Wednesday, March 7, 2007

Consumer Reports - Receivers

The receiver is the brain of an audio/video system. It provides AM and FM tuners, amplifiers, surround sound, and switching capabilities. It’s also the heart of the setup--most of the devices in a home-entertainment system connect to it, including audio components such as speakers, a CD player, cassette deck, and turntable, as well as video sources such as a TV, DVD player, VCR, and cable and satellite boxes. Even as receivers take on a bigger role in home entertainment, they’re losing some audio-related features that were common years back, such as tape monitors and phono inputs. Manufacturers say they must eliminate those less-used features to make room for others.

WHAT'S AVAILABLE

Sony is by far the biggest-selling brand. Other top-selling brands include Denon, JVC, Kenwood, Onkyo, Panasonic, Pioneer, RCA, and Yamaha. Most models now are digital, designed for the six-channel surround-sound formats encoded in most DVDs and some TV fare, such as high-definition (HD) programming. Here are the types you’ll see, from least to most expensive:

Stereo. Basic receivers accept the analog stereo signals from a tape deck, CD player, or turntable. They provide two channels that power a pair of stereo speakers. For a simple music setup, add a DVD or CD player to play CDs, or a cassette deck for tapes. For rudimentary home theater, add a TV and DVD player or VCR. Power typically runs 50 to 100 watts per channel.

Price range: $125 to $250.

Dolby Pro Logic. Dolby Pro Logic, Pro Logic II, and Pro Logic IIx are the analog home-theater surround-sound standard. Receivers that support it can take a Dolby-encoded two-channel stereo source from your TV, DVD player, or hi-fi VCR and output them to four to six speakers--three in front, and one to three in back. Power for Dolby Pro Logic models is typically 60 to 150 watts per channel.

Price range: $150 to $300 or more.

Dolby Digital. Currently the prevailing digital surround-sound standard, a Dolby Digital 5.1 receiver has a built-in decoder for six-channel audio capability--front left and right, front center, two rear with discrete wide-band signals, and a powered subwoofer for low-frequency, or bass, effects (that’s where the “.1” comes in). Dolby Digital is the sound format for most DVDs, HDTV, digital cable TV, and some satellite-TV broadcast systems. Newer versions of Dolby Digital, 6.1 and 7.1, add one or two back surround channels for a total of seven-channel and eight-channel sound, respectively. To take advantage of true surround-sound capability, you’ll need speakers that do a good job of reproducing full-spectrum sound. Receivers with digital decoding capability can also accept a signal that has been digitized, or sampled, at a given rate per second and converted to digital form. Dolby Digital is backward-compatible and supports earlier versions of Dolby such as Pro Logic. Power for Dolby Digital receivers is typically 75 to 150 watts per channel.

Price range: $200 to $500 or more.

DTS. A rival to Dolby Digital 5.1, Digital Theater Systems also offers six channels. It’s a less common form of digital surround sound that is used in some movie tracks. Both DTS and Dolby Digital are often found on the same receivers. Power for DTS models is typically 75 to 150 watts per channel.

Price range: $200 to $500 or more.

THX-certified. The high-end receivers that meet this quality standard include full support for Dolby Pro Logic, Dolby Digital, and DTS. THX Select is the standard for components designed for small and average-sized rooms; THX Ultra is for larger rooms. Power for THX models is typically 100 to 170 watts per channel.

Price range: $500 to $2,500 and up.

IMPORTANT FEATURES

Controls should be easy to use. Look for a front panel with displays and controls clearly labeled and grouped by function. Onscreen display lets you control the receiver via a TV screen, a squint-free alternative to using the receiver’s tiny LED or LCD display. Switched AC outlets (expect one or two) let you plug in other components and turn the whole system on and off with one button.

Remote controls are most useful when they have clear labels and buttons that light up for use in dim rooms. It’s best if the buttons have different shapes and are color-coded and grouped by function--a goal seldom achieved in receiver remotes. A learning remote can receive programming data for other devices via their remotes’ infrared signal; on some remotes, the necessary codes for other manufacturers’ devices are built-in.

Input/output jacks matter more on a receiver than on any other component of your home theater. Clear labeling, color-coding, and logical groupings of the many jacks on the rear panel can help avert glitches during setup such as reversed speaker polarities and mixed-up inputs and outputs. Input jacks situated on the front panel make for easy connections to camcorders, video games, MP3 players, digital cameras, MiniDisc players, and PDAs.

A stereo receiver will give you a few audio inputs and no video jacks. Digital-ready receivers with Dolby Pro Logic will have several types of video inputs, including composite and S-video and sometimes component-video. S-video and component-video jacks allow you to route signals from DVD players and other high-quality video sources through the receiver to the TV. Digital-ready receivers also have analog 5.1 audio inputs. These accept input from a DVD player with its own built-in Dolby Digital decoder, an outboard decoder, or other components with multichannel analog signals, such as a DVD-Audio or SACD player. This enables the receiver to convey up to six channels of sound or music to your speakers. Dolby Digital and DTS receivers have the most complete array of audio and video inputs, often with several of a given type to accommodate multiple components.

Tone controls adjust bass and treble, allowing you to correct room acoustics and satisfy your personal preferences. A graphic equalizer breaks the sound spectrum into three or more sections, giving you slightly more control over the full audio spectrum. Instead of tone controls, some receivers come with tone presets such as Jazz, Classical, or Rock, each accentuating a different frequency pattern; often you can craft your own styles.

DSP (digital signal processor) modes use a computer chip to duplicate the sound characteristics of a concert hall and other listening environments. A bass-boost switch amplifies the deepest sounds, and midnight mode reduces loud sounds and amplifies quiet ones in music or soundtracks.

Sometimes called “one touch,” a settings memory lets you store settings for each source to minimize differences in volume, tone, and other settings when switching between sources. A similar feature, loudness memory, is limited to volume settings alone.

Tape monitor lets you either listen to one source as you record a second on a tape deck or listen to the recording as it’s being made. Automatic radio tuning includes such features as seek (automatic searching for the next in-range station) and 20 to 40 presets to call up your favorite stations.

To catch stations too weak for the seek mode, most receivers also have a manual stepping knob or buttons, best in one-channel increments. But most models creep in half- or quarter-steps, meaning unnecessary button tapping to find the frequency you want. Direct tuning of frequencies lets you tune a radio station by entering its frequency on a keypad.

HOW TO CHOOSE

First, don’t assume that pricey brands outperform less costly ones. We’ve found fine performers at all prices. Points to consider:

How many devices do you want to connect? Even low-end receivers generally have enough video and audio inputs for a CD or DVD player, a VCR, and a cable box or satellite receiver. Mid- and high-priced models usually have more inputs, so you can connect additional devices, such as a camcorder, a personal video recorder, or a game system.

The number of inputs isn’t the only issue; the type also matters. Composite-video inputs, the most basic type, can be used with everything from an older VCR to a new DVD player. S-video and component-video inputs are used mostly by digital devices such as DVD players and satellite receivers. If you have such digital devices or may add them, get a receiver with a few S-video and/or component-video inputs. Both can provide better video quality than composite-video.

All these video inputs require a companion audio input. The basic left/right audio inputs can be used with almost any device to provide stereo sound. A turntable requires a phono input, which is available on fewer models than in years past.

To get multichannel sound from DVD players, digital-cable boxes, and satellite receivers, you generally use a digital-audio input. With this input, encoded multichannel sound is relayed on one cable to the receiver, which decodes it into separate channels. The input on the receiver must be the same type--either optical, the more common type, or coaxial--as the output on the other device. You usually must buy cables, about $10 and up, for digital-audio, S-video, and component-video connections.

What kind of sound do you want from movies? All new digital receivers support Dolby Digital and DTS, the surround-sound formats used on most movies. Both provide 5.1 channels. Most receivers also support Dolby Pro Logic, Pro Logic II, and sometimes Pro Logic IIx. If you want the latest type of surround sound, look for a receiver that supports Dolby Digital EX and DTS-ES. These offer 6.1 or 7.1 channels, subtly enhancing the rear surround. Fairly few movies using these formats are available, but offerings should increase.

What kind of music do you like? Any receiver can reproduce stereo from regular CDs. Most models have digital signal processing (DSP) modes that process a CD’s two channels to simulate a sound environment such as a concert hall. DSP modes feed a stereo signal through all the speakers to simulate surround. For multichannel music from SACD or DVD-Audio discs, get a receiver with 5.1 analog inputs.

How big is your room? Make sure a receiver has the oomph to provide adequate volume: at least 50 watts per channel in a typical 12-by-20-foot living room, or 85 watts for a 15-by-25-foot space. A huge room, plush furnishings, or a noisy setting all call for more power.

Is the receiver compatible with your speakers? If you like to blast music for hours on end, get a receiver rated to handle your front speakers’ impedance. Most receivers are rated for 6-ohm and 8-ohm speakers. If used with 4-ohm speakers, such a receiver could overheat and shut down.

Is it easy to use? Most receivers have legible displays and well-labeled function buttons. Some add an onscreen menu, which displays settings on your TV screen. An auto-calibration feature adjusts sound levels and balance to improve the surround effect. Models with a test-tone function for setting speaker levels help you balance the sound yourself.

Two tips: When deciding where to place your receiver, allow 4 inches or so of space behind it for cables and at least 2 inches on top for venting to prevent overheating. If setting up a home theater is more than you want to tackle, consider calling in a professional installer. Retailers often offer an installation service or can refer you to one.

Copyright © 2002-2006 Consumers Union of U.S., Inc.

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