![background image](http://html1.mh-extra.com/html/sennheiser/hdc-451/hdc-451_instruction-manual_1240590004.webp)
9
ON/OFF
LED
NoiseGard
®
mobile
HDC 451
The first „open-air“ stereo headphone with
NoiseGard
®
active noise compensation
At just 110 g, this „open-air“ stereo headphone with active noise compensation is
extremely light and provides excellent wearer comfort. Sound coupling to the ear
is directly on the ear.
왘
When you are wearing the
NoiseGard
®
mobile
HDC 451 you will still be able
to join in conversation - the voice of the person talking to you is scarcely
changed, since the speech frequency is practically unaffected by compensation.
왘
Warning or emergency signals remain audible.
왘
Understanding speech is even improved by
NoiseGard
®
, as „upward-masking“
by low-frequency sound is eliminated.
Switching on/off
ON/OFF switch for the power supply to the compensation electronics is situated
on the battery box. A green LED lights up as a check.
If the power supply is switched off or the batteries are worn out, the headphone
can still be used as a normal headphone
without noise compensation
.
Inserting the batteries in the power supply unit