A direct input hearing aid is one which has some form of connection for connecting an audio input into the hearing aid.

For BTE (Behind The Ear) or post aural hearing aids the usual direct input method is using a connecting 'shoe' (or as the Americans call it 'boot'). The hearing aid has electrical input contact pads and the direct input shoe has matching sprung contacts. In the base of the shoe is 3 pin socket which accepts a 3 pin polarised plug - commonly referred to as a 3 pin Euro plug.

Methods of direct input connection varies greatly. Some hearing aids have 'gold' contacts on a side of the hearing aid, some hearing aids have very small socket contacts which accept pins in the shoe and some hearing aids have their direct input contacts hidden under a flap. Looking at the contacts are on the shoe usually gives a good clue but the failsafe route is to look in the hearing aid instructions and/or ask the audiologist who fitted your hearing aid.

The original design intent from many years ago (before radio aids existed) was to facilitate the use of a remote microphone. In practice now it is rare to use a wired microphone with a hearing aid and direct input is now usually associated with radio aid use.

A particularly good use for direct input is to allow enhanced listening for hearing aid users of personal listening equipment such as iPods, cd players, radios, computers etc..