Aurex HR-E7

Commentary

Condenser type stereo headphone with improved efficiency of back electret system.

Uses back electret (back electrode electret) system.
In this method, since the diaphragm and the electret are separated, the efficiency of the electret itself can be increased. Moreover, by making the diaphragm thin, the vibration mass can be sufficiently reduced.
In the HR-E7, a newly developed high-voltage electret (a special polymer film bonded to a metal plate) is electrically connected to the diaphragm through high resistance, realizing stable operation of the diaphragm.

The diaphragm is made of polyester film with evaporated aluminum and has a diameter of 51 mm, a thickness of 4 microns and a mass of 11 mg.

The impedance selector switch is incorporated in the middle of the cable and switches between two positions.
The impedance matching transformer is built into the headphone body.

Model Rating

Type	Electret condenser headphone
Headphone Section
Drive system	Push-pull full face drive
Capacitance	60pF
Diaphragm	4 micron thick polyester film diameter 51 mm Aluminum double-sided deposition
Frequency characteristic	20 Hz to 20 kHz
Output sound pressure level	101B/3V (AMP position)
Maximum sound pressure level	115dB
Harmonic distortion factor	0.5% (at 400 Hz standard input)
Ear pad pressure	300g (Ear Spacing 150 mm)
Code	4-wire 2.5m with stereo plug Vinyl cord
Weight	285g (cord not included)
<Adapter part>
Format	Input impedance switching type
Input impedance	For Amp : 500 Ω For Deck : 8 Ω