Mp3 player Audio Compression

There are several different audio compression formats including MP3, WMA and AAC. It is safe to say that every MP3 player can play MP3 files, but not every player can handle WMA or AAC.

WMA (Windows Media Audio) is a Microsoft supported format and is used for audio files which have been protected with DRM (Digital Rights Management). Many of the songs available for purchase from Internet stores like Napster and MSN Music are in WMA DRM format, so if you plan on purchasing from these stores, you need an MP3 player which supports the format.

AAC (Advanced Audio Coding) is used almost exclusively by the Apple iPod. If you have an iPod, it will be difficult to trade AAC files with a friend who has a different type of MP3 player. Sure, they can be converted, but that's an extra step.

Other, lesser known formats such as Ogg Vorbis and MP3 Pro are supported by relatively few MP3 players even though they offer superior sound quality and smaller file sizes.

Mp3 player Displays

There are a few MP3 players which have no screen, but they are a rare breed. Most MP3 players will have at least a small LCD display that shows you the current song being played. Larger displays are necessary for MP3 players which have larger memory, because you need to be able to navigate through the file structure to find individual songs.

An easy-to-read screen is essential. If it is too small to see clearly, or cannot display an adequate amount of information, it is next to useless. If you are going to use your MP3 player at night, the display should have a backlight for viewing in dark conditions.

Displays can be either monochrome or full color. Color displays are included in the more expensive MP3 players, and are necessary for players which have photo and video capabilities. The bigger the display the easier it is to read and more information can be shown at one time, but bigger displays also draw more power, thus shortening the battery life.

Other Mp3 player Features

Some MP3 players have built-in microphones, FM radios, stop watches and personal managers. The value of these features is an individual choice. If you need to make verbal notes or record meetings the built-in microphone is a handy feature. Stop watches are useful for the athlete who likes to have a music background during workouts. FM radios?  You don't need them for the music, but they are useful for getting weather and traffic reports.

Several MP3 players have personal managers which can be synchronized with your computer address book or calendar. This is a great feature for people who are on the road and need a handy way to have their schedule and contacts close at hand.

Other useful accessories include a case to protect the player from scratches, an armband or belt clip for hands-free listening, a remote control, extra batteries and a power supply for indoor stationary use.

For those who plan to use the MP3 player in the car, an adapter that allows the sound to be heard over the car audio system is very handy. These come in two types - an FM transmitter that sends the sound to the FM radio, and a cassette adapter that allows you to use the cassette deck to listen to your MP3 player. Don't forget to get a car power adapter at the same time.