from one medium to the next.  Heck, pick any movie and pay attention to how often there is music (hint: rare is the scene which does not have music as an integral part of it).  So, while the feature may appeal to a select group of audiophiles, if in fact music sounds better with your subwoofer off, try a different location, adjust it, then repeat as necessary.  If music still sounds better with it off, pawn it and get a better subwoofer!

The only feature we could ask be added to this product would be A/D conversion of the 5.1 analog input for the purpose of bass management and time alignment of DVD-A material, given that the current crop of DVD-A and SACD players are for the most part deficient in what they provide for themselves.  In perspective though, this would require the TX-SR800 to have at least four more A/D channels, preferably six, and that would mean a hefty increase in the price of the unit if it were to be done at an acceptable level.  Hopefully, DVD-A players will soon start being made with their own proper bass management and time alignment at which time this will be moot, and the Onkyo's Pure Audio mode will perhaps really be a boon.


It's all a question of the DACs.  The Digital to Analog Converters present in today's digital AV decoders are the most influential element when talking about the subjective sound quality of the piece.  Not to diminish the role output devices have, but it is the DACs which are paramount.  When we connect a DVD Video player, or even a CD player for that matter, with a digital audio cable to an AV receiver, the sound we hear no longer has anything to to with the player and everything to do with the receiver.  More and more, the proverbial AV receiver is becoming the critical choice for sound quality.

On the whole, the TX-SR800 has a more natural sound and is less analytical than other receivers I've had occasion to listen to, and thus does not fall into the stereotype of what we have all been accustomed to in the past, with "mass market stuff".  I don't really like such arbitrary words as "airy" or "open" when trying to describe audio.  However, I do know when a French horn actually sounds like one and when soprano opera remains solid, both being decidedly the case with the Onkyo.

Never did my wife ask me to "go back a bit" during a movie because we missed what someone had said, testament to the unit's natural sound on dialog.

As we pushed the volume up, there was a fairly obvious threshold beyond which the receiver's amplifiers were not able to maintain absolute composure, somewhere around 6 dB below reference.  I'm not talking about clipping or other such extreme distress.  The unit can do ref level in the size of room the THX Select spec caters too and do so without noticeable change in spectral response.  It simply lacked that final "punch" when going for broke. But, that seems to be the only limitation of this receiver, and undeniably one of any receiver in this price range.

In perspective, despite my highly damped room, the loudest we ever watch a full length movie at is normally -13 dB, sometimes -10 dB if I'm in a testosterone mood.  This is well within the TX-SR800's range.

When for fun we connected the Onkyo to our outboard THX Ultra power amplifier, the results were commensurate with what we would expect from an excellent THX Ultra processor and a truly first rate preamplifier.

We spun the always demanding Andrea Bocelli DVD and listened for aberrations which usually cause me to squint, but we could find none, even at the nearly irresponsible playback level of 0 dB.  We tried in vain to get any distracting hiss from the noise floor:  During the near silent passages of the "Star Wars" soundtrack, all we got was a background of delicious, sonic void.  The dynamic, complex riffs of "Dire Straits" rendered with aplomb, and my staple, if somewhat compressed, Alana Davis and Amanda Marshall albums came through with the sort of believability that scares me.

"Moulin Rouge" had an exquisite reproduction of the track.  "Saving Private Ryan" came through with every bit the frightening sonic experience intended.  "Attack of the Clones" was immersive and had palpable sonic environments, even if the movie wasn't that great.

So, in the Onkyo, we found all the good ol' movie magic.


All in all, mono modes and remote control shortcomings notwithstanding, I simply cannot believe this unit is on the market for the entirely reasonable SRP of $1000 (and we've seen them street for less).  In fact, I'd call it an outright steal!   If you are looking for a killer AV receiver around the kilobuck mark, you owe it to yourself to check this product out.  If you like the idea of a THX Ultra SSP, but can't afford to spend $3500, you need not look any further than this.

The Onkyo TX-SR800 receiver is reference quality at the $1000 price point, both as a Surround Sound Processor and as an AV Receiver.

Kudos to Onkyo for a simply marvelous product.

- Brian Florian -

Reference equipment:

Paradigm Reference Studio/40 and Studio/CC speakers 
Paradigm ADP/170 dipole surround speakers 
M&K MX-105 Powered Subwoofer
Smart Theater Systems 2X150VT amplifier 
Rotel RB-985 5 channel THX amplifier 
Anthem AVM-20 Surround Sound Processor
Yamaha RX-V795a processor/receiver 
Apex 800 DVD player
Toshiba 2108 DVD player
Yamaha CDC-695 CD player 
Canare coax interconnects, Nordost Blue Heaven speaker cable and S-Optix video cable 
Sony KV-27S36 Trinitron TV 
Smart Theater Systems GC120 AC Line Purifier

Related to the article above, we recommend the following:

Miscellaneous Ramblings on Subwoofer Crossover Frequencies

Misunderstood 0.1 LFE Channel

Nature of Equipment Reviews

Dialogue Normalization: Friend or Foe

What we Hear

Why Time Alignment is Important

High Fidelity

Cinema Sound and EQ Curves

Accuracy, Distortion, and the Audiophile


Note: We have heard of some corporations using our articles and graphics to teach courses to their staff without authorization. Secrets articles and graphics are original and copyrighted. If you wish to use them in your business, you MUST obtain permission from us first, which involves a license. Please contact the editor.

Our Vault pages may have some display quirks. Let us know if we need to take a look at this page or fix a bug.
Connect with us
  • Instagram
  • Google+
  • YouTube
  • LinkedIn
  • Pinterest
Secrets "Cave"