A Brief Guide To Understanding Earphone Specifications

 

As we frequently get asked about what the various specifications mean and how they affect a set of earphones, we thought it would be helpful to pop you through a quick guide with a few simple answers to further explain all the information we list for each set of earphone.

Cord

Exactly as you’d expect, this refers to the length and type of cable on the earphones/headphones in question. Obviously, this doesn’t apply to wireless or Bluetooth headsets!

Driver Unit

This refers to not only the type of driver unit held inside each set, but the number of drivers within each earphone too. Many people feel that multiple drivers offer better sound reproduction, as with these each driver is designed to target a specific frequency range, whereas a single driver has to handle the full hearing spectrum.

The sizes and types of drivers affect not only the frequency response (for example larger sized drivers tend to offer more depth in bass frequencies), but the detail and clarity of the sound too. Multiple drivers can therefore in some cases mean more depth and clarity and balance overall.

Ear Coupling

This refers to the type of fit, which is how they sit on or in the ears. ‘Earbuds’ sit just inside the ear and so therefore do not allow for much ‘blocking-out’ of background noise. Most sets bundled with MP3 players will be earbuds.

Intra-aural earphones sit inside the ear canal and therefore usually come with interchangeable silicon and foam tips to allow you to get the best seal. A better seal means you not only experience the full potential of the earphones (as much detail and bass etc as intended), but also means more isolation of background noise. Most manufacturers suggest that a good, tight seal can allow for up to 90% of ambient noise isolation.

Supra-aural headphones tend to be a little smaller and sit on the ear, as opposed to encompassing the full ear in the way that circum-aural sets do. Both supra-aural and circum-aural can be either open or closed back. Generally speaking, open-backed headphones allow for a wider-soundstage and therefore a more ‘natural’ sound, some would argue. Their open design does mean that they do not block out much ambient noise, and also that noise-leakage levels are quite high, making them less suitable for use in public places where other people may be disturbed by the noise leakage. Closed-back headphones have semi-airtight cups that provide excellent isolation background noise. This makes them ideal for studio monitoring and/or DJ use. A closed-back design also means there is far less noise leakage, making them a little more suitable for use commuting, or in an office for example.

Frequency Response

Frequency response is measured in Hertz (Hz) – one Hertz is one cycle per second. This is an important factor to take into account as it refers to the frequencies that can be reproduced by the earphones in question. Earphones with a wider frequency response can physically reproduce more high and low tones, and generally speaking, a wider frequency response means the sound will be fuller and more accurate –of course you want to hear the tracks as recorded originally, as they were intended to be. Broadly speaking, the average human hearing range is between 20Hz – 20kHz, and so whilst some of the tones reproduced may be technically inaudible, you will notice if they are not there, for example in earphones with a narrower frequency response.

Impedance

The resistance of the headphones/earphones measured in Ohms. The greater the impedance, the more ‘energy’ needed to power the headphones. Sets with lower impedance will sound quieter than those with higher impedance because of the power needed to power them. Whilst lower impedance headphones are generally more efficient, meaning you will get more volume and playing time from them, just remember that other factors, such as power output, will affect the volume, and so it is often advised that the impedance of the headphones used match the audio device being used. Most portable media/audio players suggest the maximum impedance for headphones should be 64 Ohms.

Input Connection

This indicates the size and type of ‘jack plug’. Most music players have a 3.5mm headphone socket, which is the standard size. This also details whether or not the connection is straight, or right-angled.

Manufacturer’s Warranty

Whilst we are confident in the quality of our products, unfortunately from time to time, things can go wrong. This section indicates the time period of the limited warranty supplied by the manufacturer.

Maximum Power Input

This is the maximum power a set of earphones can take before being damaged, and the circuitry being physically overloaded. This is something that is quite often only applicable when dealing with players that have a huge output, for example the Cowon D2 with its 74mW amp.  It should be noted though, that when exposed to an input higher than recommended, the earphones won’t just blow automatically, and there will be a safety margin built-in by the manufacturer. I’d not advise testing this one at home anyway, blown ear-drums or permanently damaged hearing is something you’d probably wish to avoid…

Microphone

In the age of music phones, many people require the option to switch seamlessly between calls and music. This section details the sensitivity of the microphone (where applicable, usually built into the cable of the earphones). Generally speaking, the higher the sensitivity, the more the microphone will pick up, which affects how far away from your mouth the microphone can be whilst you speak etc.

Noise Isolation

On our website, this is defined as an estimated optimum percentage of background/ambient noise. This is because this depends on the fit or seal of the set in question, and the environment in which they are being used.

Noise cancelling headphones are an entirely different kettle of fish. These earphones have special technology built-in, meaning tiny microphones pick up the surrounding noise, and then the special circuitry actively generates an identical out-of-phase signal that when played back, helps cancel out external noise.

Sensitivity

This is a function of impedance and the relationship of the headphone output and the source material. To put it most simply, the better the sensitivity, the less power from the headphone amplifier is required to hear the smallest noise.

Weight

The weight in grams of the earphones/headphones (not including the cable)

Final Notes

Please bear in mind, that two different sets of headphones with similar specifications will probably sound entirely different, and that build-materials, tuning of the ear cushion tips, construction etc will all have an impact on the sound reproduction. Numbers may tell you one thing, but only your ears will really know which are best for you!

 

iTunes: How to convert a song to a different file format

 

With iTunes being a very popular source for purchasing music it is worth noting that not all MP3 players can use iTunes (.m4a) music files directly. However, you can use iTunes to convert the songs to the standard MP3 format. Here’s a quick guide on how to do that from Apple’s website:

 

Using iTunes you can convert a song to a different file format while keeping a copy of the original. For example, you can save a copy of an uncompressed song file such as AIFF or WAV to a compressed format like MP3, AAC, or Apple Lossless Encoder.

 

Saving a copy of a song in a new file format

 

When converting from a compressed to uncompressed file format (for example, from MP3 to AIFF) you shouldn’t notice any reduction in sound quality. However, when converting between compressed formats (for example MP3 and AAC), you may notice a reduction in the sound quality. For the best results, if you want your music encoded in a different file format, you should import the music again from the original source using the new encoding format.

 

To convert a song’s file format:

 

1)  Open iTunes Preferences.

Windows: Choose Edit > Preferences.
Mac: Choose iTunes > Preferences.

2) Click the General button, then click the Importing Settings button in the second section of the window.

3) From the Import Using pop-up menu, choose the encoding format that you want to convert the song to, then click OK to save the settings.

4) Select one or more songs in your library, then from the Advanced menu, choose one of the following (the menu item changes to show what’s selected in your Importing preferences):

- Create MP3 version

- Create AAC version

- Create AIFF version

- Create WAV version

- Create Apple Lossless version

 

If you haven’t imported some songs into iTunes yet, you can import and convert them at the same time. This will create a converted copy of the file in your iTunes Library based on your iTunes preferences. To convert all the songs in a folder or on a disk, hold down the Option key (Mac) or Shift key (Windows) and choose Advanced > Convert Import preference setting. The Import preference setting will match what you chose in step 3. iTunes will prompt you for the location of the folder or disk you want to import and convert. All the songs in the folder or on the disk will be converted. Note: Some purchased songs are encoded using a protected AAC format that prevents them from being converted. iTunes Plus purchases are not protected and can be converted.

 

The song in its original format and the newly converted song appear in your library.

 

Additional Information about compression

When you convert a song, some data may be lost due to the way certain formats compress data. For this reason these formats are sometimes called “lossy” formats. The advantage of using a “lossy” format is that the file sizes are much smaller, which means you can store more songs in the same amount of disk space. The disadvantage is that the sound quality may not be as good as the original, uncompressed format. Depending on the song, the speakers or headphones, and the player you use to play the song, you may not be able to tell the difference between a compressed “lossy” song and a song that is not compressed.

 

Once a song is compressed (meaning some of its data is lost) you cannot retrieve the data by uncompressing it. If you convert a song from a “lossy” format to a uncompressed format, the quality of the song will not improve and the file will only take up more disk space. For example, if you convert a song in MP3 format (a compressed format) to AIFF (an uncompressed format) the song will take up much more space on the hard disk, but it will still sound the same as the compressed file. In order to take advantage of uncompressed formats you should only import songs using these formats.

Questions And Answers

We get quite a varied range of questions via our Technical Support phone line, and we’re more than happy to help where we can. We’ll feature some of the more regular questions in this newsletter in case any of the answers are of interest.

Hi, my Cowon J3 is rated for 64 hours of playback but I am experiencing a bit less when playing back my music, is this a fault with my player?

This is a question we get a lot and for the majority of cases it wouldn’t be a fault with the player. The time the player’s battery will last will depend on how the player is being used so all manufacturer’s will make a battery test with the player carrying out a specific task.

Cowon for example use the following settings when they measure the battery life of their players:

- Volume 15

- Standard earphones

- Playback of a 128kbps MP3 file

- No BBE+ or Equaliser settings

- Screen off

If you are using other settings then the battery life will be different. If you have a higher volume, or driving different earphones then the built in audio amplifier will be using more power which will reduce the battery life, likewise if the screen is always on this too will require power.

Using higher bit rate music files and using equaliser / BBE+ effects will also require further power by the main processor in the player due to all the extra calculations required for processing the music which will also reduce battery life.

Will the Speedo Aquabeat waterproof earphones connect to my iPod?

This is a question we get occasionally, for using a normal MP3 player in a swimming pool and in a sauna.

While the Speedo Aquabeat waterproof earphones do have a standard 3.5mm stereo jack it can connect to the headphone port on Apple iPods and other MP3 Players, although do remember that most players are not waterproof and we would advise not to use them in a pool or sauna.

For waterproof players for swimming take a look at the Speedo Aquabeat (available in 1GB, 2GB and 4GB memory sizes and in a variety of colours), the NU Dolphin Touch  (available with 4GB memory) or the Finis SwiMP3 which uses a novel ‘bone conduction’ method of audio playback rather than relying on in ear earphones. All of these players are fully waterproof and specifically designed for swimming.

However, we would not recommend any MP3 player for use in a hot sauna. The heat and humidity would be likely to cause damage to the player.

Help! My Speedo Aquabeat isn’t playing my iTunes music.

This is still a common problem we have reported to us by customers, that the Speedo Aquabeat doesn’t play iTunes music and doesn’t even turn on.

It’s all down to the file formats of music that the Speedo Aquabeat can support – which are only MP3 and WMA (not DRM protected). Copying other types of files, such as iTunes .m4a music files, will result in the player not starting up to play music. Please ensure only MP3 and WMA (not DRM protected) files are copied across to the player.