“HOME THEATER”: FACTS AND FALLACIES
© Mark B. Anstendig
The term “home theater” is a new designation in the audio/visual world for a room with a sizeable TV/video screen and digital surround sound-reproduction. The current ideal of a home theater has a large front-projection TV system, with an image size close to that of a movie theater, and the same digital surround-sound found in high-tech movie theaters.
Trying to achieve this ideal is a grave mistake, which leads to unnecessary outlays of enormous amounts of money for 1) a too-large image size that makes all of the shortcomings of the current TV/video standard disturbingly if not unbearably visible, 2) line-doubling technology intended to make invisible the horizontal lines that make up the image, but actually degrading the sharpness and image detail and 3) digital sound reproduction that is even less capable of reproducing the expressive-emotional content of the original live sound than CDs, which are now universally known to be inadequate.1
THE CONFINING LIMITS OF IMAGE SIZE
image2 size has a built-in limitation: the TV picture is made up of
horizontal lines spaced a certain distance apart. In the
LINE DOUBLERS, THE “CURE” THAT MUDDIES THE IMAGE
the advent of movie theaters with enormous panoramic screens and
high-definition 70mm film images the public is becoming accustomed to ever
larger and more detailed images and wants them in their home viewing. This
dream is impossible until the current
In an attempt to enlarge present TV images without the disturbance of visible lines, a system called line-doubling has been devised which doubles the numbers of lines so that they remain invisible at much larger image size. But, in doing so, the sharpness and detail of the image is degraded.
In principle, a line doubler creates a duplicate of every frame of the TV image and then simultaneously transmits both images slightly displaced so that the lines from the duplicate image are exactly in between the lines of the original image. Obviously, if a machine transmits two matching images that are not precisely lined up, the sharpness and detail will be degraded. All line doublers necessarily degrade the image to some degree. And they are prohibitively expensive, with the better units costing well upwards of $10,000 and the cheapest units still costing $2,000 to $3,000. The less intricate, lower priced, units cause a lot more distortion. Expensive, more complicated units, including newly released quadruplers, perform their work with less apparent distortion, but the sharpness and resolution of detail are still noticeably “softened”, as one honest dealer described it. The irony is that, even though the lines become less apparent, the viewer still has to sit far away from the screen, or this fuzziness becomes apparent. Of course, sitting farther away results in a smaller image, unappreciably larger than that of a rear-projection set at the manufacturer’s recommended viewing distance. A better large-screen system and a top-of-the-line line doubler will provide a clean, but indistinct image for a lot of money (for purchase, installation, adjustment, and enormous upkeep costs for half-yearly expert professional maintenance, which is often not mentioned at purchase time).
THE CATCH-22 OF FRONT-PROJECTION TV
Front-projection systems consist of separate components: screen, projector, line doubler and tuner. Rear-projection TVs are exactly the same technology (separate screen, projector and tuner). But the components of rear-projection systems are permanently mounted in a box which uses mirrors or prisms to project the image the necessary distance for the screen size. Because all components are firmly fastened in their box, rear-projection TVs can be permanently adjusted at the factory and require only a simple, on-screen optical adjustment by the owner.
Not so with front-projection TVs. Their adjustments are a headache even for the highly skilled professional. All the extremely technical final factory adjustments of rear-projection sets have to be performed in the home, with the addition of extremely difficult, yet crucial operations to ensure that the projector and screen are at precisely determined distances, in precise alignment to each other, and that they can dependably remain so for appreciable periods of time. The process, which is much more difficult with free-standing components, takes a few hours (when performed by a highly experienced technician) and consists of many trial-and-error adjustments, which can easily be botched.
Our institute’s technical advisor, Mitchell A. Cotter, points out that, to be done correctly, these adjustments demand expensive test equipment and that approximately 60 fine adjustments, some of them trial and error, have to be performed in exactly the right order, or the set will not perform optimally. He also points out that expensive, half-yearly maintenance is necessary to maintain image quality, because these adjustments necessarily change over time.
EVERYONE LOOKS SICK, OR THE GREEN-CAST PROBLEM
In addition to the problems already stated, The Anstendig Institute has not, as yet, seen a front projection set that did not have some degree of green color-cast to the image. Because green is a difficult color to control in the design and manufacture of a TV set, a green cast should be looked for and avoided when buying any TV. It is the most oppressive color aberration, because, on flesh tones, a green cast makes people look sick. Less expensive sets often have this problem, but even some top-of-the-line sets suffer from it.
A SMALL SCREEN CAN HAVE A LARGE IMAGE AT CLOSER VIEWING DISTANCES
Front-projection TVs were originally developed for industrial presentations of computer images for large audiences in large rooms, where the screen size of one-piece units was not big enough and price was no object. At the larger viewing distances in such rooms, the image size for most viewers is no larger than that of a small screen TV at normal home-viewing distances. The better, more expensive projection TVs cost disproportionately more than one-piece TVs, because they are made to resolve the much higher resolution of computer images, which is not needed for TV images. (Computer monitors cost much more than ordinary TVs of the same screen size, because of their higher resolution capabilities.)
Apparent image size is directly proportional to the viewing distance. By sitting closer, a conventional tube TV can provide as large an apparent image as a front projection system. For a small group of viewers, a 60” set will be more than adequate. Because the distance at which the viewer must sit in order not to be disturbed by the lines and other distortions is considerable, the apparent image size is reduced and the potential of a front-projection set is not realized. In other words, the maximum possible image size without disturbing aberrations can be achieved with either set by varying the viewing distance. But a rear-projection set has many inherent advantages, such as a brighter picture, with more saturated colors and more contrast. It can be viewed with the lights on, can be placed anywhere in the room and moved around at will. Most front-projection systems demand a fully darkened room and have a much lower range of contrast adjustment because their highlights are not as bright nor their black tones as saturated as with tube or rear-projection sets.
DIGITAL SURROUND SOUND HAS EVEN LESS EXPRESSIVE DETAIL THAN CDs
The deficiencies of the present system of digital audio recording are a well known fact and no longer a matter of opinion.3 Yet, in order to have four tracks instead of two within essentially the same system, the manufacturers have reduced the resolving power of the digital system even further. CDs are deficient enough in expressive detail to degrade and actually change the expressive content of music. But our institute has found the sound in 4 track digital surround-sound to be irritating and unsettling as well. In our experience, it makes viewers nervous and unstill. High-quality films with excellent music, such as “Brave Heart”, “Babe”, and “Jungle Book” should keep viewers mesmerized. With these films we fidget, stop to get popcorn or use the bathroom, and listen intellectually, i.e., informationally, rather than emotionally, i.e., experientially.4
If expressive-emotional content is compromised and lost, why have filmmakers not noticed this and done something about it? The answer is that the lack of the emotion that normally holds the viewer/listener involved is noticed, albeit often without the filmmakers realizing the cause. In the last decade, there has been a nearly universal trend in filmmaking to compensate by adding more and more distracting sound-effect detail. Critics often complain about major films not being sufficiently engaging, without being able to determine the actual cause.
SONIC DISTRACTION HAS REPLACED EMOTIONAL DEPTH
The replacement of emotional depth by sonic distraction means that sound effects, instead of musical-expressive content, come at us steadily. Doors creak more loudly, chains rattle, car motors roar, feet clomp and shuffle unrealistically. Small, unimportant details are given larger-than-life sound effects. 1995 and 1996 have marked the greatest changeover to digital surround-sound, but the bulk of films most eagerly anticipated for the high quality of their talent and no-expense-spared production parameters have bombed in relation to expectations. The digital sound has sabotaged them, and, instead of emotionally engrossing speech and musical content, they are left with noisy, distracting sound tracks that quickly tire the viewer with their incessant contentless effects.
1) Avoid front-projection TVs. Their image quality does not measure up to the better tube and rear-projection sets.
2) Unless you can afford one of the best rear-projection sets, buy a 32” or 35” tube TV. Be careful of 35” sets: some are prone to interference from large speakers or other magnetically radiating sources if positioned close to the TV. Technology has improved and new 35” sets should have better picture quality and greater imperviousness to interference. The great advantage of a tube TV is that it can be viewed from any angle, while rear-projection sets have a more limited viewing angle, outside of which the image drastically loses brightness and contrast. Better sets have greatly improved the viewing angle, but there still are large differences, so this aspect should be thoroughly checked out before purchase.
3) Avoid surround-sound. Surround-sound is a silly, unnecessary sound-effect since the viewing image is necessarily in front of the viewer/listener. Even stereo can be “weird” when the speaker remains still, but the camera position changes. For example, in a group shot with a character on the left speaking, it is illogical and distracting if the sound moves to the center during a close-up and then back to the left side when the camera goes back to the whole group.
4) It is, however, desirable to have a four-speaker system, either with all speakers playing mono, or, with stereo, front and back pairs playing the respective channels. The whole body plays a role in the experience of sound, not just the ears, and sound hitting the body from all sides enhances the effect.5
5) When choosing a sound system, sound quality is most important. If money is a problem, buy a decent, basic stereophonic system, rather than a surround system for the same price. The surround-sound system has to be of lesser sonic quality, because the same price has to buy four speakers and more electronic parts. With a good program and good sound, a small-size TV will still mesmerize the viewer. But with poor sound, no TV will do so, no matter how large the image.
1 The sound-reproduction industry is already poised to release new, more accurate digital systems, after originally claiming CD technology to be perfect. One new system, High Definition CD, i.e. HDCD, has already been released. But HDCD still does not achieve a high enough sampling rate to solve the problems and equal analog sound. Perfected systems already exist and the industry is holding conferences and negotiating to determine which system should become the new standard. The original problem of a large enough storage medium to store all the additional data of a digital system with a larger sampling and bit rate has been greatly improved. But the industry seems to be making the mistake of favoring convenience by decreasing the size of the media, instead of finally bringing out a digital system with a sampling rate large enough for the sound to equal that of analog.
2 Image size is not solely the product of the size of the TV screen. Apparent image size results from the size of the image on the screen in relation to the viewing distance, i.e., a closer viewing distance means a larger image, and farther away means a smaller image.
3 See our papers “The Truth About CD and Digital”; “Digital Recordings: A Tragedy Unrivaled in the History of Art”; “Our Loss of Emotional Richness Due to Bad Sound Reproduction”; and “AB Testing: A Misapplication of Visual Criteria in Audio”.
4 See our paper “Hearing: The Informational and Experiential”.
5 See our paper “Stereo, a Misunderstanding”.
The Anstendig Institute is a non-profit research and educational institute that studies the vibrational influences in our environment, particularly those of sight and sound, and how they affect sensory perception. Its papers on sound reproduction, problems of focusing in photography, psychology of hearing and seeing, and erratic vibrational influences that affect our lives are widely distributed throughout the world. All are available free of charge.