“We are the art gallery curators,” announced Tom Holman at the first home cinema dealer training I attended at Skywalker Ranch in Marin County, CA in July of 1995. Many readers will know that the mastermind behind THX (whose initials formed the ‘TH’ of the three-letter logo) probably contributed more to our academic understanding of what a home cinema actually is than any other living audio engineer or acoustician. Of course, it’s fitting that Holman is now the guru at Apple’s audio labs, and his ongoing research into psychoacoustics and multi-channel sound reproduction will certainly continue to promote its long-lasting and reverberating effects.

With quadrophonic audio for the most part already consigned to the trashcan of history by the late 1970s, but with matrix Dolby Surround processors starting to find their way into living rooms by the late 1980s, it was becoming clear that a unified theory – for want of a better term – was needed to address the misunderstanding surrounding multi-channel audio in the home. By 1993, Dolby Labs conducted a non-scientific home survey into its employees’ surround speaker arrangements, only to find that the type and placement of those speakers were pretty inadequate to say the least.

THX formulated a plan for professional cinemas in 1983. George Lucas decided that the complex mix of Return of the Jedi should be presented optimally in as many theaters as possible. For a cinema operator to have a screen ‘THX-Certified’ and be able to show the legendary Broadway ‘Deep Note’ trailer before a feature – and under licence – theatrical exhibitors had to conform to a number of strict rules. These revolved around achieving nothing less than excellence in film presentation and realizing “what the director intended” (a term originally coined by Lucasfilm marketeers but frequently borrowed since). To extend the art gallery metaphor in the opening paragraph, Tom Holman would also explain that, “if the filmmakers are the painters, then THX are the picture framers.”

A THX cinema had be able to reproduce dialogue accurately and intelligibly, elicit the “quietest whisper to the loudest explosion,” be agnostic to audio or vibration leaks from adjacent auditoriums, and mitigate background noise to a measurable NC30. Even the viewing angle to the screen from every seat in the house should be no less than 32°. The THX team provided a number of design services and recommendations for each customer, which included details of how to build double-stud walls and a behind-screen baffle, plus an approved list of amplifiers and speakers which could be deployed to achieve reference level audio. A proprietary THX crossover was also mandatory in every projection booth, which in turn had to be furnished with a double glass enclosure to mask the sound of a 35mm projector from the audience. This is merely skimming over the surface, but a THX engineer had to measure all the results in a finished auditorium with his accompanying ‘R2 analyzer’ before granting certification.

The challenge, however, with developing a home theater system (which achieved the same goals as the professional version) was how to play back a film soundtrack in a small room that was originally mixed in a large room and was designed to be played back in a large room. The results of Holman’s research led him to design an architecture of hardware and electronic features to solve those problems.

A 4-channel matrix Dolby Surround (or later discrete 5.1) AV preamp or receiver must contain a proprietary circuit which included signal processing with three primary functions: Re-EQ, Decorrelation and Timbre Matching. Re-EQ was an electronic predetermined roll-off which took the edge off the shrillness of film soundtracks. High frequencies are extended in a film mix so they can carry in a large room or professional cinema. Decorrelation split the two mono rear channels to add a sense of spaciousness in the surrounds and Timbre Matching negated the effects of tonal shifts as sounds pass from in front of our ears to behind. A steep roll-off crossover of 80Hz was also the optimal point at which a subwoofer should take over from the five main channels with non-directional audio and effects, and took place after the primary signal processing. (The 80Hz recommended crossover position is now a feature of all modern-day AV receivers.)

These electronic features worked seamlessly with a number of physical attributes in the speaker designs themselves. The front LCR speakers should have focused vertical dispersion, minimizing floor and ceiling first reflections, and therefore enhancing dialogue intelligibility and lending precision of audio cue placement in the front soundstage. The surrounds were dipolar in design, had to be placed to the sides of the listener in the ‘null’, and could replicate the array of side and rear wall speakers in a professional cinema.

While the focused vertical dispersion characteristics of the LCRs were extremely effective on film soundtracks, there was a corresponding compromise in their ability to image well on two-channel music sources, leading to much controversy in the hi-fi press. Furthermore, dipole speakers arguably became less relevant with the advent of 5.1 discrete audio and its accompanying split surround information. Both speakers and power amplifiers were only passed for certification – and licensed – if they could replicate the entire accepted audible hearing range of 20Hz to 20kHz and achieve flat response across the spectrum.

Although the landscape – or soundscape – has changed dramatically in recent years, particularly with the arrival of object-based audio in both the cinema and home, the fact is that a lot of THX’s rulebook still applies in one form or other to both environments. Much of the doctrine is now in the public domain, but Tom Holman’s work during those early years rarely gets the recognition it deserves. As a dealer trainer in the mid-1990s at Lucasfilm, I can say with certainty that there was always a moment of realization as attendees started to process the scale of the project THX had undertaken. Putting on a movie show that a filmmaker will be proud of is a worthy cause, and one that those who purport to love the art of film must never overlook. There will always be a role for the art gallery curator.

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Jonathan Burk

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Good memories. I can still remember the ad spread for the original Technics home THX system, and my appreciation for the THX Laserdisc certification program.

And my disenchantment when the certification program was expanded to VHS tapes...
 
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Martin Dew

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I really wanted that first Technics controller and power amp back in the day, Jonathan. Nice looking kit with the grey textured body and red THX logo on the blue front panel display. I can't find a pic of it online unfortunately.

I can tell you that not many of us were happy with the VHS certification program! That was pushing it a little too far...
 
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Brian Husar

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Thank you for this. I am so nostalgic for THX that my surround system is the Logitech Z906 because it’s THX Certified. And also affordable for me. I don’t like what Razor is doing with the name, although they have that Cinemark partnership and now they have there PLF theater. Lucasfilm should have never sold it. They don’t certify blu ray or 4K UHD blu ray like they did Laserdisc. I don’t even know what they do now?
 

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Good memories. I can still remember the ad spread for the original Technics home THX system, and my appreciation for the THX Laserdisc certification program.

And my disenchantment when the certification program was expanded to VHS tapes...
I think the THX Certified VHS tapes is because the transfers came from the THX certified laserdiscs. I could be wrong but I’ve become obsessed with Laserdiscs and I decided to see if my theory was correct and I noticed, for example that Patton was rereleased on LD sometime in the 90s and it was THX Certified, and at the same time Fox, or now 20th Century Studios, thanks Disney, they rereleased Patton on VHS as part of their VHS “Widescreen Collection” and the VHS was THX certified. At least that’s my theory. Martin can probably explain THX VHS tapes.
 
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THX Laser Disc was a small business unit within the THX Division in the mid-late 90s consisting of a studio relations manager, tech guru Dave Schnuelle and, for a while, yours truly overseeing quality control when I first joined. If I found visual anomalies and artefacts, or audio problems, I would catalogue the bad pressings and we could identify which plant (at Pioneer Japan or elsewhere), and which machine was responsible. So...with THX Laser Disc, we did guarantee quality through the whole workflow to the finished disc. I think I scrutinized every single pressing of the Jaws CAV collector's edition (of which I'm very proud as it's my favorite movie!).

When VHS came along, the packaging stamp was 'THX Digitally Mastered' because the only part of the chain we could reasonably control was the master itself, as we could hardly have eyes over the many duplication facilities and millions of copies shipped. VHS was also prone to degrading quality over time through head wear, so the compromise made sense, but we got some grief for the new strategy from both the press and home theater enthusiasts.

So, Brian, yes you're basically correct because the approved master that was used for the LD was almost certainly the one to be used on the VHS edition of the same title.
 
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JohnRice

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One of the main things I recall was that prior to THX, the volume level of soundtracks could be all over the place, especially on LDs and DVDs. That was one of the things THX resolved, and now there seems to be almost an industry wide standard, at least a lot closer than there used to be.
 

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My old Kenwood VR-8070 was THX "Select". I still have it. I suppose that was a label for lower priced receivers back then. I always enjoyed the old THX intro to some of my DVD's.
 
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Brian Husar

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THX Laser Disc was a small business unit within the THX Division in the mid-late 90s consisting of a studio relations manager, tech guru Dave Schnuelle and, for a while, yours truly overseeing quality control when I first joined. If I found visual anomalies and artefacts, or audio problems, I would catalogue the bad pressings and we could identify which plant (at Pioneer Japan or elsewhere), and which machine was responsible. So...with THX Laser Disc, we did guarantee quality through the whole workflow to the finished disc. I think I scrutinized every single pressing of the Jaws CAV collector's edition (of which I'm very proud as it's my favorite movie!).

When VHS came along, the packaging stamp was 'THX Digitally Mastered' because the only part of the chain we could reasonably control was the master itself, as we could hardly have eyes over the many duplication facilities and millions of copies shipped. VHS was also prone to degrading quality over time through head wear, so the compromise made sense, but we got some grief for the new strategy from both the press and home theater enthusiasts.

So, Brian, yes you're basically correct because the approved master that was used for the LD was almost certainly the one to be used on the VHS edition of the same title.
Any idea why they abandoned all of this when Creative and now Razer took over? I know the Cinemark partnership. But even blu ray discs. I can count the titles that have THX involved, and they aren’t even involved in 4K. It’s like they want the Lucasfilm legacy, but that’s it. Make that name mean something again. Maybe I’m nostalgic for the 90s too much, but when you saw the logo, and heard Deep Note, it meant something.
 
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My old Kenwood VR-8070 was THX "Select". I still have it. I suppose that was a label for lower priced receivers back then. I always enjoyed the old THX intro to some of my DVD's.
THX Select was a way to get receivers and speakers to lower price points by promoting the same performance in rooms up to 1500 cu ft, while THX Ultra branding was for equipment in rooms for 3000 cu ft.
 

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Any idea why they abandoned all of this when Creative and now Razer took over? I know the Cinemark partnership. But even blu ray discs. I can count the titles that have THX involved, and they aren’t even involved in 4K. It’s like they want the Lucasfilm legacy, but that’s it. Make that name mean something again. Maybe I’m nostalgic for the 90s too much, but when you saw the logo, and heard Deep Note, it meant something.
I don't really know, Brian. To me it's all a bit sad. They should have led the charge on PLF auditoriums and 4K home media as you say - they had (and have) all the know-how.

The company got obsessed with car and computer audio in the early 2000s when Creative took over which I think diluted the brand and muddied up the messaging. Their core expertise was pro and home cinema. Should have stayed that way IMO - there's still a need for such an organization.
 
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We had a store called Ultimate Electronics, maybe you’ve heard of them. One of my high school buddies would always go to that store and inside their theater room configure the speaker set up and fine tune all the equipment like it was his own just to play the THX intro.
He’d drag us down there, sit us down in the theater and play THX intro over and over LOL!!
 

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I don't really know, Brian. To me it's all a bit sad. They should have led the charge on PLF auditoriums and 4K home media as you say - they had (and have) all the know-how.

The company got obsessed with car and computer audio in the early 2000s when Creative took over which I think diluted the brand and muddied up the messaging. Their core expertise was pro and home cinema. Should have stayed that way IMO - there's still a need for such an organization.
Since Disney now owns Lucasfilm, maybe petition Disney to buy THX from Razer and get it back in the family and have the name mean something again. I believe you told me that a lot of the people who are involved with Dolby Cinema, worked for THX at the time. At least that work is still out there, just not called THX.
 
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andySu

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I have my THX pin somewhere in a kitchen draw?

THX pin.jpg


THX poster 1.jpg

Got the Lucasfilm Ltd THX sound system. The Audience Is Listening. ultra cheap!

THX JBL.jpg

THX sound system.jpg

Lucasfilm Ltd THX 3417 crossover monitor in the bottom of my amplifier rack.

THX cards.jpg

Lucasfilm Ltd THX crossover cards, that usually leased to THX cinemas often remain intact. You can get THX 3417 cheap on ebay.

THX rear back.jpg


THX manual.jpg


THX cineams.jpg

Came across this in boxOffice magazine. Is that England on the map. Empire Leicester Square and High Wycombe. Never heard the one at the original Warner West End, sure it would have knocked my socks off.
 
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andySu

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I can agree and disagree, but would agree UCI Wycombe 6, #1 THX was soundly, out of this world.
I saw Indiana Jones 3 at local MGM screen #1, Bournemouth in 70mm at least 3 times before I saw it at Empire #1 and I can hear feel the difference was powerful at Empire #1.

I saw Arachnophobia at odeon #2 Bournemouth December 1989, and I enjoyed it. A friend and I went up Wycombe 6, January 1990, and there playing was Arachnophobia in Dolby SR THX sound system. We arrived 15mins late show had started so we waited for next show. I stepped in and stood at the back of the auditorium, WOW oh my! It was pressing against my feet. legs waist, chest arms, face, the whole body. Awesome! And that was the softest scene in the movie the jungle scene where they find a "new kind of spider". The music bass notes was pressing against my body!

We sat about 5 rows from the front, centre line. When THX Broadway started I could feel it pressing against my body, the instant it started, never mind about 18 sec into it when dynamics build up high. The first few seconds was impressive, with that JBL THX set-up.

The spider attack scene in the wine cellar with Trevor Jones, score was pressing against my body and even noticing some of the bass on stage left sort of had an up/down movement when the spider was crawling along the guys leg. The notes bass was just incredible for Dolby Stereo SR in JBL THX. They seemed to growl grunt with out of space, expanding universe bass sub bass.
 

Brian Husar

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I have my THX pin somewhere in a kitchen draw?

View attachment 68270

View attachment 68271
Got the Lucasfilm Ltd THX sound system. The Audience Is Listening. ultra cheap!

View attachment 68272
View attachment 68274
Lucasfilm Ltd THX 3417 crossover monitor in the bottom of my amplifier rack.

View attachment 68275
Lucasfilm Ltd THX crossover cards, that usually leased to THX cinemas often remain intact. You can get THX 3417 cheap on ebay.

View attachment 68276

View attachment 68277

View attachment 68278
Came across this in boxOffice magazine. Is that England on the map. Empire Leicester Square and High Wycombe. Never heard the one at the original Warner West End, sure it would have knocked my socks off.
Wow. Just now seeing this. I want some of those posters. This is awesome.
 
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Mike Wadkins

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I have my THX pin somewhere in a kitchen draw?

View attachment 68270

View attachment 68271
Got the Lucasfilm Ltd THX sound system. The Audience Is Listening. ultra cheap!

View attachment 68272
View attachment 68274
Lucasfilm Ltd THX 3417 crossover monitor in the bottom of my amplifier rack.

View attachment 68275
Lucasfilm Ltd THX crossover cards, that usually leased to THX cinemas often remain intact. You can get THX 3417 cheap on ebay.

View attachment 68276

View attachment 68277

View attachment 68278
Came across this in boxOffice magazine. Is that England on the map. Empire Leicester Square and High Wycombe. Never heard the one at the original Warner West End, sure it would have knocked my socks off.
West end was decent, but nothing amazing.
 

zoetmb

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West end was decent, but nothing amazing.
That was one of the problems with THX. In spite of the certification, there was still great differences between cinemas that were certified.

For example, in NYC, screens 6 and 7 at the Chelsea Cinema 9, a screen at the Encore Worldwide 6 and a screen at the Loews Orpheum VII were all THX certified, but they didn't sound anywhere near as good as the Coronet in San Francisco or the National and Village in Westwood.

The other problem with THX was that while it was well marketed on the West Coast, it was very poorly marketed in NYC (and I would assume some other places). The theaters in NYC never advertised they had THX screens and you couldn't tell from newspaper listings which screen was THX.
 

crowe-t

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I saw a movie at one of the THX theaters in NYC years ago and they didn't play the THX trailer before the movie. I agree it wasn't marketed all that much in NYC.