MP3 Players and Rechargeable Batteries

Rechargeable batteries are the best option for MP3 players. Not only are they better for the environment, they are also cheaper in the long run. Many MP3 players use lithium-ion batteries that are good for about 500 recharges before needing to be replaced. Players which use AA or AAA batteries can use Nickel Metal Hydride (Ni-MH) rechargeable batteries.

A battery charger is an essential part of any MP3 player kit. Although some players allow you to charge the battery by plugging it into the USB port of a computer, it is more convenient to have a stand-alone battery charger with an extra battery pack. This allows you to keep your MP3 player up and running at all times.

MP3 Player Features That Consume Extra Battery Power

Certain audio formats use more power than others. The least processor intensive audio format is MP3 encoded at 128 bits per second. But if you have a lot of songs in WMA format with DRM (Digital Rights Management), they require considerably more processing power for playback, meaning correspondingly less battery time.

Other things that consume extra power include audio processing such as equalization, high-volume levels, photo display and videos. Video probably places a higher demand on battery power than any other MP3 player feature.

Hard drive audio players also tend to consume more power than flash memory audio players. This power consumption increases the more you use your hard drive. If you're constantly browsing your directories and looking at photos while listening to music, your battery will not last as long.

Batteries for MP3 Players

Most people buy a portable audio player for its portability. Being free to take your music with you everywhere you go is one of the big attractions of MP3 players. This portability, of course, is dependent on battery life, so paying attention to battery specifications is a good idea when buying an MP3 player.

Most manufacturers rate the playing time of their MP3 players. This figure refers to the number of hours of continuous music playback that can be expected on a full battery charge. It can range considerably - from 10 hours up to 35 hours.

When looking at manufacturer's specifications, keep in mind that they are most likely at the high end and represent the playing time under ideal conditions. For example, if the manufacturer rates their MP3 player at 20 hours, this probably means 20 hours of continuous playing (stopping and starting the player uses more power), with no extra features like screen displays being used.

Of course, you don't have to power your MP3 player with batteries - it can be plugged into the wall with an AC adapter or draw power from the computer. Some people use their portable players as part of their home stereo system, so an AC adapter would be the perfect power source for this kind of situation.

Additionally, for those who like to listen to their MP3 player in the car, an adapter that draws power from the cigarette lighter is ideal.

Digital Rights Management (DRM)

MP3 files can be traded very easily, creating a vast inventory of "free" music. The music industry is strongly opposed to unrestricted MP3 distribution, of course, because of fears of lost revenue, and has sanctioned a form of Digital Rights Management (DRM) to protect their interests.

In the days before the CD, it was possible to copy records to tape but each subsequent generation would cause the audio signal to be degraded. Record companies weren't overly concerned about losing revenue to this type of copying, because they felt that consumers would not accept the inferior quality of copies. Digital media changed all that - exact copies can be made any number of times without degradation. Digital media is also much easier to distribute worldwide via Internet.

As soon as Internet MP3 trading became widespread the music industry clamped down hard. They filed lawsuits against music distribution services like Napster and Kazaa and succeeded in prosecuting individuals who were caught exchanging MP3s.

The music industry wanted a system to prevent consumers from freely copying and trading music. Several types of Digital Rights Management have been developed and at the present time, every online music store that operates in the United States uses some form of DRM.

Consumers who buy songs from Internet music stores usually receive them in either WMA or AAC format. AAC is used for the Apple iPod, while WMA is used for most other types of MP3 players. DRM can be integrated into both of these formats.

A typical DRM scheme limits the number of times a song can be copied or burnt to CD. There may also be limits to how the songs are used on private networks - AAC songs can only be heard on five computers at one time.

Napster uses another approach - users can download and listen to any number of songs for a monthly fee, but those songs cannot be burnt to CD unless the user pays an extra fee. If a payment is missed, all of the songs on the computer are rendered inoperable.

Is DRM Good?

Many view DRM as unnecessarily restrictive. After all, if you buy a CD from a music store, you have the right to copy that CD, rip it to your computer and sell the original copy. If you buy a song from an Internet music store you do not have any of those rights. What's more, the online vendor can change the terms of sale at any time after the purchase. We have already seen this with Apple - they changed the CD burning rights from ten copies to seven, applied retroactively.

In effect, the music that you "buy" from an online music store is not yours. Your right to use it can be taken away at any time because of a change in policy or because you missed a monthly payment.

And in spite of the supposed protection that DRM offers to copyright holders, it can easily be circumvented. DRM songs which are burned to CDs have no restrictions - the CD can be used however the user wishes, including copying, ripping and converting to (non-restricted) MP3.

So DRM is restrictive and seemingly ineffective. It does not prevent the illegal distribution of MP3s. The music industry has yet to come up with a fair and effective way to protect its copyrights.

Features of MP3 Players

The popularity of MP3 players means that there are hundreds of models to choose from. This variety brings with it a number of options which can be confusing to the average buyer.

There are basically two types of portable audio players - flash memory or hard drive. There are also portable CD players, but these are becoming less common because they have problems with audio skipping.

The major difference between flash memory and hard drive MP3 players is their storage capacity. Hard drives usually have several times the storage capacity of flash memory so if you have thousands of songs that you want to store on your MP3 player, you are probably better off with a hard drive.

The major drawback to hard drives is that they are subject to skipping and audio dropouts. The problem is not as severe as with CD drives, and the technology is improving all the time to minimize this, but the fact remains that if you use your hard drive MP3 player while you are jogging or doing other vigorous activity, you are likely to experience dropouts.

Flash memory MP3 players, on the other hand, are completely stable even under the most demanding conditions. That is because there are no moving parts - audio files are stored in computer memory.

Both flash and hard drive MP3 players can be used as data storage devices as well as for audio playback. Computer data can be transferred to and from the MP3 player for easy portability. If this is a feature that you are interested in, the extra capacity of a hard drive MP3 player allows you to store more files.

What are the storage capacities of each type of player? The maximum size of flash players is about 4 GB, while hard drives up to 100 GB are available.

File Formats

Virtually every portable audio player is capable of playing MP3 files, but that is not the only kind of file compression format available for audio files. WMA files are very popular, and the Apple iPod uses the AAC format. Both of these formats offer higher sound quality and smaller file sizes than MP3.

Audio files can be converted from one format to another, but this can be a bothersome extra step for most people. Be sure to choose a portable audio player that supports the file format you are most likely to use.

Other Features

The type of navigation system on any MP3 player is an important buying consideration. It should be easy to find particular files, especially on a hard drive which may have thousands of songs. An easy to read screen and simple controls will allow you to find songs efficiently.

Many portable audio players have extra features such as FM radio, a built-in microphone for voice recording, outputs for connecting the portable player to a home stereo system, and color displays for viewing photos or album art. Many of the latest generation of players support video playback.

Consider carefully which features you are likely to need. This will help you narrow down your choice and make it easier to find the ideal MP3 player.

What is MP3?

MP3 (MPEG-1 Audio Layer 3) is easily the most recognized digital file format. Almost everyone associates MP3 with music, and this recognition factor is due in large part to the music industry's well-publicized legal battle against MP3 distribution. Even though there is a strong association between music and MP3, many people have no idea what MP3 actually is.

MP3 is a compression algorithm that reduces the size of audio files considerably. Audio data in the form of stereo CD recordings takes a tremendous amount of hard drive space, so before the development of audio compression, trading audio files was impractical. Thanks to MP3, audio files could be compressed to about 1/10 of their original size while still retaining good audio quality. This allowed people to upload and download songs on the Internet, bringing the full wrath of the established music industry on music distribution services like Napster.

Today, the music industry has embraced MP3 to some extent, and Internet web sites such as Apple's iTunes allow people to download songs for a fee.

Typical audio CDs are recorded at 44,100 Hz and 16 bits. This means that 44,100 audio samples are recorded each second and each sample is 16 bits. This is a constant data stream which is equivalent to about 10 MB per minute of stereo audio.

MP3 is a compression algorithm that works by throwing away some of this data, particularly frequencies which are beyond human hearing. The trade-off is reduced sound quality, but for many people the difference is not noticeable. Sound quality can be improved by encoding the audio at higher bit rates, but this results in larger files.

The big advantage of MP3, of course, is the compact file size. Audio files which are encoded at 128 kb per second are approximately 1/11 the size of the original audio file. As well as permitting Internet distribution of songs, the small size of MP3 files has also spawned the MP3 player market. MP3 players are compact devices (sometimes no bigger than a cigarette lighter) that can hold hundreds of songs. MP3 players are currently one of the hottest consumer items in the world.

The process of applying an MP3 algorithm to an audio file is called encoding. For playback purposes the file must be decoded. For this reason, audio players need a codec (enCOder / DECoder) to play MP3 files. These codecs are included in virtually every portable audio player.

MP3 is not the only kid on the block, however. There are many other formats for compressing audio. Support for these alternative formats is not universal, so when shopping for a portable audio player, one of the big considerations is the type of files it can handle.

The second most popular format after MP3 is WMA (Windows Media Audio). This is a Microsoft format that claims to offer higher audio quality at lower bit rates. Lower bit rates translate into smaller file sizes, one of the reasons for the popularity of WMA.

Apple iPod portable music players support the AAC (Advance Audio Coding) format. AAC allows more than two audio channels (up to 48) and handles higher frequencies better than MP3. The result is better sound with smaller files.

Another format that is growing in popularity is Ogg Vorbis. This is an open-source codec that carries no licensing fees and has a sound quality equal to or better than MP3.

For those concerned with audio purity, many players also support uncompressed audio files (WAV). However, at 10 MB per minute, very few WAV files can be stored on the typical portable audio player.