Audio - When It's Time to Buy that New Stereo System

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Buying new audio equipment can be a confusing process even for the most avid music fan. Here are some guidelines to help you buy your new speakers, amplifier and tuner. Regardless of how you intend to use your new system, speakers are the most critical element in audio reproduction. They are the pieces that change the electrically produced audio signals into something your ears can hear.

To judge effectively what speaker system is best for you, bring a few of your favourite CDs or DVDs with you to the retailer's shop. When comparing speakers, try to evaluate them only two pairs at a time. Don't try to compare too many speakers in one sitting, and take frequent breaks between sessions. Once you've selected a pair, spend time listening carefully. The goal of this exercise is to ensure that the speakers reproduce music and video soundtracks as accurately as your budget allows.

Pay particular attention to the following characteristics of a good-quality loudspeaker system:

1. smooth treble response
2. good bass projection
3. good transient response
4. favourable distortion characteristics
5. clarity of auditory texture

At the heart of any system is the amplifier, which serves as a selection point for the various programme sources connected to it. Buy as much power as your budget allows. A low-power amplifier may not be able to handle the momentary peak demands placed on it by the loud orchestral crescendos of symphonic music. At the peaks, the amplifier's circuits could be overdriven into distortion, due to the lack of reserve power. The amount of power required depends upon your listening habits and the size and furnishings of your room. A room with wood or tile floors and hard walls and furniture will possess a reverberant tonal quality. One that contains carpeting, draperies, and thickly upholstered furniture possesses deadened tonal qualities.

Another important consideration is the number and type of inputs. Most units should be able to accommodate a tuner, a CD player, a DVD player, audio from a VCR, and a recording device. Many newer amplifiers or receivers have a switch marked MD for Minidisc. This Minidisc input may also be used for any high-level audio device, such as a tape machine or VCR. Older amplifiers frequently have an input labelled AUX. This high-level auxiliary input can also accept a CD or DVD player's audio feed.

Sensitivity of tuner or receiver is key

The most commonly selected programme source for many audiophiles is their tuner. When shopping for a tuner, there are three main criteria to consider: sensitivity, selectivity, and capture ratio. Sensitivity is measured in decibels femtowatts (dBf). The lower the number shown, the more sensitive the tuner is to weak signals. Selectivity is expressed in decibels (dB). The higher the selectivity rating, the better the tuner is in distinguishing between stations that are close together on the dial. Capture ratio refers to a tuner's ability to capture the stronger of two stations' signals emitted on the same frequency. Capture ratio is also expressed in decibels (dB). The lower the number, the better the tuner.

These criteria also apply to receivers, which incorporate both a tuner and an amplifier into one unit. When selecting a receiver, listen to it carefully using a compact disc as the input source. Avoid radio signals since many radio stations employ limiting and compression, and this signal processing often emasculates the dynamic range of the music, making it unsuitable to evaluate a system fully. Another aspect of interest to readers who listen to CBC Radio One or La Chaine D'Information is the fact that in some major cities AM transmitters are still used for these services. As AM tuning ranges do not exist on many newer tuners and receivers, verify that your choice has this capability while you are shopping, if it is required.

And finally, listening at home

Once your new equipment is at home, read all of the manufacturer's directions carefully before beginning installation. Be sure that all of the required cables are connected correctly before turning the system on. Don't overlook the FM or AM antenna while doing the installation. Better radio reception is the reward for using a better antenna than the ubiquitous dipole antenna shipped with most receivers or tuners. Position your speakers so that the tweeters are at eye level when seated. Speaker cabinets should be installed approximately a foot from the wall, from 4 to 6 feet apart. After turning on the new system for the first time, the FM tuner should be played through the speakers at low volume for 12 to 24 hours. This will counteract the stiffness of the speaker drivers' cones. You can also expect the sound to improve as these cones age. Finally, settle into your favourite chair, relax, and enjoy your new system.