MP3 Speakers

MP3 players are fantastic. All people (well... most people) love their own style of music and to be able to take music around wherever you go can be quite comforting - not to mention entertaining (imagine sitting through a train ride or long flight these days without some form of portable music to entertain you).

The devices have become smaller and smaller, and their storage capacity bigger and bigger. You can literally fit days worth of music on the newer iPods. However, sometimes when you're not on the move, you want to listen to the music on your portable device without the hassle of earphones. This is where an mp3 speakers can be a great idea.

In line with the rise of mp3 players, there are now multiple brands and styles of speakers for mp3 players. The type you choose really depends on what you'll be using them for, but here is a little basic advice.

Firstly, you need to check what kind of output your mp3 player has – this is really important because they don't all have the same connector.  The vast majority just have a standard 3.5mm jack (that's the type of plug that you'd expect to see on earphones).  The major exception to this is the iPod and iPhone (in fact anything by Apple).  Apple always have to do things a little bit differently to the rest of the world and they often also have a proprietary connector on their equipment. 

This means that, if you want to, you can buy speakers that are specifically made for the iPod; the benefit being that most of these types of speakers will also charge the iPod's battery if the speakers are connected to the power (as if they were an mp3 speaker dock).  However, always check which models of iPod the speakers are designed for – just because it's compatible with an iPod, there's no guarantee it'll be compatible with your model of iPod – this can be very annoying!

• Inexpensive portable mp3 speakers: These are simply so you can take the earphones out and still listen to your music when you're on the move. (You know the type - if you've ever taken public transport, you'll have heard some kid playing their “music” through them for the whole train to hear.) In honesty, the quality isn't great; the sound is usually slightly trebley, and the volume won't go incredibly loud without the sound distorting. However, increasingly, the quality is getting better and better, and if all you want them for is to occasionally listen to music when you're out of the house without earphones, these are the style to go for. They can often cost less than £20.
• Bookshelf and Small Desk Speakers – It's fairly obvious what these are. They're certainly larger than the inexpensive and portable variety, and this translates into a better quality of sound. In fact a lot of these types also have a sub-woofer and two standard speakers to really improve the bass and overall sound quality. If you don't need to move them around a lot, and don't need excessively good sound quality, consider buying a cheaper (less than £50) set of desk speakers. MP3 music is compressed and this means that some of the sound quality is lost. In my (and possibly a lot of other people's opinion), it's really not worth buying the super-high-end brands of speaker if you'll only be using them with a portable mp3 player.
• Having said this, you may still decide to purchase the higher-end mp3 player speakers or even a full mp3 speaker system. It's up to you how much to compress an mp3 track, and when you're ripping your CDs, you can leave the tracks at very high quality (which clearly increases the size of the file; however, with modern iPods and mp3 players, their storage capacity is so big that this may not matter). So if you do choose the more expensive range of speakers, their increased performance can highlight any loss of quality on the compressed mp3 file. This is why it's sometimes better to leave the quality settings high when using speakers for mp3 instead of earphones. If you're going to invest in a high-end set, you might also consider looking into in wall speakers or similar.

So what is audio compression? Well, because anything digital has its data stored in binary (which is represented by discrete values of 1 and 0 or on and off, rather than an analogue signal), the sound isn't actually fully recorded. Instead, what happens is that the sound is recorded at set points over and over. Because there are so many (1000s per second) of these specific parts of the sound recorded, when it's played back, our brains don't realise that it was recorded in this way. Imagine a TV picture, which has a frame rate of 25 frames per second. The picture isn't actually moving – there are 25 still images that change slightly and when they displayed quickly in a sequence our brain is fooled into seeing them as a moving image. The same is true of digital audio.

What an mp3 encoder does is take the digital audio and, instead of keeping all of the data as it is, the encoder cleverly uses mathematical algorithms to store only some of the data, but store it in a way that most of the missing data can be re-built when it's played back.  The algorithm will process the audio differently for different types of audio.  For example, electro acoustic guitars produce audio that will be compressed in a slightly different way than piano music.  The lower the bit rate when the music is compressed, the more actual data needs to be re-built later on and the more inaccurate this process is; this leads to lower quality audio.

What does this means in terms of storage space?

A standard compressed mp3 file will often be recorded at 128 kbps – this means that you can fit over 17 hours of music into 1 GB of space.

If you were to compress at 256 kbps, you'll get just under 9 hours into 1GB.

And if you're compressing to the maximum standard bitrate of 320 kbps, you'll still get about 7 hours into 1 GB of space. This means that, even if you set the quality to the high 320 kbps bitrate so you can really make use of that high-end mp3 speaker, an 8 GB mp3 player (for example), will still fit 56 hours of music.