Understanding Audio Cables

Not all assistive devices are created equal, and it can be somewhat overwhelming with all the various sizes and configurations.

Here is some basic information that can help you better understand the differences and make the right choice when selecting an assistive listening accessory.

2.5mm (top)
(used with telephones)

3.5mm (bottom)
(standard size for use with 
MP3 players, PDAs, and 
assistive listening devices)


Mono plug (one ring)
Usually found on older model
accessories primarily designed 
for use with FM systems.

Stereo plug (two rings)
Newer accessory models 
use stereo plugs to be more 
compatible with MP3 players, 
PDAs, phones, and other audio devices.

Adapter 
A variety of inexpensive adapters are available at local electronics stores. These adapters convert stereo to mono plugs or 3.5mm to 2.5mm plugs (and vice-versa).

Adapters are useful when you are using accessories (audio cables, neckloops, etc.) that have a different configuration than the receiver you are connecting to.

For example, an older FM system may only work with a mono plug – and you have a stereo neckloop jack. Simply use a stereo-to-mono adapter and it should work properly.

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