There are three kinds of situations for the ear amplifier. One is the sound source used. For example, there is no earphone dedicated output jack on the CD/DVD player. At this time, a headphone amplifier can be equipped to output from the audio line of the CD/DVD player (LINE OUT). Use two signal wires to connect to the audio input jack of the amplifier.

As the name suggests, mobile phone headsets are the headsets that are used with mobile phones. Mobile phones, headsets, chargers, and data lines sold on the market are standard on mobile phones.

Mainly in the dynamic (Dynamic) and electrostatic (Electrostatic) headphones two categories, although in addition to these two categories, there are several types of magnetic, but have been eliminated or used in professional use market is very small I will not discuss it here.