If you have finally realized that the compact disc (CD) is here to stay and you're ready to make your first purchase of a player, here are some things you'll need to know.
First, like record players, all CD machines are not created equal-some sound and work better than others. If you have an "educated ear," you should plan to take a player or two home for a trial period with your own system, rather than trusting the sound you hear in the store.Here are some of the terms and features you should be familiar with, before you head for the store.
The digital information, stored in "pits" on a CD, is "read" by a laser beam pickup. Some players use a lens system to split the laser light into three beams-the idea being to read the stored information more thoroughly. Can an expert hear the difference between a SINGLE-BEAM PICKUP and TRIPLE-BEAM PICKUP? No way! A single- may actually be preferable to a triple-beam, simply because it is a less complicated device, with fewer potential problems.
OVERSAMPLING refers to the number of times per second the digital material contained on each disc is examined. The standard sampling rate used for recording on CDs is 44,100 times per second - usually referred to as 44.1kHz. Theoretically, by "looking" at the digital information at a higher rate, greater clarity and definition should result. Therefore, two-times oversampling (88.2kHz), four-times (176.4), or even eight-times oversampling (352.8) filters should provide higher fidelity. However, in practice, high oversampling rates can create other problems. My advice is to not worry too much about oversampling rates; let your ears tell you which unit to buy.
A DIGITAL-TO-ANALOG CONVERTER (DAC) is responsible for changing the digital signal back into an analog signal, for amplification and subsequent reproduction by your speakers. Some players have only one DAC, higher quality units have two (one for each stereo channel), and a few machines even employ four DACs (two per channel). Separate, highly-linear DACs for left- and right-channels are best.
LINEARITY speaks to how accurately the digital-to-analog signal conversion is made. High quality digital-to-analog converters will provide precise linearity of the audio frequencies-no dips or peaks in frequency response. The more linear the DAC, the better it is. But don't be fooled by the "bit wars"-advertising hype can be misleading. A 16-bit DAC with excellent linearity will provide superior sound to an 18- or 20-bit DAC with only modest linearity. If you have a doubt, ask to see a graph showing the performance of the unit's DAC(s) - flatter is better.
If you listen to your records less frequently than you might, because they require too much work to play, a compact disc machine will be a pleasant addition to your system. Even inexpensive CD players are now able to offer a whole list of sophisticated, "listener friendly" features. For example, most sport wireless, remote controls.
PROGRAMMABILITY means that you can tell the player the order in which you wish to listen to the disc's selections. No more having to move an awkward needle and tone arm to a specific cut - a touch of the ADVANCE button will do the job in an instant. And, if you want to hear the disc over and over, a tap of the REPEAT button is all it takes.
Some players even have a MEMORY that allows you to "teach" it your favorite cuts on each CD. This means that if you hate a specific song on a frequently played disc, the player will "remember" never to play it again. Or, it can be "taught" to play any selections in a specific order.
One of my favorite features offered on many CD players is RANDOM PLAY or SHUFFLE PLAY, which means that you will never be bored by hearing songs played in the same old sequence.