The Home Theater Connection



	Ask The Installer with John Chance of The Home Theater ConnectionAdvice on home theater, audio, and video (originally printed in Oct. 2006 edition of Sound & Vision Magazine) Q. I’m moving into a new home, and the den that will house my home theater is 24 x 18 feet. What can I do myself to treat the room acoustically? There’s a fireplace on one of the short walls, and our 60-inch rear-projection HDTV will go on the other. The long walls have a sliding glass door on one side and a picture window opposite that. The room has hardwood floors, but we’re starting from scratch with furnishings and floor/window coverings, and would consider carpeting or a large area rug. Paul Ackerman / via email A. JOHN CHANCE, Owner, The Home Theater Connection, Staten Island, NY, says: Given your dimensions and layout, a key goal will be keeping the room from sounding too “live.” First, consider heavy drapery on the sliding glass door and the picture window. This will help absorb some of the sound and also allow you to control ambient light during the day — something to consider with a rear- projection HDTV. (For convenience, think about motorized drapes, or at least pre-wiring for such). Wall-to-wall carpeting would be a good choice for the floor; however, if you’re intent on keeping the hardwood, a large area rug or two would help acoustically in the same way. Furniture also plays a big role in acoustic design; you may want to consider large, overstuffed couches for additional absorption. Speaker design and placement, and the resulting reflection points, are important, too. Horn- driven speakers, for example, have a narrower dispersion than conventional speakers, which might be desirable depending on how far back your listening position will be. Strategically placed acoustical panels can also help greatly in tailoring the sound of the room. These recommendations will help with absorption. However, if you hope to play movies loud without disturbing the rest of the house, sound isolation may be your toughest challenge. Kineticsnoise.com is a great place to learn more about absorption and isolation techniques and products.	thetechzone - Q&A Ian G. Masters & Al Griffin Techs & Specs Q. I have a technician coming to my house for regular maintenance on my Sony LCD rear-projection TV. Should I have him tweak any settings while he’s here? I know in your Test Bench for TVs you frequently tweak the color temperature and grayscale tracking, so I was hoping you could give me some settings for the tech to work on. Ramon Aranda / Union city, CA A. A.G. says: The specs that TVs get tweaked to in the factory are rubber-stamped and documented by the company’s engineers, so any maintenance visit you receive from a service technician will likely result in them checking that the settings meet those specs. (The tech may also get confused when you ask about grayscale adjustments, since that doesn’t come under the category of regular TV maintenance.) To get your TV properly adjusted to the 6,500°K grayscale specification, a better bet is to contact a technician trained by the Imaging Science Foundation (visit imagingscience.com/isf-trained.cfm to find one in your area). You can also perform basic tweaks yourself by using one of the test DVDs out there. By the way, I’m not sure what kind of service plan you signed up for, but most TVs don’t require a “regular maintenance” visit. What Watts? Q. A few years ago, I purchased a home theater receiver rated at 100 watts per channel into 6 ohms. The FTC standard for amplifiers now rates receivers at 8 ohms per channel. I’m considering upgrading and want to know how many watts I should look for so each speaker produces more volume. For comparison, how many watts would each channel of my 6-ohm receiver be producing if it were rated into 8 ohms? JOE OBERUC / OGDEN, UT A. I.A.M. says: Your existing 100-watt receiver would produce less power per channel into an 8-ohm load, but the differences are very small. It would probably put out about 70 watts for the same level of distortion, but this is only a couple of decibels down in volume, and the audible difference would be just barely noticeable at best. But, if your goal is simply to get your new system to play louder, these wattage numbers have little bearing. What determines perceived loudness is the average level of the signal, and that’s likely to be only a very few watts at any given moment — often 10 watts or less. The power rating (that 100- or 70-watt number) says more about your amp’s ability to handle momentary transients with minimal distortion. So if you want to play louder, simply turn up the level. You’ll have a bit less “headroom” for those transient peaks, but you’re unlikely to hear that. You could indeed buy a more powerful amplifier, but it would have to be twice as powerful to make a significant difference. Resolution Recommendation Q. I’m planning to buy a moderately priced HDTV — either a 50-inch plasma, or a front projector with a 60-inch-wide screen. I’ve been looking at 720p-resolution sets, but am wondering if it would be wise to wait for a 1080p model. Which would give me the sharper 1080p picture from a 6- to 7-foot viewing distance: the 50-inch plasma or the front projector? Also, would the difference in resolution over a 720p set be substantial? RONALD V. TANCREDI / FARMINGDALE, NY A. A.G. says: Assuming that both the 50-inch plasma and the front projector have native 1080p resolution, they should look equally sharp at a 6-foot viewing distance. But at 7 feet, you’ll get into a gray area where your eyes’ ability to process that level of detail will begin to falter. So the answer to your first question depends on how close you plan to sit. If it’s 6 feet away from the screen, you can safely go with the plasma. But if it’s 7 feet, I’d choose the front projector and 60-inch screen option. As for your second question: The difference between 720p- and 1080p-resolution TV isn’t substantial, but it’s definitely noticeable provided you sit close enough to the screen to appreciate it. Degraded Satellite Q. When my digital satellite dish was installed several years ago, the dealer said not to run it through a VCR because it degrades the picture. Would a DVD recorder have the same effect? GLENN WAGGONER / RIDLEY PARK, PA A. I.A.M. says: In general, the fewer the devices a signal passes through, the better. If all you’re talking about is running the composite- video output of your satellite receiver through your DVD recorder or VCR on its way to the TV, you probably won’t notice much difference, and the convenience of simply being able to hit the “Record” button at short notice might outweigh everything else. Still, it’s worth checking it both ways. On the other hand, your satellite-to-TV signal should be something more advanced — at least S-video, if not component video — in which case a direct-to-TV connection will preserve the signal quality best. High-Def Tests Q. With the introduction of HD DVD and now Blu-ray players to the market, will there be home theater calibration discs in either format for calibrating TVs to ATSC digital television standards? SCOTT MESSBARGER / WESTERVILLE, OH A. A.G. says: An HD DVD version of video expert Joe Kane’s Digital Video Essentials test disc is in the works, scheduled for release sometime this fall. No such news yet for Blu-ray, but here’s an Easter egg for ya if you’re waiting: A suite of test patterns embedded in Sony’s Blu-ray releases can be accessed by pressing 7669 (the numerical equivalent of SONY) on the player’s remote control, followed by the Enter key. Pause Cause? Q. I have a couple of DVD players that delay for about a half-second during the middle of a movie. Both players are 2 years old or less. What causes this problem, and what can I do to prevent it? WAYNE CRITH / TOPEKA, KS A. A.G. says: The problem you cite isn’t a defect; it’s caused by the player’s laser mechanism refocusing to read the second data layer on a dual-layer disc. The length of a layer-change pause varies from player to player and disc to disc. Unfortunately, you can’t prevent it, short of finding another player with a less pronounced pause.