Q I recently purchased an LG 47-inch LED-LCD HDTV. I connected it to my wireless network and viewed Netflix and other streaming services. At the store, the picture looked amazing, but at home it is not nearly as sharp and colorful. What's wrong?

A The problem isn't with your television or picture settings, but with the signal. High-definition television streamed over the Internet doesn't approach the picture quality of other HDTV signal sources such as over-the-air broadcast, cable, satellite or Blu-ray. The store certainly has a high-quality signal, as well as top-quality program material handpicked to make the televisions look their best.

About a year ago I posted a review of Netflix streaming on my website. While I was disappointed by the picture quality, I liked the convenience of having such a large library of movies and TV shows at your fingertips, especially since streaming is free with a regular Netflix membership.

I purchased a Panasonic ST30 plasma and connected it to my wireless network. I was pleased to find Netflix's high-def picture quality much improved from before. Unfortunately, the sound quality still rates low. But it's nice to have for watching old TV shows.

If you don't have cable or satellite service, connect a small antenna to your TV. Go into the setup menus and set the antenna to "Air," run the auto-program and the TV will load all the stations it can detect. You will find the picture quality from a local HDTV broadcast to be a dramatic improvement over Web sources.

I have not tested your TV, but using a mode such as "Standard," "Custom," or "Movie" along with a color temperature set at "warm" is a good start for any TV.

More on loud TV ads

Thanks to Cas Gromadzki of the Villages, Fla., for this e-mail about why TV commercials are so loud:

"In 1998 when I lived in Jackson Heights, N.Y., an article appeared in the newspaper's local news section," he wrote. "Recently, the New York City water department had noticed that water pressure was dropping dangerously low in the evening hours, at regular intervals. After a few weeks of monitoring the situation, they determined that TV viewers were going to the bathroom in huge numbers during TV commercials, and the water pressure drop was not a problem as it lasted about 5 minutes each time a commercial aired.

"Obviously the article was also noticed by the TV stations, and within weeks the era of very loud commercials began. The broadcasters still deny they make commercials louder than other parts of their TV broadcasts, but it is clear the volume is greatly increased so the commercial will still be heard while the person is away in the bathroom."

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