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Showing posts with label surround sound. Show all posts
Showing posts with label surround sound. Show all posts

Thursday, June 28, 2007

We Want Surround Sound, Not Unwieldy Wires! How Can I Easily Integrate Rear Channel Speakers?

One of the benefits of moving toward a home entertainment setup with HDTV is the delivery of surround sound from HD sources. The experience of a movie from a Blu-ray or HD DVD player can be greatly enhanced by audio cues that literally surround you and immerse you in the picture. To take advantage of this, however, you need to have multiple speakers scattered throughout the room with wires going through walls, under rugs, or over ceilings. Or that's what one would think. There are actually some options out there to help achieve home theater surround sound without all of the wired speaker trouble.

One of the most popular methods of obtaining surround sound involves a setup of six speakers, called "5.1 surround sound". This translates into a left, center, and right channel speakers as well as two rear speakers. The "dot one" after the five refers to the sub-woofer that delivers the deep bass rumbles. Since components such as the TV, receiver, and DVD player typically sit at the front of the room, integrating the left, center, and right channel speakers is usually not a problem. There are some "three in one" speakers that combine these, but the help is really needed in finding how to hook up those rear channel speakers. This is the achilles heel of surround sound setup. For many, the idea of running wires through the room ranges from unpleasant to infeasible. There are two main alternatives to traditional rear speaker wiring: wireless speakers and sound projectors.

Wirless Rear Speakers
The idea of running all of the surround sound speakers wirelessly is not a new concept. But the idea has been plagued by issues of throughput capabilities, range, and interference. Though the use of radio frequency signals that focus on just two speakers (our rear channels), the concept of wireless becomes more practical. There are two ways to accomplish this. The first is done by using a wireless speaker module (like the one shown from Kenwood), that may utilize the speakers you already have. The second method includes a set of speakers, such as the ones shown by Acoustic Research. Both use a base unit that attaches directly to the audio source and generally have ranges over 100 feet. Because they use radio frequency, the signal is not interrupted by walls or furniture. The thing to keep in mind with a wireless speaker system is that power needs to be delivered to those rear channel units. Although some wireless speakers may be run with batteries, it is recommended that they be plugged into a nearby outlet. In most homes, however, a power outlet is easier to find than a good place to run those wires.



Sound Projectors
A second alternative for those wishing to escape the mess of speaker wires utilizes a method of sound projection and reflection. A single sound source uses a large number of speakers to bounce sound off available walls and reflect back to the listener. This provides the audible illusion of speakers scattered throughout the room. Yamaha makes some of the most popular devices of this type. They claim that they can deliver multi-channel sound to the listener in the same way that sound from front, center and rear speakers does. The sound projector precisely controls the orientation of sound by focusing it into beams. The center channel sound is heard directly, while the sounds from other channels are heard after reflecting off the walls surrounding the listener. Depending on the room configuration, this is done through a variety of beam modes. An example of these beam modes is shown in the illustration provided.

Although some woofers are included in the package, to deliver deep bass sounds, the manufacturer recommends the use of this product along with a sub-woofer. The sub-woofer may be the only other audio component needed. Due to the unique way it refects audio, the sound projector replaces all of the other speakers, including the rear channels. And because the device decodes Dolby Digital, DTS, Pro Logic, and Pro Logic II, it effectively replaces what a receiver does. It includes a variety of audio inputs, including digital and analog, allowing multiple devices to be attached directly to the speaker device and bypassing any receiver.



So, how good is the audio experience from a sound projector? Well, it depends. The verdict is that the audio quality is much more dependent on the room configuration than a standard speaker setup. If there are good walls that can reflect sound, however, then sitting in the "sweet spot" can have breathtaking results. If the room configuration does not allow proper beam bouncing, the quality of the experience may deteriorate. For many cases, however, it does a good job of providing surround sound experience without a big hassle. For those audio enthusiasts, it will likely not replace actually having multiple speakers in the room. But for those who value convenience over perfection, it is a great alternative. Additionally, it is nice way to get surround sound in secondary rooms such as a bedroom.

Conclusion
For those avoiding the leap to a surround sound system because of the difficulty in integrating rear channel speakers, help is available. Solutions involving wireless speakers or sound projectors can facilitate the installation and avoid the hassle of rear speaker wires. So come and join the fun - and immerse yourself in the surround sound experience!

Monday, June 4, 2007

HD Ignorance Is Not Bliss! What Are Ten Things I Should Know About HDTV?

I have written many HDTV posts but have failed to provide an overview of oft misunderstood terms and high-definition subjects. In order to help shed light on these concepts, here are ten things that everyone should know about HDTV:

  1. There are three major benefits that the HDTV format brings. Besides a lighter wallet and a slight headache, your HDTV setup should give you these main features: First, you’ll experience high resolution that provides great picture detail. The screen and content will have at least 720 lines of resolution. This is superior to standard or enhanced definition (DVD quality), which only has 480 lines of resolution. Second, you’ll have a widescreen format similar to a theater experience. HDTV content is presented in a 16:9 aspect ratio. This is wider than your older, boxier televisions. Lastly, HDTV uses 5.1 surround sound output. The sound content will be divided among five speakers plus a sub-woofer. These speakers include the left, center, and right channel as well as two addtional speakers at the back of the room.

  2. Not all flat panels are HDTVs and not all HDTVs are flat panels. If you're a little confused by that statement, keep in mind that two wrongs don't make a right, but three lefts do. Flat panel televisions are those ultra-thin televisions that are typically no thicker than four inches. The plasma and LCD technologies currently dominate the flat panel market. While most flat panels are high definition, there are still some available as an inferior enhanced definition television (EDTV). Additionally, there are many HDTVs that are not flat panels. Microdisplays are not as thin as flat panels but at 10” to 18” in depth, they are much shallower than the old picture tubes. These microdisplays include DLPs, LCD Projections, and LCoS televisions. For more information on these HDTV types, read High Def Alphabet Soup.

  3. Not all features are created equal, so be careful when comparing. Michael Jordan and I both have vertical leaps of 42 (inches for Jordan and centimenters for me). That comparison is similar to ones made on HDTVs. First, not all HD is the same. There are three popular high definition resolutions, all improvements over the 480-line enhanced definition resolution that DVDs provide. The 720p resolution is a progressive scan that renews all of its 720 lines each refresh. The 1080i resolution, similar in quality to 720p, uses an older interlaced scan that refreshes only half of its 1080 lines at a time. The 1080p resolution (also called Full HD) has a superior 1080-line progressive scan resolution that delivers more than twice the number of pixels as 720p. Due to its enhanced resolution, 1080p Full HD commands a premium price tag in the retail marketplace. Additionally, be careful when reading manufacturer specifications on contrast ratios. A dynamic contrast ratio looks at the brightest vs. darkest points over time, but the static contrast ratio evaluates this difference at a snapshot in time. Although manufacturers may not explicitly state which ratio is being referenced, very high dynamic contrast ratios are easier to achieve than static ones. An outstanding static contrast ratio is 1,500:1, while it is not unusual to see a dynamic contrast ratio over 10,000:1. This may help you decipher misleading figures and help compare apples to apples (or PCs to PCs, for those who prefer virus infested equipment).

  4. When selecting a type of HDTV, don’t rely on old reputations. Did accusations of fuel tank explosions unfairly ruin the reputation of the Ford Pinto? Okay, so maybe that's a bad example. A better example of old reputations, however, has plagued the plasma television. Plasma was the first flat panel to hit the market and originally had issues with burn-in and longevity. Today, most high quality plasmas use techniques to avoid burn-in and have life expectancies similar to LCDs. Additionally, projection DLP televisions have had problems with “rainbows” appearing during quick movements. This problem has been addressed on newer models through the use of higher speed color wheels. Yesterday’s information can become today’s myth. Recent research is your best bet. Again, for more information on the various HDTV types and their respective advantages, refer to High Def Alphabet Soup.

  5. The pricey Full HD 1080p resolution isn’t always the best bet. When I gave a friend a coat hanger to help retrieve keys from a locked car, I cautioned him not to break a window. He told me that wouldn't be an issue because all of the windows were rolled down. Lesson: although we try to help, it sometimes just doesn't matter. A person with 20/20 vision that views a 50” television at 10 feet away will likely be unable to see a difference between 720p and 1080p. Viewing a 60” television, however, increases the size enough that a 1080p resolution will likely be distinguishable. Viewing distance and television size play an important role in determining if there is any benefit to a Full HD 1080p screen. Keep in mind that an investment in Full HD is an investment in the future. Currently there are no HD television broadcasts in 1080p so the only way to benefit from this higher resolution is through specially marked HD-DVD players, Blu-Ray players or games for the Xbox 360 or PlayStation 3. For a more detailed explanation of screen sizing considerations, as well as a lookup table for viewing distances and recommended screen resolutions, take a look at Size Matters.

  6. The type of cable connection used is important, but it doesn’t have to be costly. When I bought my car, I paid an extra $500 for helium-filled tires. Lighter weight and better fuel economy sounded like a good idea but my spare tire flew away when I let go of the string. Lesson: don't fall for helium tires - and don't fall for expensive cables. There are three good choices for HD video signals. The three-wire component video cable transfers an analog signal, while HDMI and DVI cables transfer digital signals. The only difference between the two digital cables is that HDMI also carries 6-speaker sound signals in the same single cable. While individual circumstances determine whether component or HDMI/DVI provides better picture quality (you should give each a try), HDMI/DVI are the only cables to support Full HD 1080p resolution. Additionally, the analog component cabling is susceptible to signal quality deterioration due to quality of the cable, length of the run, or splitting. For the digital cables, however, The TV either receives the signal or it does not. Any qualified HDMI/DVI cable will provide optimal, lossless picture quality, regardless of price. There is no need spend a lot here, especially if you have moderate runs of cable.

  7. Placing an HDTV in your home does not mean that everything you watch will have crystal clear detail. HDTV has tremendous capabilities, but it can't provide a quality picture from a poor source any more than a Porsche can perform with water in its fuel tank. Due to the increased size and pixel count of most HDTVs, a standard definition signal will look poor and all imperfections will become very visible. To get an HD signal from your satellite or cable provider you need to subscribe to their HD service. Keep in mind that not all channels will be in HD and those HD channels may not play HD programs all of the time. Depending on your location, you can also get local channels in HD over-the-air (i.e. from an antenna). Although standard DVDs are not in HD, they can look pretty darn good using an upconverting DVD player that translates the image to near-HD. The HD-DVD and Blu-Ray players, however, are your best bet for true HD movies on disc. For gaming, the Xbox 360 and Playstation 3 have HD output, but Nintendo’s Wii does not. Remember that component, HDMI, or DVI cables are needed to carry that HD signal (you won’t get it from a composite or s-video cable) and HDMI and DVI are required for 1080p. Without an HD source or HD cabling, you're just putting water in the fuel tank. For more, read Hi Def Jam.

  8. A widescreen television will not eliminate all black bars. Although this is what I have termed a "pain in the aspect," it's important to understand why black bars appear. The aspect ratio of HDTV is 16:9, which means that for every 16 units wide, the screen is 9 units high. If you have an HD programming source (i.e. satellite, cable, or over-the-air), the HD programs will fit perfectly on your new HDTV display. Most television programming, however, is still in standard definition and the boxier 4:3 aspect ratio. This will give black bars at the side. Additionally, movies are typically shot using wider 1.85:1 or 2.35:1 theatrical aspect ratios. These movies will have black bars at the top and bottom of an HDTV. Zooming or stretching the image can eliminate the black bars, but you should be aware of the mismatch in aspect ratios and distorted images. Visit my earlier post, Pain in the Aspect, for more detail on the subject.

  9. Surround sound is part of the HDTV package. Most ladies won't purchase a new dress without new pumps to complete the package. The same accessorizing should be done when creating your high definition home entertainment system. Don’t forget to include an audio receiver capable of 5.1 surround sound output that comes with HDTV. Most HDTV sources will send sound output to five speakers plus a sub-woofer (for deep base sounds). The HDMI cable connectivity not only passes an HD video signal, but a 5.1 surround sound signal, too. All of this is contained in the single cable, making it the connection method of choice. Using an HDMI cable to connect an HD cable/satellite box to an audio receiver and then to your HDTV will likely bring superior video and sound to your television viewing experience. It also allows the receiver to facilitate video switching between many sources (cable, satellite, video games, over-the-air, DVD, PC, etc.) for those TVs with limited inputs. The receiver can really be those purple pumps that complete the appearance. Look for a future post from me regarding receivers with this capability.

  10. You should place the TV as close to eye-level as possible. Ergonomically speaking, you don’t want SPS (short person syndrome), a phenomenon resulting from having to look up for extended periods of time. This means that mounting your plasma above the fireplace will likely have results similar to exhaustively comparing HDTVs: a royal pain in the neck. For most situations, the middle of your television screen should be around four feet off the floor. If you have a large viewing distance, you can get a little higher. Additionally, a projection television such as a DLP, LCD Projection, or LCoS gives its best picture when viewed from eye-level. While these projection televisions have a broad side-to-side viewing angle, their picture deteriorates quickly when viewed vertically off-center. More viewing angle information is provided in High Def Alphabet Soup.