Choose the Right Audio/Video Receiver

There is more than meets the eye when it comes to coaxing the best possible performance out of your gaming console and your audio/video system. All three of the current crop of consoles can produce incredibly sharp and detailed video and excellent surround sound, but they all do it in different ways.

The recent revolution in home theater affordability has made it possible to put together a great setup on even the most modest of budgets. Having a home theater provides a great venue for viewing DVDs and digital television at home as well as an awesome gaming experience.

Unlike the PC-gaming world, console games use the same audio formats as the movie industry. Therefore, once you’ve put together a killer audio setup for your consoles, you will have simultaneously assembled an awesome home theater. How do you choose the right equipment? First, you have to know what the equipment can and cannot do.

Understanding Audio Processing

All of the home surround-sound formats in use today have direct roots in the motion picture industry. This genealogy traces back to the ’70s when theaters equipped themselves with Dolby Labs’s emerging audio technology to play Star Wars. Due to its revelatory effect on moviegoers, George Lucas’s 1977 hit became the progenitor of a common era of movies offered in Dolby Surround Sound.

At the time of Star Wars , surround processing was in its infancy. Thanks to the digital era, surround sound has become exponentially more powerful and infinitely more immersive than the surround systems that captivated those audiences years ago. Almost more incredibly, these powerful and complex systems are available for our homes; it’s quite feasible to equal or exceed the experience of the cinema without breaking the bank.

Today’s systems take advantage of discrete audio technology. Each speaker has a specific input channel. In a typical six-channel system, movie and game producers can place sound exactly where they wish.

The brain is an amazing machine. By merely listening, you can determine distance, direction, speed, and location of an audible object, in addition to sensing the overall environment. For example, it’s possible to tell whether you are in a cathedral or inside a coffin from audio cues alone. When you combine what you hear around you with what you see onscreen, the synergistic effect is extremely powerful. Game and movie producers have become experts at providing audiences with this potent combination, but you can only achieve this with a properly set up system.

Choosing a Home A/V Receiver

The most important part of your gaming A/V system is the home theater receiver. As your rig becomes more and more elaborate, you might jockey between three or more consoles, a DVD player, and satellite or cable input, as well as any other components that you add later. A good receiver will allow you to switch between sources—provided it has the proper audio and video inputs. The receiver also decodes incoming digital surround information and powers all your speakers.

Choosing the right receiver can be tricky. Surround formats are constantly changing, to say nothing of the ever growing complexity of high-end video connections ( [Hack #41] ). That said, it is very tempting to buy a receiver based on video-switching capabilities alone, while ignoring audio properties. This can be a very expensive game to play; the biggest mistake you can make is purchasing a receiver with an underpowered amplifier.

Unlike years ago, all the channels in modern Dolby Digital home theater systems can now handle a full-range signal. This means that if your speakers are up to it, the receiver will send them a full bass signal, two or three octaves below what they might receive from an older Dolby Pro-Logic system.

Modern movies and games often tell your receiver to play full-range signals on all speakers at once. This places an unbelievable load on your amplifier. If your amp is not up to the task, it will give up, sending out a truncated signal. This type of waveform is extremely dangerous and will quickly deteriorate your speakers by forcing them to play a sharp-cornered signal that a weak amp produces. This is also called clipping . Under heavy loads, some receivers may shut down from excess heat. To help prevent this, never block the top of your receiver and be sure to give it adequate ventilation. Even if your amp never grows hot enough to shut down, you will increase its life greatly by giving it room to breathe.

Signs of quality components

The size and type of power supply is also vitally important. The power supply links your amplifier to the AC from the wall plug, so it is a limiting factor of how much power your amp can deliver to your speakers. The weight of the receiver says a lot about the quality of the power supply because it is by far the heaviest component; quality components tend to weigh more than their cheaper counterparts.

If you can afford it, buy a toroidal power supply. This type of construction provides higher efficiency, greater power delivery, and cooler operation. It also provides much more juice than a standard rectangular “EI core” supply. You can recognize a toroidal power supply by its doughnut-shaped core. EI core supplies are square.

Check that your prospective purchase has a glass-epoxy main circuit board. You can tell a glass-epoxy board by its green color. Brown boards are made of pressed paper and are very susceptible to solder joint failure due to expansion and contraction as the board heats and cools. Glass-epoxy boards are much more durable and withstand extreme heat without deforming. A receiver with a glass-epoxy board will last longer; this is generally a hallmark of quality construction found on higher-end receivers.

Another indication of a quality rig is a five-way binding post for connecting speaker wires. This is a large knurled knob that allows you to connect spade lugs, banana connectors, and even bare wires. This is the best kind of terminal to have because it is very versatile; it’s often present on high-quality speakers. Spring tab terminals are the worst because they offer a tiny connection surface area and no alternative to the very small pin-connectors only they support. Worse still, it takes very little movement to knock pin connectors out of the terminal because the small springs that hold them in place weaken over time. Avoid receivers with spring tab terminals; they often have poorly conceived overall designs.

Audio power consideration

One of the lesser-known evils in home theater amplifiers is dynamic compression, i.e., when your equipment electronically limits the maximum output of the amplifier. You’ll often find this in the convenient and inexpensive home-theater-in-a-box (HTIB) systems. Since the manufacturer sells you a receiver and speakers in a single package, they know precisely the limitations of the system, which allows them to cap the volume at a set point. While this prevents your speakers from clipping, preserving their health and longevity, this seriously limits the capability of a system to play at a realistic volume for many rooms. This is the biggest drawback of the HTIB system. Always test a prospective purchase and listen for punchiness in the bass and clarity in the dialogue during a loud scene. Weak amps will show their true colors here, and you will find it hard to understand what is going on in busy, loud sequences.

A powerful amplifier will grab your speakers and tell them what to do. It is always better to have too much power than too little. Speakers often have power ratings and general recommendations for amplifier strength, though they usually focus more on the minimum end of the scale. If your amplifier is much more powerful than the recommended rating on your speaker, don’t worry; it will provide your speakers with a nice clean signal at all times. Obviously, there are limits, but you will wreck 100 speakers with too little power before you break one with too much.

Audio/video switching

Finally, you may not have to use an A/V receiver for audio and video switching. Modern televisions, especially HDTV models, have abundant audio and video inputs that allow you to switch between multiple sources using the television itself.

You can still send the audio signal to a home A/V receiver via the audio output jacks. Many TVs have two sets of audio out jacks: one fixed-volume and one variable. The fixed-volume jacks work for using an amplifier or receiver and using the volume control on those instead. This is a great way to use an older receiver whose only limitation is a lack of video inputs. The receiver controls the volume of the sources. Look for a menu function that disables the TV’s speakers.

The variable outputs work best when you have an amplifier with no volume control; the TV’s volume control will control the overall volume of the system. You can also use the variable output with an A/V receiver, but having two volume controls is confusing and will likely degrade your signal. Your A/V receiver most likely has a better-quality volume control anyway, so it’s better to use it with the variable output on the TV.

Please bear in mind that using the TV as a switching device can quickly lead to a confusing and difficult-to-operate system. Most televisions don’t have digital audio inputs, so if you want the benefits of digital audio, you have to send video signals to the TV and audio signals to the A/V receiver. Once the two signals go their separate ways, make two input changes when you change sources: one video input selection on the TV and another on the receiver. Using an A/V receiver that switches both at once will be more convenient for you, but, more importantly, for your family and friends.

One hallmark of a great system is when someone besides the owner can operate the system easily. A properly set up A/V receiver will help you achieve that goal.

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