With the move to digital music there was no longer just the physical media one had to worry about. As the years have passed more and more formats have emerged and no player on the market is capable of playing them all.
The term “MP3 player” is only good as long as the music format is actually MP3. DRM has had it’s part in confusing people and creating incompatible players and the more “high end” formats like FLAC and Vorbis are unknown to most consumers and ignored by many manufacturers. Read on for a “what’s what” on audio formats.
Before digging into the various formats (aka codecs), some terms have to be clarified – bitrate is one of them. Bitrate is the space needed for one second of music. 128kbps (Kilo Bits Per Second) = 16KBps (Kilo BYTES per second) which is about 5MB (Mega Byte) for 5 minutes of music. The higher the bitrate, the higher the sound quality, BUT that’s only true if the source format is higher than the output format. Ripping a CD to 320kbps MP3 gives you better sound quality than 128kbps, but converting a 128kbps to 320kbps won’t give you higher quality – in fact conversion might take off some quality and give you worse sound quality.
On average consumer level, 128kbps MP3 is known as CD quality. If you have any gear whatsoever capable of decent sound, 128kbps won’t be anywhere near good enough. Manufacturers tend to do estimates for number of songs a player can hold based on very low bitrates as too many consumers don’t know that audio files are different sizes. Don’t ever trust those numbers, check your music collection and see how much space YOUR music takes up.
Uncompressed audio takes up a lot of space. To make smaller audio files, like MP3 does, the software removes the part of the frequency range that tisn’t important for the human ear. Various formats compress audio in different ways and bitrate again plays a role in determining how much the audio is compressed. Sampling rate also plays a role in this and is a number measured in hertz that tell you how many samples per second the audio file is. The bottom line with sampling rate is that most your audio files will be 44.1kHz (44100Hz), and that a lower number = bad.
VBR vs CBR
Constant Bit rate (CBR) and Variable Bit Rate (VBR) are two ways of handling bitrate. Constant bitrate means you got a specific bitrate through the entire file, while variable bitrate varies depending on how big a bitrate is needed at a specific point in the music file. The chorus of a heavy metal song naturally requires higher bitrate to sound good than a pan flute solo, which is what VBR is all about. CBR is like packaging something in a oversized box, VBR is like using shrinkwrap. People tend to overdo it and use 320kbps CBR to get max quality while VBR with an average of 192 kbps (aka V2) would basically do the same thing.
DRM (Digital Rights Management) is the most evil invention since the nuclear bomb and anyone and everyone should keep away from it at all costs. Basically DRM is something music stores can slap on the files they sell so that the application you use to transfer music have to connect to a server to verify you own the file to transfer it. More and more companies shut down these servers after cutting out DRM’d files and people that bought the files can no longer transfer them to any device. DRMd files are also not compatible with all players out there and with DRM you can forget drag and drop file transfer using MSC/UMS mode. DRM’d music normally are WMA or AAC, but be aware that it’s not automatically DRM just because a file is that format. My plea to the people is to not support any music store using DRM, it’ll only cause you problems.
WAV aka WAVE is basically what most people mean with uncompressed audio. While you can compress WAV (for example like many MP3 players do for voice recording) the main use is for totally uncompressed audio both quality wise and size wise. Most players play it, few people use it – mostly because of the file size.
MP3 is the most used compressed audio format and frankly the only format you’ll ever need if you’re in the 99% group of mainstream consumers. If you’re wondering if there’s any point in using a “better” format, the short answer is no. There are audiophiles out there that swear to lossless formats and think MP3 is the devil – and that’s fine – but few mainstream consumers will ever need another format for everyday portable music listening. It’s not perfect but it does it’s job. Just make sure that you get decent quality files – not 128kbps – and if you rip the music yourself you might want to consider VBR. Using MP3 also means you don’t have to look for audio codec compatibility when looking for a new player.
Vorbis is often called Ogg Vorbis or even Ogg because it uses the Ogg container format (read the video format roundup for info on container formats). Vorbis is open source and is often considered to sound better than other lossy formats at the same bitrate, but again most consumers won’t hear any difference.
FLAC is an open source codec for lossless audio. Lossless means that even though it compresses the audio size wise, the quality is exactly the same – no quality loss. Compared to a WAV file you might get as much as 50% smaller file sizes. Being open source, it’s free to implement, but since few people use it (speaking compared to number of MP3 player users in the world) it’s not prioritized by many companies.
AAC is basically the theoretical successor of MP3, being superior in any way. Apple uses AAC for iTunes music and Sony also heavily support the format in their devices. Compared to MP3 it has the technical capabilities to beat it but lacks the support by other manufacturers. Apple has also made AAC a format many think of as DRM only because of iTunes while MP3 is always DRM free. AAC is packed in a variety of container formats and you might see file extensions such as .mp4, .aac, .m4a or .m4b if you’ve ever had dealings with iPods. AAC compatibility isn’t that important unless your music is in this format and again you have the fact that MP3 is good enough for most uses, won’t give you trouble with DRM and have way more compatible players.
WMA is Microsoft’s main audio format and is available in both lossy and lossless variations. The lossy version is most used and with DRM stuck to it it’s often what’s sold in music stores that don’t sell MP3. WMA is second to MP3 in popularity and frankly there’s no reason to use it unless you’re using DRM’d files (which you shouldn’t).
In a response to a forum post about the Cowon D2 on another forum, an iPod fanboy once wrote that iPod supported more formats than the D2. Well, when a company makes their own proprietary audio formats that only their own players can use, sure you can add a lot of funny formats to your specs list. Apple Lossless is for the iPod what FLAC is for other players. Unless you plan on using an iPod forever, it’s not really a format you need to worry about.
Monkey’s Audio, aka APE, is a lossless format that is supported by a very small number of players. It’s not really that useful when you have FLAC and it’s rather buggy and incompatible even with compatible players.
Audible is a format used by – you guessed it – Audible. For those that don’t know what Audible is, it’s an audio book website that allows you to buy audio books and listen to them on an MP3 player. Their website has a list of compatible players and manufacturers also tend to advertise Audible compatibility. Audible uses 4 different formats depending on quality and most (if not all) new MP3 players with Audible support can play back the highest quality Audible files.
The point of this article is solely to explain the basics of audio formats on a consumer level so people will know what it means when manufacturers list compatibility with this and that format. To bottom line it all however, most people won’t ever need a format besides MP3. Lossless formats are only useful for audiophiles (or as a master copy of your music on the computer) and other lossy formats are only useful if your music is already in that format or for people that (think they) hear a difference between the codecs. Speaking to the common consumer, my advice is to stick with MP3. It’s not best, but it’s th
e most used format and it’s more than capable of delivering the quality that most people need. Having done tests on the subject, people can’t tell the difference between bitrates let alone audio formats. When it comes to portable audio, the headphones will matter the most, the player used will come second and music format will come third – as long as you’re not using 64kbps files.