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post #1 of 58 Old 08-06-2003, 11:58 AM - Thread Starter
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I'm looking at a receiver (the Onkyo TX-SR701), which has a THX processing mode.

It appears that you can choose this button (the THX button) when listening in Dolby Pro Logic II, Dolby Digital 5.1 (including EX), or DTS (including ES).

It appears to layer the THX on top of the normal processing? I'm not sure what it does? What is the advantage of utilizing the THX mode instead of the standard PLII, or DD 5.1 or DTS?

To further confuse things, when engaging THX in a 5 channel source (i.e, dd 5.1 or DTS), it refers to THX as "THX Cinema".
If DD 5.1 EX, it is called "THX Surr EX". If DTS - ES, it is called DTS - ES (THX).

Right now, with my non-THX Onkyo receiver, I typically listen in "Pro Logic II Movie" mode, when watching regular cable TV. If I engage THX so it is "PLII (THX)", what exactly is different? Does it really change the sound in anyway?

Similarly, what happens when I listen to a DVD in DD 5.1 or DTS (lets forget EX and ES for the moment) and then engage the THX button -- so it changes the mode to "THX Cinema". What happens to the sound.

Is there really any reason to listen to "THX Cinema" as opposed to standard DD 5.1 or DTS?

What does THX do when it is a DD 5.1 EX source, or a DTS ES discrete or matrix source?

Can someone explain exactly what THX is doing to the standard listengin modes such as PLII Movie, DD 5.1 and DTS? Is there any real reason to use the THX processing? Is the sound difference noticeable?
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post #2 of 58 Old 08-06-2003, 12:13 PM
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In THX mode, your receiver is doing a few things.

Timber Matching. The output of the surrounds is shaped to more closely match what we hear from the fronts (even with identical speakers, the ones behind us will sound different because of the shape of our outer ear etc etc).

Adaptive Decorelation. If (and only if) the signal being sent to the two surround channels is identical, they will be altered one from the other, ever so slightly, to alleviate the "in your head" effect and maintain a spacious, broad surround sound field. Adaptive Decorelation does not apply to THX Surround EX or DTS ES Matrix (THX) modes since identical signals in the left and right surround get decoded to the center surround (aka "rears").

Re-Equalisation. This one item is separately defeatable from the others in late model Onkyos (and other THX units). Re-eq applies a slight attenuation of the highest frequencies in order to get the sound to more closely match what was originally intended by the sound artist. We have an extensive article which discusses the whys and wherefores of this:

Learning from History: Cinema Sound and EQ Curves

Please, PLEASE, PLEASE note that the above listed THX post processes are NOT, say again and again NOT the only thing that makes a THX SSP or Receiver a THX unit. THX processors must, among other things, adhere to certain tolerances for i/o impedances and voltages so that the various pieces (SSPs, AMPs, Subs etc) all work together in a way that maintains a nice S/N ratio. Receivers and amps must be able to swing enough voltage and current to drive THX speakers to a certain level in a certain size room with out distortion, harmonic buildup, or dynamic compression. THX units must use a specific set of high and low pass filters in their bass management which work in concert with the response of THX speakers to create a sharp and phase-correct 4th order butterworth splice between satellite's and subwoofer....And so on and so on....
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post #3 of 58 Old 08-06-2003, 12:31 PM - Thread Starter
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Okay. That is the theory.

But should one (with a THX receiver like the Onkyo 701) normally engage THX when watching a DVD that is DD 5.1 and/or DTS to achieve the "best" or "most accurate" sound? Or would you really only gain an acoustic advantage if the DVD is a "THX" DVD -- i.e, they used THX standards in the making of the DVD sound? Does it matter if the DVD is DD EX or DTS ES -- does that change how or when you would use THX?

Or would one generally want to apply THX to ANY DD 5.1 or DTS DVD?

Also, what about Pro Logic II? Would one generally want to (or should one) engage THX mode when listening to say regular cable TV -- which I normally listen to in PLogic II Movie? Would THX have any real benefits in that situation?
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post #4 of 58 Old 08-06-2003, 12:47 PM
 
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Simple. If the movie sounds bright and harsh, engage THX. Jurassic Park is an example of a movie that is REALLY harsh. Most THX DVDs will rip your head off.

THX is highly controversial to say the least and is simply unnecessary to achieve high fidelity in an HT environment, but it DOES come in handy if the movie is too bright. THX movies are mixed too bright on purpose and therefore require THX processing to sound good in the home.
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post #5 of 58 Old 08-06-2003, 12:55 PM
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caesar1,

THX Post Processes are intended for all soundtracks. The THX mastering program for DVDs (and formerly Laserdiscs and VHS tapes) has to do with ensuring the master is created under proper standards and that the duplication process is up to snuff (though the dublication thing is not really as much an issue with DVD as it was with Tapes and Laserdiscs).

Personally, I leave THX on all the time. Every movie. Every TV show. The post processes are unilaterally beneficial for multichannel soundtracks (and that includes TV being Pro Logic II decoded). Some say that Re-Eq takes too much treble away from some material (some of New Line Cinema's releases claim to be remixed for home and not need it) but if you read my article, I explain how Re-Eq (using it or not using it) has more to do with your room than the media.
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post #6 of 58 Old 08-06-2003, 01:26 PM - Thread Starter
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Quote:
Originally posted by Brian Florian
caesar1,

Some say that Re-Eq takes too much treble away from some material (some of New Line Cinema's releases claim to be remixed for home and not need it) but if you read my article, I explain how Re-Eq (using it or not using it) has more to do with your room than the media.
There is a separate Re-EQ button on the Onkyo remote, which allows one on the Onkyo 701 to turn on or off Re-EQ. So it looks like you can egage THX, but not Re-EQ if you so choose (unless that is disabled under THX)?
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post #7 of 58 Old 08-06-2003, 01:59 PM
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Yup. Same on my Onkyo TX-SR800. You can turn off Re-Eq if your ears tell you to, while maintaining the benefits of the other THX Post Processes.
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post #8 of 58 Old 08-06-2003, 02:04 PM
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brian,

i agree with you on THX Post Processing feature. I have a Denon AVP8000 Pre/pro DD/THX (no DTS). i have tried with various surround processing modes with every DVD movies i have ever watched with my 8000, with THX mode engaged it seems that movies sound/feel like movies...like u watch it at the theater. often time i've noticed people confuse THX Post Processing (software) with THX Certified equipment (hardware).

question, what is your opinion about the current THX (Ultra and Ultra II)Post Processing compare to Logic 7 by Lexicon (not HK)? Have you heard Circle Surround II found on Theta Digital Pre/Pro and Marantz receivers? any opinion?
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post #9 of 58 Old 08-06-2003, 02:34 PM
 
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Brian,
I would have to disagree strongly with the "unilaterally beneficial" comment. That would be subjective. If you have a bright room or bright speakers, then yes. Brian, what system do you have? On my system, THX would dull the sound unacceptably. It's like saying "turning the treble down is always beneficial to the sound".
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post #10 of 58 Old 08-06-2003, 03:34 PM
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John,

If you scrutinize my post you'll see that the comment you are referring to immediately follows me saying that I (emphasis on that "I") use THX Cinema all the time. In other words, THX Cinema is of unilateral benefit to what I (again that "I") listen to (in terms of multichannel motion picture soundtracks anyway). Guess I should have been more explicit in my phrasing. I did however go on to say, as you do, that one may find Re-Eq results in too much high frequency attenuation for a given environment. Those of us with units which allow Re-Eq to be disabled independently of Timber Matching and Adaptive Decorelation (which I feel are always welcome regardless) have it made in the shade as it were.

I'd like to invite you to read our article which I linked to in my first post. By the end you get all the facts about Cinema Soundtracks, EQ Curves, and what Re-Eq is and is not. Let me entice you: Did you know that, contrary to all of THX's literature, movie soundtracks sounding too bright has nothing to do with the fact that they were mixed for a commercial theater equalized to the X-Curve?..... :)
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post #11 of 58 Old 08-06-2003, 04:02 PM
 
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That's an interesting article, I'm still digesting it. What pisses me off is that it indicates that most of what I've read from "journalists" (no offense, but *most* A/V journalists know far less about audio than me, a good old "sales hack") and THX is just plain BS. However, in my brief scan I didn't see anything about dealing with the screen, and I didn't see even a reasonable mention of DTS. I guess I don't think getting info from Dolby means you can't mention DTS's contributions to theater. And, the way *I* remember it, Jurassic Park and DTS came out before Dolby Digital, but it's been awhile.

BTW, if you didn't notice, I DESPISE THX. And, quite frankly, don't think much of Dolby either. Did you notice how Dolby basically claimed that AC-3 was essentially lossless subjectively and the PCM is totally transparent, BUT now they're hocking MLP which is "better than CD". I know Dolby had contributed a lot, but sometimes, they're just so full of crap. But not NEARLY as full of crap as THX. THX tried to sue Sherwood and Yamaha for using 6.1 processing without the THX label. So much for the concept that they're just all about the sound. Oh well, just venting. But you just gave me one more reason to despise THX, like I needed one of those.
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post #12 of 58 Old 08-06-2003, 04:20 PM
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Billie,

Although I have to say that I'm not impressed with some of the recent tangents THX has taken, your comment "it seems that movies sound/feel like movies" really hits home when we consider the original THX mandate: to make movies sound the way they are supposed to. :)

As to your question about Logic7 versus Ultra2, to be honest with you, I'm a bit anal when it comes to cinema sound technology and my movie soundtracks. If its 5.1 thats how I play it. If it was Dolby Digital Surround EX encoded, then I'll do the THX Surround EX thang. Of course, I turn right around and LOCK Pro Logic II Music on for all my music. I've got my theater sounding so tight with the Auralex acoustic wedges that I actually NEED to create some ambiance. :)
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post #13 of 58 Old 08-06-2003, 04:38 PM
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John,

When you say "dealing with the screen", do you mean what I call "screen lose", the attenuation due to the speakers being behind a screen in the cinema? The cinema is Eq'ing any way so thats not an issue when it comes to the end result frequency response (though it does tend to call for robust tweeters and active bi or tri amplification :)).

As for DTS, me not mentioning them had nothing to do with the fact that I got some of my hard data (x-curve specifics for example) from Roger Dressler. The topic was eq curves, standardized playback, and such, none of which DTS made any particular contributions to. Dolby on the other hand has been responsible for the way audiences have been able to enjoy movie soundtracks for the past several decades, as well as providing the very foundation of this wonderful hobby of ours (where would we have been 10 years ago without Pro Logic:)).

Only since you mentioned it, Jurassic Park: 1993. Batman Returns: 1992. Both companies of course were working on and demo'ed their respective systems prior to that but if one wants to get picky....:)
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post #14 of 58 Old 08-06-2003, 04:46 PM
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John,

Just to keep things friendly....

"Oh well, just venting. But you just gave me one more reason to despise THX, like I needed one of those."

While I do subscribe to the tenets of their home audio paradigm, like I mentioned, I don't like the lateral moves they've been making lately. PC speakers....car audio.... Whatever guys! Also, THX's showings in DVD players is embarasing. Does anyone remember the Pioneer DV-09? :)

This is the east coast....got to get some sleep...catch you guys in the morning...
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post #15 of 58 Old 08-06-2003, 07:44 PM
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I think one reason the THX enhancement is so bright is to make the sound get thru microperfed screens better (in commercial theaters and those who have a perfed screen in their home theater).

A veteran is someone who, wrote a blank check Made Payable to 'The USA, ' for an amount of 'up to and including their life.'
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post #16 of 58 Old 08-06-2003, 08:09 PM
 
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Quote:
Originally posted by Brian Florian
While I do subscribe to the tenets of their home audio paradigm, like I mentioned, I don't like the lateral moves they've been making lately. PC speakers....car audio.... Whatever guys! Also, THX's showings in DVD players is embarasing. Does anyone remember the Pioneer DV-09? :)
Thank GOD. I'm so happy not to be the only one who thinks this.......
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post #17 of 58 Old 08-06-2003, 09:44 PM
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Quote:
Originally posted by hometheaterguy
I think one reason the THX enhancement is so bright is to make the sound get thru microperfed screens better (in commercial theaters and those who have a perfed screen in their home theater).
There's no THX enhancement that brightens the sound. In fact, quite the opposite: Re-EQ rolls off the treble in order to tame bright soundtracks.

Best,
Sanjay

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post #18 of 58 Old 08-06-2003, 09:55 PM
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Thanks for the correction Sanjay.
Quote:
THX movies are mixed too bright on purpose and therefore require THX processing to sound good in the home.
What I might have meant is from John's quote movies with THX on the label are mixed bright and harsh to get the sound thru the perfed screens. To my knowledge RE-EQ is only a home enhancement, and not in the theaters. Am I wrong?

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post #19 of 58 Old 08-06-2003, 11:04 PM
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You guys have to understand THX doesn't make the soundtrack or intentionally boost the EQ of the movie. All they do is watch over the process of the movie going from film to DVD they don't force stuff like a treble boost on film companies. They just watch and go the extra mile to make the DVD looks the best but you can have a good looking DVD without THX mastering but I've yet to see a THX dvd that looked bad.

In fact now that I remember I own a THX certified DVD that has had the treble boost taken out of it. The movie is "Tombstone The Director's Cut" and when I watched it with THX on I noticed that the gunshot didn't sound right and the classical music especially the Xylophone (I played that in HS) and the strings didn't have the upper end and didn't sound right so I turned off it and sounded perfect. This is before I did acoustic paneling to get rid of the brightness and slap echo in my room. IMO I think the THX re-EQ is to steep of a rolloff for my room and I use a Klipsch Reference setup and they ae supposed to sound bright and made even worse by my bright room, but it's still better than not having the rolloff and wincing evertime there's a swordfight. For example if you own Gladiator watch the scene at the end of chapter 4 where the emperor is practicing his swordfighting without THX at a loud level and you'll cover your ears because of the treble boost but it's much more bearable with THX.

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post #20 of 58 Old 08-06-2003, 11:46 PM
 
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Daniel,
Well, THX seems to change its rules from moment to moment depending on how much money is coming in, but it *used* to require that the mix be identical to that used in the theater. IOW, not remixed for home use as THEY wanted to do that with THX processing. But it wouldn't surprise me if they dropped that requirement to gain the support of a studio or two. Or at least suddenly became "flexible". Maybe it was a "THX Select" Disc
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post #21 of 58 Old 08-07-2003, 02:54 AM
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Quote:
Originally posted by hometheaterguy
What I might have meant is from John's quote movies with THX on the label are mixed bright and harsh to get the sound thru the perfed screens. To my knowledge RE-EQ is only a home enhancement, and not in the theaters. Am I wrong?
Movies in general are mixed bright for theatrical release, this doesn't have anything to do with THX.

THX certification for home video software (laserdisc, VHS, DVD) is simply a quality assurance program that tries to monitor and control the mastering process so that the resulting transfer comes as close as possible to the original master that was submitted. Nothing more. It doesn't have anything to do with how the films were "seen in the theatre", which has never been a requirement of the THX mastering process. If it had been a requirement, you couldn't have direct-to-video titles ('Armitage 3', 'Queen: We Will Rock You', the 'Tenchi Muyo' series, etc) that were THX certified; after all, how are you supposed have the mix be identical to that used in the theater if the film was never released theatrically?

Even if a movie soundtrack has been changed from the theatrical version and re-mixed for home use, as was done with the movie 'From Hell', it can still be submitted for THX certification. All THX will do is make sure that the resulting DVD comes as close as possible to the audio/video master that was submitted. If the theatrical treble boost is in the master tape, it will be on the DVD. If it has been equalized out, then it won't be on the DVD. If you submit a master tape that has the left front and left surround channels combined, as happened with Disney's animated 'Tarzan', then the resulting THX certified DVD will be a perfect match and have the same exact problem. (The problem was fixed on the later Special Edition.) They match input to output; they don't tell studios or film makers how to mix their soundtracks.

No quality assurance program has ever been 100% perfect, and THX won't be the first. Still, THX titles have consistently looked and sounded good; an impressive track record for their software certification program. Also keep in mind that there is nothing to stop non-THX titles from having higher quality than THX standards. Same with pre-pros and receivers: while the THX ones meet certain quality standards, there's nothing to stop manufacturers from producing even better products. Remember, it's A standard, not THE standard.

While there are a few things about some of the THX cerification programs that I consider useless (like approving DVD players plagued with the chroma bug), I can't see any reason for bashing everything associated with them. There are genuine things to criticize about THX; no need to make stuff up that's not true (e.g., they boost the treble, they drop requirements to gain the support of studios, their DVDs will "rip your head off", etc).

If you want an explanation of the THX software certification process, you can check out their brief articles on digital services and mastering. It will give you an idea of what's involved.

Best,
Sanjay

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post #22 of 58 Old 08-07-2003, 06:38 AM
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I think that if you read the link provided by Brian Florian it is clear that the THX processing is at best a comprimise. Along with there theory about dipole speakers, etc; they are trying to make our home theraters sound like a 'real' theater, without knowing anything about are room acoustics. If rooms are properly treated they may have no need of 'post-processing'. And in any case I would think that this should be some variable control, rather than an on/off thing. I have a Sunfire pre/pro; they are not "THX"; but there treble control is designed with a slope, etc to allow a similar but variable reduction in high freq content should it be required. This is explained in a recent post here on this forum by "Sunfire Engineer", a VP of engineering for Sunfire.

As far as QC, etc, I think its all a lot of hype. For example, I would much rather know power amp ratings into 2, 4, and 8 ohms with all channels driven simultaneously than the ambiguous spec that THX lets manufuctures get away with (like into 6 or 8 ohms, with no specified power for all channels driven).

I also prefer my surround speakers to be direct-firing rather that dipole. If you follow THX spec, you'd have to get a seperate set of speakers for surround music formats, if you want them to sound like they are mixed.

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post #23 of 58 Old 08-07-2003, 07:02 AM - Thread Starter
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Very interesting discussion. What am getting out of it is that THX mode should generally not be utilized, but perhaps re-eq should be turned on, depending on whether the source sounds "bright".

Maybe I should look at the Onkyo 601 (not the 701). The 601 is 85 watts as opposed to 100. But costs a lot less, as it lacks THX certification and THX modes.

701 has pre-outs, but I will probably never use them. So the 601 may be good enough???
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post #24 of 58 Old 08-07-2003, 07:10 AM
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Quote:
I also prefer my surround speakers to be direct-firing rather that dipole. If you follow THX spec, you'd have to get a separate set of speakers for surround music formats, if you want them to sound like they are mixed.
I certainly respect your opinion (I used monpole surrounds for many years) but I will say that you are mislead when it comes to "needing" direct radiating surrounds for music because thats what the sound artist used. Let me explain.

Unfortunate but true is the fact that many, many dipole speakers are improperly designed. Many manufacturers who make excellent conventional speakers have put together dipoles without knowing the fundamentals. These designers have simply taken one of their existing bookshelf models and placed a second set of out of phase drivers on the back. They many have revised the volume of the enclosure or angled the baffles but thats not the important piece they've missed.

Unlike a normal speaker where we are primarily concerned with the sound in front of it, proper dipole design (no coincidence, as mandated by THX) calls for a flat spectral response as a function of total power response. That is, the sum total of the sound coming from it in all directions.

A proper dipole and equivalent monopole, evaluated side by side, will not result in the monopole having more subjective "detail", nor will the dipole sound muffled or have a curtailed high end. The spectral response will be the same. The difference will be the directivity of the sound only.

Simple experiment: Take some dipole speakers and put them on your speaker stands (if you have any) where your main left and right normally are (point the nulls at you). Play some music. IF (and that is a big IF) the dipoles are properly designed, you should be perfectly satisfied to sit there and listen to some music. The soundstage will be somewhat vague but you should still get some imaging, the treble should be all there and the midrange should not be muddy.

All that said, using proper dipoles to listen to multichannel music IN NO WAY undermines the efforts of the sound artist. Properly setup monopoles, as found in many multichannel music mixing facilities, will be such that their sound is VERY broad in its stage (since two speakers is not enough to image over the arc occupied by the two surrounds). In other words, very similar to what dipoles produce.

Cheers and happy listening,
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post #25 of 58 Old 08-07-2003, 07:25 AM
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For example, I would much rather know power amp ratings into 2, 4, and 8 ohms with all channels driven simultaneously than the ambiguous spec that THX lets manufacturers get away with (like into 6 or 8 ohms, with no specified power for all channels driven).
?!? THX does not police what manufacturers put in their literature, or how the manufacturer choses to quote amplifier power. Don't "blame" THX for the less scrupulous marketing of various manufacturers. Lets find a GOOD example....here we are....Bryston 9B (a THX amp): 120 watts into 8ohms, 200 watts into 4ohms, all channels driven (full spectrum). Here's another: Aragon 3005: 300 watts/ch into 8 ohms at less than 0.02% THD (20Hz-20kHz - 3 channels driven), 500 watts/ch into 4 ohms at less than 0.03% THD. I HARDLY call those "ambiguous" specs.
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post #26 of 58 Old 08-07-2003, 07:33 AM
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Brian,

Perhaps, but it seems to me that mounting dipoles for mains and pointing the null towards the listener is a sort of "splash the sound off the wall" effect that Bose 901's are infamous for.

As far as movie sound goes, if I had speakers mounted directly to my sides that would be one thing. If I mount them (in a relatively small room) behind me and pointing at me I find I feel 'surronded' by the effects. Adding two more monopoles for back channels in a larger room would seem to fill that sound in further (I don't have this setup, but it makes sense).

I've noticed that two magazines that I subscribe to couldn't be more opposite as far as movie sound philosophy goes. Sound and Vision seems to be proponets of THX type speaker layout, while Widescren review is the opposite; all speakers the same, equidistant, etc. Obviously some pretty informed people in both camps.

My high-end audio-video dealer (sells Levinson, Revel, B&W, Lex, Linn, etc) has most of their rooms setup with monopole rears, using dipoles for side speakers in some cases (with non-THX 7 channel systems like the older Proceed AVP or Sunfire).

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post #27 of 58 Old 08-07-2003, 07:36 AM
 
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A proper dipole and equivalent monopole, evaluated side by side, will not result in the monopole having more subjective "detail", nor will the dipole sound muffled or have a curtailed high end. The spectral response will be the same. The difference will be the directivity of the sound only.
A properly designed dipole doesn't allow itself to be heard, only the wall behind you (and, unfortunately, the wall in front of you). And, THX has NO IDEA what the FR of the back wall is. Is it brick? Plaster? Sheetrock? Wood? So, the moment "accurate" sound leaves the dipole, it is immediatly essentially ruined. I have heard no dipole yet (and I've done to show the inferiority of dipoles) that sounds nearly as good as inexpensive bookshelf speaker. All dipoles were set up "properly". I suggest that the theoretical "proper dipole" that can be as accurate as a monopole simply doesn't and can't exist. But, if you feel it's more "involving" that's your choice. I am out in the field installing things and dealing with harsh reality. But, if you know of a dipole that is musically accurate and that people would sell their monopoles for, I'd like to know about it. Sorry Brian, I think you're spending too much time too close to that Ivory Tower.
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post #28 of 58 Old 08-07-2003, 07:41 AM
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Originally posted by Brian Florian
?!? THX does not police what manufacturers put in their literature, or how the manufacturer choses to quote amplifier power.
Why not police that? Isn't that what "standards" are for? If THX can require manufacturers to meet certain standards for amplifier power (all channels the same, more than "X" number watt/channel, etc), why can't they require that they be quoted consistently. Look at the THX specs for Denon's flagship reciever, for example. Will the thing even play into low impedence speakers? I'm sure it will, but you cant' tell from the spec. The whole concept of THX setting up standards makes no sense to me unless they are truly reprentative of something important, as far as my ability to evaluate the product's performance.

I'm not saying that there aren't some great THX cerified products out there, I just don't think that they are great because of THX.

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post #29 of 58 Old 08-07-2003, 08:00 AM
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Sorry Brian, I think you're spending too much time too close to that Ivory Tower.
Where exactly does that come from?

I've worked with a whole variety of speakers in several different rooms in my years as a reviewer. Am I not entitled to an opinion free of the type of comment you just made? Do you really think I like using dipoles just because THX calls for them? Did I not say that THX DVD players suck? Does that sound like a person "too close to that Ivory Tower"? I don't even own a set of THX speakers! All Paradigm stuff right now it case you are interested.

Incidentally, people were using dipole speakers in the surround role before THX did anything in the home audio market. They didn't invent them or anything.
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post #30 of 58 Old 08-07-2003, 08:10 AM
 
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Whoa, geez, Brian, I guess I must have a rough delivery or something. No, I was just saying that there's theory and reality and I've just had a hard time getting theory to work like many people in the writing profession say it does. Maybe I'm just an "idiot" as I've been called here (amazingly regularly, I might add). I actually have been enjoying your opinions and the article you posted was quite informative. I just don't happen to agree on the dipole thing and I think you occasionally, probably unintentionally, overstate a few things and all I did was offer a different viewpoint of it. Geez, I retract the statement! Sorry!!! You know us Americans, we're just wild west cowboys with no sense of international decorum :)
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