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MP3 is a revolutionary digital audio format developed by Fraunhofer-Gesellschaft and Thompson Multimedia in the late 1980s and brought to the mainstream through the Internet in 1997. MP3 is short for MPEG (Moving Pictures Experts Group) Layer - 1 , the group that help make MP3 an international standard.
What MP3 Is
MP3 is a compressed audio format that allows for smaller file sizes with similar sound quality to PCM WAV format, the format found on normal music CDs you would buy in a store. Thompson and Fraunhofer helped develop the coding algorithm, or system of rules and processes, that encoded audio to this incredible format. For more on exactly how this encoding technology works, see our section entitled Inside the MP3 Codec.
Why MP3 is Popular
The popularity of MP3 comes from its practical uses. Music tracks in WAV format are extremely large in file size, averaging around 50MB in size. Since it is so large, it is not practical to send WAV files through email or offer them for download on the Internet. MP3, however, compresses WAV audio on average of 10 to 12 times smaller than the original size. The result is audio tracks around 3 to 4 MB in size, perfect for downloading and sending through the Internet. Thus, custom MP3 format CDs can be created with 10 to 12 times the amount of tracks of a normal 12-15 track audio CD, producing CDs with over 100 tracks easily. The format is also popular for turning your PC into a jukebox of hundreds or thousands of songs or loading them into a portable mp3 player and taking your music collection wherever you want.
As of now, you cannot buy MP3s in a store on a CD. Therefore, you can either make them yourself or get them from others who have made them.
To make your own MP3s, you need a CD with music, a computer with a CD ROM that supports digital audio extraction (also called ripping, most CD ROMs support this), space on your hard drive, and mp3 ripping software. The process than is simply putting your CD in your computer CD drive and then running the mp3 ripping software. Each software program has its own way of letting you do this and you will need to become familiar with each program. I recommend Easy CD Ripper as one of the easiest rippers to get started with and use.
Getting MP3s from Others
If you don't want to make your own MP3s, you can get them from someone else. The most popular ways include using file sharing software (similar to Napster) and downloading them from someone else over the Internet. Although this method is popular, there are some risks. Most music is copyrighted and if you don't own the CD of the songs you want to acquire, you will technically be breaking the law. Also, there is the risks that downloading files over the Internet will contain viruses or other unwanted material although the majority of files will probably be safe. Other ways of getting MP3s is from free MP3 sites like EMusic or by copying files from another person's MP3 format CD that they have created.
Other free legal MP3 download sites include:
Since MP3 is a data format and not an audio format, you cannot listen to these files in a normal CD player. MP3 needs a player designated as an MP3 player to decode the audio and produce listenable music from the data.
There are many free mp3 players for download on the Internet. Winamp is the most popular and fairly easy to use. I personally like dbPowerAMP and the ability to rate your tracks so that the most popular get played more often. Take a look at our page with the above players and a couple more free mp3 players to choose from.
Other ways to play mp3 include portable mp3 players, newer home stereos and DVD players with denoted MP3 playback ability, and car mp3 players.
Since there have been so many lawsuits like the high profile suit involving Napster, many people are not sure whether MP3 is legal or not.
The issue surrounding MP3 legality is copyright. The same premise behind the copyright laws governing books and other printed material are behind MP3. The law is trying to protect artists from not getting paid when people copy and distribute there music.
In and of itself, MP3 as a format is completely legal. MP3 is merely a technology that Thompson Multimedia and Fraunhofer-Gesellschaft own a patent on. MP3 files become illegal when someone has taken copyrighted music, made copies of it, and distributed it to others without the rightful consent of the owners. Many argue that if they have bought the music they can do whatever they want with it as long as they are not making a profit. Under Digital Millenium Act, this is not true. Solid application of these laws however gets sketchy. What if you own the music and want to make copies on your computer or make your own custom CDs? Many believe, including myself, we have the right to do so. It is up to you to research the law and act according to your own ethical standards.
Since its high profile lawsuit with the Recording Industry Association of America (RIAA), Napster has almost become a household name.
Napster was founded in May 1999 by Shawn Fanning, a high school student that developed a program for people to share music files over the Inernet. The program caught on with the allure of "free music" and turned into a worldwide phenomena. However, Napster came under legal trouble and was found to be aiding copyright violation through its program. The central server was shut down by court order and the original program ceased. However, the program was bought out by media giant Bertelsmann AG (BMG) and is undergoing a reorginization.
The core concept of Napster has since inspired a whole generation of file sharing devices like KaZaa, Music City Morpheus, and BearShare. Napster may have been the single biggest influence in popularizing the MP3 format.
MP3 file sharing programs are software tools that let you download mp3 files from other users of the same program that have allowed files on their computer to be shared. Napster is the father of all mp3 file sharing programs.
What do these programs do?
File sharing programs in general let you swap any kind of file with other people that are connected a network through the software. You can trade pictures, movies, text documents, and music files by downloading them from another person's computer. The software only lets you access files that a user has opened to the public. You can in turn offer files on your computer to be downloaded by others. Most file sharing programs today include filters to help you get what you want and stay away from what you don't.
Are these programs safe?
Any time you connect your computer to a network or even go on the Internet you are at some level of risk to hackers and viruses. Most file sharing programs try to minimize the risk through security measures but you are still putting your trust in their programming and maintenance skills. The biggest risk with MP3 file sharing is viruses disguised as MP3 files. However, dilligent and careful use of your virus software should catch most problems.
Where to get MP3 file sharing programs
The most popular MP3 file sharing programs of 2002 are KaZaa, Music City Morpheus, BearShare, iMesh, LimeWire, and QTraxMax. For a guide on recommended file sharing tools and risks, see Team-MP3's file sharing guide.
What it Is
An MP3 ripper is a software program that takes audio from a CD, extracts it, and converts it to MP3 all in one process. These are also commonly known as ripper and encoder combos. CD rippers, digital audio extractors (DAE), and cd grabbers are essentially the same thing. They all take audio from CD but may or may not convert it to MP3.
How do MP3 rippers work?
There are two ways that rippers get audio from CD; digital extraction and analog extraction. Digital extraction is the most accurate method as it seeks to take the exact data on a CD and copy it to your hard drive before encoding to MP3. There are routines that developers can add to check and double check the accuracy of the rip. Analog extraction records the audio as it is played through the computer's sound card. Accuracy is dependant on the quality of the sound card and if the CD-ROM reads the audio correctly in light of dust, scratches, and other defects. This is the least accurate of the two methods but is one way to copy audio from newer CDs that are copy protected.
Where do I get free MP3 rippers?
Call me biased but I think MP3-Converter.com is the perfect place to get free mp3 rippers. You can find them for free in our mp3 converter freeware directory or you can try out a ton more in our shareware category. Shareware programs allow you to download and try programs for free, often for 30 days before you decide to buy. These programs are often developed and supported better than freeware since most people don't like to work for free.
What is the best MP3 ripper?
I look for a couple of things in a ripper. Quality, speed, and ease of use. Most rippers on the market today do just fine in the quality area. If you want to be sure you have the very best quality cd ripper out there, check out Exact Audio Copy. The program has a bunch of routines that checks and double checks for accuracy. However the program is not fast and is not geared to beginners.
Speed varies according to product but I have been happy with the ripping and encoding combo of Virtuosa Gold. Speed is above average and the encoder is from Fraunhofer, one of the pioneers of MP3 technology.
There are two easy to use programs that I recommend for most people. They are Easy CD Ripper and CDex. I think Easy CD Ripper is the easiest to use and it performs a lot of conversions. CDex is also very good and totally free. Both produce high quality MP3 and WAV files.
If you want more advanced information on ripping and audio extraction, I recommend the following resources:
What it Is
An MP3 encoder is software that uses an MP3 Codec (compression/decompression algorithm) to make MP3 files. Most encoders convert WAV to MP3 although many can convert other formats such as WMA, Real Audio, Ogg, and more.
There are very few unique encoders. Most software out there uses only about 4 main encoding engines due largely in part by the patents held by Fraunhofer-Gesellschaft and other companies that helped produce the ISO source that MP3 is based on. Although no one company owns exclusive rights, MP3 software developers must pay a licensing fee to use any of the patented mp3 encoders which is very expensive. The major encoding engines are LAME (non-ISO source), BladeEnc, Fraunhofer Encoders, and Xing from Real Networks.
How do MP3 encoders work?
MP3 encoders encompass the core technology behind MPEG-Layer 3. The programs work by applying a series of algorithms or rules that compress audio. Encoders intelligently detect audio data that is too high or low for the human ear to hear and gets rid of it. They also detect sounds that occur simultaneously and try to get rid of any sounds that are "masked" or made inaudable by other sounds. For a complete rundown of MP3 technology, see our Inside the MP3 Codec section.
Where do I get an MP3 encoder?
Many MP3 programs include an mp3 encoder. Check our mp3 encoder downloads page for lots of options. You can download and try all the programs listed for free.
What is the best MP3 encoder?
For speed, Xing is the fastest encoder but the quality is the worst out of all of them. For smaller file sizes, Fraunhofer's FastEnc gives excellent quality. LAME is a very good all around encoder and keeps getting faster with each release. BladeEnc is the best in quality for large file sizes but is very slow.
What It Is
An MP3 decoder is a software program that converts MP3 to another format. However, when most people mention MP3 decoder, they are talking about a program to convert MP3 to WAV.
Why You Would Want An MP3 Decoder
Since most CD players cannot play MP3 format, mp3 decoders are used to convert MP3 to WAV before burning the files to a CD. The resulting WAV files can be played on any CD player. Most MP3 files are probably downloaded from free sites or with file sharing devices and then converted to WAV for custom audio CD creation.
What is the Best MP3 Decoder?
The difference between decoders is speed, ease of use, and quailty of the resulting file. In our MP3 Decoder section, you can find links to scientific tests on the quality of some of the decoders.
My personal favorite decoder is MP3 to WAVE Converter PLUS. The program is incredibly easy to use, is fast, produces nice sounding files, and can convert many files at once for big decoding jobs. Check our decoder section for many more options. Also, many cd burning programs have decoders built into them. You can simply load MP3 files into the program and they will automatically convert them to WAV during the CD creation process. MP3 CD Burner is one such program.
What It Is
The process of writing data to a CD is often called "burning". An MP3 burner is a software program that converts (burns) MP3 to CD. The resulting files on CD will either be in WAV or MP3 format, depending on the capabilities of the software. WAV files on CD are playable in any CD player whereas MP3 files on CD are audible only on special MP3 compatible players. Your computer CD ROM will be able to play MP3 CDs in conjunction with Windows Media Player, Real Player, or other supporting software.
What is the Best MP3 Burner?
For converting MP3 to WAV CDs, I like MP3 CD Burner. The program has an easy to use interface that lets you add and burn files easily. It incorporates Burn-Proof technology in conjunction with your CD burner hardware to eliminate buffer-underrun errors, a common technological problem with CD creation that thwarts the burning process. The program is very cost effective and is backed up by Acoustica's excellent support, quality guarantee, and all registered users get free upgrades of the program for life.
For making MP3 CDs, I like Audio CD Maker from Avantrix. This program has undergone many improvements and it easily burns quality MP3 format CDs, offers the same Burn-Proof technology as MP3 CD Burner, and is also very inexpensive.
For making both MP3 and WAV CDs, I suggest Nero Burning Rom. Nero has a ton of features, incorporates Burn-Proof technology, has an easy to use burning wizard for quick CD creation, and is fast. I used to use Easy CD Creator for all my burning but switched to Nero when I got the software with my new burning hardware. Nero is much faster and easier to use than the old Easy CD Creator version 4 I had previously. Although Nero is a more expensive program, it comes free with some CD burners.
Are There Any Free MP3 Burners?
This feature is the hardest to find free in the MP3 software world due to it demanding more support and development. Music Match Jukebox has a burning feature in its free version but it only burns at 1X which is very slow (the same amount of time it would take all the tracks to play - 4 min. play time = 4 min. burn time). Paying for the Plus version of the program gives users faster burning.
What It Is
WAV is a file format developed by Microsoft and IBM for use on the PC. The format was built into the Windows 95 operating system and quickly became a standard. The format ends with the .wav file extension.
Uses of the WAV Format
WAV files are typically large in file size due to the high quality the format and are used for CDs. An average pop music song is around 50MB in size. WAV files can be made smaller and converted to MP3 format through a process called encoding. This process always yields some kind of quality degradation, depending on how much compression is applied. When MP3 is converted to WAV, the process is called decoding. When MP3 is decoded to WAV, there is no increase in sound quality whatsoever, the file merely increases in size and can be read by common CD players. CD rippers (or CD recorders / extractors), are sofware programs that record CD audio to WAV format on your hard drive.
WAV format is necessary for editing sound files. Technically, MP3 cannot be edited to remove defects or add effects, it must first be converted to WAV format. A WAV editor is needed to alter the WAV file. Some programs like Rip Edit Burn include a WAV editor in the program.
There is one program that will actually compress WAV files without a loss in sound quality. Monkey's Audio compresses WAV files to as much as 60% of the original file size. Files are then saved in .ape format and can only be read by a few compatible players. The program is free and great for those who want to store high quality sound files and want to maximize data storage space at the same time.
For more advanced information on WAV audio, see the following technical resources:
What It Is
WMA is a file format developed by Microsoft to compete with MP3. The letters stand for Windows Media Audio and the file format ends with the .wma extension.
Is WMA Better Than MP3?
The latest release of WMA technology is version 8 which is the best yet. I believe WMA files produce better sounding files than MP3 at similar bitrates. My entire music collection is encoded in WMA 8 format at 128kbps and it satisfies my picky ears. The drawbacks of WMA is that it is a proprietary format meaning that Microsoft charge whatever fees they wish to developers that want to incorporate support for the format in their software. The format also incorporates differing levels of copyright protection which angers some users, limiting them to what they can do with their own music. However for simple encoding and archiving for a jukebox collection, it suffices.
How Do I Make WMA Files?
Making WMA files requires a WMA encoder. Windows Media Player comes with a free CD ripper and WMA encoder, enabling you to easily convert CD audio to WMA on your computer. For more advanced WMA converting and organizing tools, see our WMA converter section.
For more information on WMA, see the following resources:
What It Is
Real Audio is a technology developed by Real Networks that includes streaming audio and media as well as a compressed digital audio format to compete with MP3. Real audio carries the .ra file extension and Real Media uses .rm.
Is Real Audio Better Than MP3?
Since Real Audio is a proprietary format like WMA, its uses are limited to only the Real One Player and a few supporting portable audio players. The quality is as good or slightly better than MP3. Only your own personal listening tests will show if you prefer Real Audio encoded files over MP3.
How Do I Make Real Audio Files?
Making Real Audio files requires the Real One Player with included Real Jukebox. After you download and install the program, you can find information on how to convert to .ra format. Real Jukebox includes a cd ripper and encoder.
What It Is
Ogg Vorbis is an open source digital audio technology designed to compete with MP3. Unlike MP3, Ogg Vorbis has no patents and can be used and developed by anyone. Ogg Vorbis is part of the open source Ogg project that aims at creating a completely free and open multimedia system. Ogg Vorbis files end with the extension .ogg and require supported players for listening.
Is Ogg Vorbis Better Than MP3?
Ogg Vorbis developers claim they use a superior psychoacoustic model that yields better sounding files than MP3 at comparable bitrates. I suggest a listening test yourself to compare an MP3 and Ogg Vorbis file encoded at the same bitrate.
How Do I Make Ogg Vorbis Files?
Software for making Ogg Vorbis can be here.
For more information on Ogg Vorbis, see:
What It Is
mp3PRO is a file format developed by Coding Technologies to improve on the MP3 format. The company claims file sizes that have the same quality of MP3 at half the bitrate and file size.
Is mp3PRO Really That Good?
So far, mp3PRO has really disappointed MP3 fans. Complaints center around muddy sounding files and lack of compatability with most MP3 players. Coding Technologies have kept a tight handle on its proprietary format have really squelched development of software that handles the format.
My personal listening tests have given me mixed results. 64 kbps is the default (and currently only) option to encode files with the demo encoder. For 64kbps, it is superior to MP3 LAME encoded files at 64kbps. However, there was a substantial lack of clarity in the instruments especially background vocals, bass guitar, and drum cymbals. The quality is definitely better than what you would hear on your FM radio, but still has a ways to go before it supplants MP3 as the dominant file format.
How Do I Make mp3PRO Files?
A demo encoder and player is now available for download. The program does not rip from CD. You need to have WAV files available to convert to mp3PRO for this program. mp3PRO Encoder download
For more information on mp3PRO, see the following resources:
What It Is
CDDB is an online database of CD album, artist, track, and genre information. Software programs can make a request of the CDDB to download CD information for automatic track naming in the program. This is particularly useful for ripping CD audio and having your tracks named automatically rather than manually. Computer CD programs, like the one that comes with your Windows operating system, now automatically request CD album and track information for you to view through the CD playing program.
There are currently two popular CDDB services on the internet. The original database has been renamed Gracenote and is a profit making entity. FreeDB is an open source CD information resource that is free for developers and the public to use.
For more information on CDDB, see the following resources:
The very best place to get Macintosh MP3 software and read reviews is in our Mac MP3 converters section. The second best place to get Mac software would be Mac Digital Audio.
For an excellent tutorial on Linux and MP3, see the Linux MP3 How-To.
Making your own audio CDs is a large part of MP3s popularity. Most store bought CDs contain many songs you don't end up listening to. Making your own CDs takes care of that.
To make your own CDs, you need:
If you don't have a cd burning drive, take a look at models from TDK, Plextor, Lite On, Cendyne, and TEAC at your local computer store or on the Internet. These companies usually produce high quality products. They will also include the necessary software for burning your own CDs. If you need CD burning software, see our CD burner download section.
For casual use, I would get inexpensive CD-R media (CD-RW is more expensive and not compatible with many CD players). I use Memorex, TDK, or any other name brand that is on sale at the local computer store. Ordering media over the Internet is usually much more expensive due to shipping charges. If you want the very best quality CD-R media and price is not an issue, try Kodak.
If you don't have music tracks on your computer to burn onto CD, see our guide to getting MP3s for a couple of ways to get music files. For use in most music players, it is easiest to have WAVE files for burning. If the WAVE files have not been converted to another format (i.e. MP3, WMA etc.) they will inherently have the highest sound quality and not need to be converted before burning. If all you have is MP3 files, many programs (like MP3 CD Burner) convert MP3 to WAVE during the burning process so your final CD will be ready for play in any CD player.
Once you have all the necessary equipment, the process is easy as following the burning directions in your software program. Many programs include a guide for burning files on your computer to CD. If you are having trouble with this, download and try MP3 CD Burner. The burning process is very easy and the help menu in the program provides a step by step guide to CD creation.
When making your own CDs, it is important to know that normal CD players in your stereo, car, or home theater system can only read WAV (.wav / WAVE) format unless otherwise specified. Therefore, if you burn an MP3, mp3PRO, WMA, or Real Audio format CD, a regular CD player cannot read it. Only players specified as MP3, mp3PRO, Real Audio and WMA compatible can play those formats.
MP3 ripper software is a program to convert CD to MP3. The best place to get this software is here at MP3-Converter.com. Search through our huge shareware mp3 converter directory and look for "Ripping" in the "Function" column of the directory.
For free mp3 ripper sofware, search our free mp3 converter directory and look for "Ripping" in the "Function" column of the directory.
What is the Best MP3 Ripper Software?
For high quality MP3s, I like Virtuosa Gold. The ripper is fast and accurate and the program uses a Fraunhofer encoder (creators of MP3) for converting to MP3. The easiest to use mp3 ripper is Easy CD Ripper.
For more information on MP3 ripping, see:
MP3 encoder software is a program to convert to MP3. The best place to get this software is here at MP3-Converter.com. Search through our huge shareware mp3 converter directory and look for "Encoding" in the "Function" column of the directory.
For free mp3 encoder sofware, search our free mp3 converter directory and look for "Encoding" in the "Function" column of the directory.
What is the Best MP3 Encoder Software?
The best encoder software uses either a Fraunhofer or LAME encoder to make MP3s. An excellent program that uses the Fraunhofer encoder is Virtuosa Gold. Music Match Jukebox also uses a Fraunhofer encoder. For LAME encoding see Easy CD Ripper or MP3 to WAVE Converter PLUS.
For more on MP3 encoders, see:
MP3 decoder software is a program to convert to MP3 to WAV. The best place to get this software is here at MP3-Converter.com. Search through our MP3 decoder section for a large list of decoders.
For free mp3 decoder sofware, search our free mp3 converter directory and look for "Decoding" in the "Function" column of the directory.
What is the Best MP3 Decoder Software?
What you want most out of an mp3 deocoder is one that is fast and produces a nice clean WAV file. Part of the WAV quality depends on the original MP3 that is being encoded. When converting MP3 to WAV, you do not achieve any higher quality, all you want is a WAV file that is as close as possible to the original. MP3 to WAVE Converter PLUS and dbPowerAMP are two high quality MP3 decoding programs.
For more on MP3 decoders, see:
MP3 burner software is a program to convert to MP3 or WAV to CD. The best place to get this software is here at MP3-Converter.com. Search through our mp3 converter shareware directory and look for "Burning" in the "Function" column of the directory..
For free mp3 burner sofware, search our free mp3 converter directory and look for "Burning" in the "Function" column of the directory.
Some popular MP3 burners:
For more on MP3 burners, see:
MP3 Editor is a generic term for a program that edits some facet of an MP3 file. MP3 editors might attempt to improve the sound quality, add effects, or change the ID3 tag information that contains album, artist, and track information.
There are a few programs that can help you alter the actually sound of an MP3 file, either to clean up clicks and hisses or remove and add actually audio data. MP3 Trim is a free mp3 editor that lets you remove parts of the file, adjust the volume level (normalize), and add fade in and fade out between tracks.
Some MP3 files also carry album, artist, and track information in added data called ID3 tags. You can add and edit this information with an ID3 tag editor. Some MP3 converter programs come with this ability and there are some programs dedicated to it. Advanced MP3 Catalog is both an ID3 tag editor and utility to organize your collection.
What it Is
An MP3 recorder is a software program that captures audio that is played through a computer's sound card and then encodes that audio to MP3. MP3 recorders can capture audio from online sources, microphones, tapes, records, and any other audio source that is connect to and played through a sound card.
Where to get MP3 recorders
There are a few programs that will successfully capture audio and convert it to MP3. WAVE Creator is a value priced tool custom tailored for MP3 and WAVE recording. It will capture audio from your sound card or any line-in source through the card and convert it to MP3. You can also edit the WAVE before you convert by adding sound effects, split file into tracks, add fade in and out, and alot more.
What it Is
An MP3 splitter is a software program that takes an MP3 file and lets you cut it into two or more smaller files. Sometimes entire albums are recorded on to one MP3 file and someone may want to break it up into individual tracks. You can also use it to make segments of songs or audio files for special sound effects or other multimedia projects.
Where to get an MP3 splitter
Cool MP3 Splitter is a nice tool that lets you upload an MP3 file and let you choose how you want the file to be split. Multi-thread split technology is employed to get the best possible files from your master file. Other tools that can split MP3 files are WAVE Creator and Cool Edit 2000.
What it Is
MP3 to MIDI is the process of taking audio in the compressed MP3 format and change it to a completely different kind of file - MIDI. Since MIDI is not actual audio but a series of instructions for music instruments, it takes a very special kind of software to do this conversion.
Where to get a MP3 to MIDI Converter
I have only seen one program that could convert MP3 to MIDI. WAV to MIDI Converter can capture audio through a sound card and convert it to MIDI. You may want to convert MP3 to WAV before using WAV to MIDI converter. Try both MP3 and WAV formats with the program to test for the most accurate MIDI file. For an easy way to convert MP3 to WAV, try MP3 to WAVE Converter Plus. After you have converted the file to MIDI, the program will let you edit the MIDI file to your liking.
A WAV converter is a program to convert WAV files to another format. Since WAV files are very large, someone may want to compress the WAV file by changing it to MP3, WMA, or Real Audio format. Converting WAV to those formats will always result in some amount of sound quality loss, depending on how small the files are compressed. WAV can also be converted to Monkey's Audio .APE format which results in no quality loss but does not compress the file nearly as much as MP3 or WMA. WAV can also be converted to MIDI format with the WAV to MIDI Converter program. Transferring WAV files on your computer to CD requires CD burning software (MP3 CD Burner) and a CD burning drive.
Some popular WAV converters:
For more on WAV format, see:
A WAV to MP3 converter is a program that encodes WAV files to the MP3 format. The original WAV file is compressed using the technology provided by the MP3 encoder to much smaller file sizes. The resulting sound quality depends on how small you choose to compress the file. The smaller it gets, the worse it sounds because audio data is being discarded.
The best WAV to MP3 converters use technology by LAME or Fraunhofer based encoders. Fraunhofer is the original developer of the MP3 technology and can be found in programs like Virtuosa Gold, Music Match Jukebox, and Siren Jukebox. It is fantastic at lower bitrates, especially 128kbps.
LAME is an open source (practically meaning nobody owns it) encoder that has its own technology to make MP3s. It has become extremely popular due to its open source nature and nice blend of quality and speed. Here is a list of programs that use the LAME encoder.
Recommended WAV to MP3 converters: