Sound Advice: Subwoofers can be placed near plasma TV

  • Article by: DON LINDICH
  • Special to the Star Tribune
  • August 12, 2011 - 2:13 PM

Q I recently purchased Panasonic's ST30 3-D plasma TV, which you have recommended in the past. Can we put our two subwoofers under our new TV? My husband said he read you can't do that because it will distort the picture. Is that true? Also, do you have recommendations on which 3-D glasses to buy?

A The reason your husband is concerned about picture distortion is because older tube TVs could indeed have their picture distorted from the magnets contained in speakers. This led to shielded speakers becoming the industry norm, so they could be placed anywhere without fear of picture distortion.

In your case, it is a moot point because plasma TVs, as well as LCDs, are immune to distortion from magnetic fields. If you want to put the subwoofers beneath a stand or under a wall-mounted TV, you should be fine.

If you are suggesting using the two subwoofers as a TV stand, it's a bad idea. Vibrations from the subs will be transferred to your TV and possibly affect its lifespan and reliability. 

When the TV enters 3-D mode, several changes take place. Most important, alternating frames are displayed many times per second. The active shutters in the glasses sync with the TV so the proper images are received by each eye, creating the 3-D effect.

The picture changes, too. It takes on a slight change in color tint, and the image is slightly brighter. The lenses in the glasses are designed to match perfectly with the altered images, adding a corrective tint and just enough density (darkening) to create a proper image. If you set your TV to 3-D mode without putting on your glasses, you will easily see the difference in color and brightness.

For these reasons, if you want to be sure of 100 percent reliability, compatibility and accuracy, you should buy the glasses from your television's manufacturer. No company knows a product better than its maker, and you can be confident that its glasses will do a perfect job with no errors in synchronization, color or brightness.

That said, 3-D glasses have become available from third parties, and they can be attractively priced. If you need extra sets for occasional use, they might be acceptable. If you have a set of glasses from the TV manufacturer, you can easily compare them to see if you are making image-quality sacrifices. For that reason, don't buy more than one set of third-party glasses when starting out.

Consumer confusion over issues such as glasses probably has affected 3-D adoption, and manufacturers have taken notice. Recently an agreement was made between Panasonic, Samsung and Sony to develop a standard for 3-D glasses that will make them compatible across brands. Those glasses will be available in 2012, likely leading to lower prices and more choices.

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