MP3 player reviews: Features explained
MP3 player storage capacity
There are two types of MP3 player and MP4 players – hard disk and solid state.
Larger capacity players use a hard disk for storage, much like a PC does.
They tend to be bulkier than solid-state players, but you can fit more music on to them.
Solid-state players get their name because they have no moving parts.
This means the players can be incredibly small and light, but in many cases you can't store a huge number of songs on them.
To work out the storage capacity of your player, you'll need to consider that a typical pop track recorded at a decent quality uses about 4.5MB of memory, so a 1GB MP3 player, for example, could fit around 220 songs.
Radio
Some MP3 players have an FM radio, handy for catching the news or the football scores when you are on the go. And in many cases you can also record from the built-in radio.
For pocket digital radios, see the Which? digital radio reviews.
Colour screens
A nice big colour screen means that, in addition to watching video or viewing photos, you can see your track listings in colour and look at album covers.
You might be able to view photos and videos on a player, but that won't be much good if the screen size is too small, so ask for a demonstration in-store if this interests you. Players with screens of a couple of centimetres square don’t fare well in our video tests – they are just too small to watch video properly.
Battery life
Most models come with rechargeable batteries, which means you don’t have to keep shelling out on replacements when they run out.
Solid-state players typically last longer, providing on average just over 21 hours of playback per charge. Hard-disk players with a larger memory last for an average of around 16.5 hours.
Charging takes on average three hours, but some of the players with a larger memory capacity can take over four hours. With most models, you can recharge the batteries without removing them.
Audio and video formats
Digital music is available in different formats, MP3 is simply the best known and most flexible. You can play MP3 files on most players and copy them as many times as you like. Other common formats include:
- AAC A file format used by Apple (Atrac3 is Sony's format).
- WMA A Microsoft format, compatible with Windows Media Player, which is becoming increasingly widespread. WAV is the default format for audio files on Windows PCs.
- Flac and Ogg Free open-source formats.
Take care when you buy music from an online retailer – all players don't play all formats. For example, an iPod won’t be able to play music from the Sony Connect site in Atrac3 format.
Like MP3, MP4 is simply the name of a type of computer file, but for video rather than music.
The most common video formats are DivX, Xvid, Mpeg and Real Video.
- DivX Among the most popular formats because it can compress lengthy video segments into small sizes while maintaining relatively high quality.
- Xvid DivX’s main competitor. But where DivX is proprietary software, Xvid is free and open source, and can be used on many operating systems.
- Mpeg The Moving Picture Experts Group has standardised compression formats. Mpeg-1 was the initial compression standard, Mpeg-4 expands on this with low bit-rate encoding and digital rights management (DRM).
- WMV Windows Media Video is a generic name for video technologies developed by Microsoft, part of the Microsoft Windows Media framework.
- Mov The QuickTime Movie file format was developed by Apple. All Apple systems ship with QuickTime already installed and it is optional for Windows systems.
- Real video This proprietary video format, developed by RealNetworks, is supported on many platforms, including Windows, Mac, Linux, Solaris, and several mobile phones.
Again, be sure that the file format is compatible with your player (or can be converted using supplied software) before buying any content.
Connections
You connect your MP3 or MP4 player to a computer via either a USB or a Firewire connection.
A Firewire connection will transfer music at about twice the speed of a standard USB connection. However, most new players are supplied with the newer USB 2.0 standard, which is almost the same speed as Firewire.
Some MP4 players let you record directly to them. All you will need is the right sort of lead to connect the player to your chosen source.
Clock
Many players have a clock and alarm, so your MP3 or MP4 player can double as an alarm clock on holiday.
Accessories
Some MP3 players come with a belt clip, neck strap or arm band, all helpful for carrying the player on the go and particularly useful if you run with it. With other MP3 players these items are available but are sold separately.
Headphones
If you buy only one accessory, make it some new headphones. The sound quality of supplied headphones varies between models but, apart from the very best, it is normally nothing to get excited about.
However, our listening tests reveal the importance of a good pair of headphones. Our test panel used each player with the default headphones, and also a pair of high-quality Beyerdynamic DT770 Pro headphones.
The result? Almost every model scores top audio-quality marks when using the Beyerdynamic headphones. The Beyerdynamic headphones cost around £90, but if that seems a bit steep, a pair of light and compact Which? Best Buy Sennheiser PX100s will set you back only £30.
Hi-fi cables
For around £10, you can buy a cable that connects the headphones socket on the player to an input socket, usually the aux socket, on your home hi-fi system.
Speaker docks
These mini speaker systems may not carry the same punch as a connection to your hi-fi system, but they are a compact and portable option for the seasoned traveller. We have more than 30 speaker dock reviews on Which.co.uk.
Charging leads
Most players’ batteries are charged when connected to a computer via the supplied USB cable. For charging via the mains, a separate adaptor cable has to be purchased. An iPod mains charger, for example, costs around £15.