Interface Headset

File:InterfaceHeadsetExample.jpg

The three Eva pilots with each of their interface headsets; note that Rei has taken hers off and is holding the tiara

An Interface Headset is a small device worn on an Evangelion pilot's head, which is the primary means by which a pilot controls an Eva Unit. It does this by linking with the cranial nerves of the pilot, thus allowing the pilot to "synchronize" with the Eva and control its movements.

Interface Headsets are usually worn in conjunction with a Plug suit, however Plug suits do not appear to be absolutely required to pilot an Eva, as there are several occasions when there was no time and the pilot just hurried into the Eva without one, but an interface headset has almost always been worn every time someone has piloted an Eva. However, the sole exceptions to this rule appear to be during the simulation plug test in Episode 13 and Shinji Ikari not wearing his headset during The End of Evangelion. Both the plugsuit and the headset appear to greatly increase a pilot's ability to synchronize with an Eva, and the headset aids much more than the suit, but conceivably a pilot could synch without them.

Interface headsets give the appearance of being two small plastic devices placed on top of the head, one on either side. The interface headset is actually one object: a thin wire "tiara" links the two larger pieces atop the head. The wire section is nestled beneath the pilot's hair and thus always obscured from view, making it appear as if the headset is comprised of two separate devices placed on top of the head.

Asuka Langley Soryu near-constantly wears her Interface Headset, at home and while at school, because she is proud of her status as an Eva pilot and wants the whole world to know that she pilots an Evangelion.

It apparently doesn't matter what part of the head the devices on the Interface Headset are worn: Rei and Shinji's are worn near the front of their head, but Asuka apparently wears the tiara backwards, so that the plastic devices on it are near the back of her head, where she has effectively incorporated them into her everyday hairstyle.

In Volume 1 of the manga adaptation of the series by Yoshiyuki Sadamoto, Sadamoto introduces the bonus materials section at the end of the volume by offering the explanation that:

"On the floor of the midbrain is the ventral tegmental system, that neurobiologists call region A¹⁰. Cells soaked in dopamine, certain emotions are processed here: such as the thoughts of two lovers - or a parent and a child. And it is the synchronization of the threads and bundles of A¹⁰ that splice pilot and Eva together; to become one entity, to fight. In other words, the power of love drives this weapon of mass destruction."

Notes

• Exactly what Interface Headsets are and how they function is never explicitly elaborated upon on-screen, but is from Gainax-released background material, such as the Red Cross Book.
• Eva pilots are never seen putting on or taking off Interface Headsets during the entire series. The wire tiara which actually connects the two larger pieces and supports them in place on top of the head is hidden under their hair when worn and is only on-screen once, briefly seen floating among the contents of the Entry Plug in Episode 20 and otherwise only in behind-the-scenes production sketches. This has resulted in many fans assuming that the two plastic pieces clearly visible atop the head are somehow just "stuck" on the head, either with adhesive, by being attached like a hairclip, etc. when actually the entire thing is a single headset. As these objects were never formally named on-screen, fans frequently refer to them as "A¹⁰ nerve clips", because the description of them in the Red Cross Book says that they interact with the A¹⁰ nerve. However, script production notes (released with the Renewal of Evangelion DVDs) clearly and repeatedly refer to the object as an "Interface Headset".