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9
Technical data
Noisegard
®
mobile
HDC 451
Acoustic principle
dynamic, „open-air“
Frequency range
20 Hz - 18,000 Hz
Impedance
160 ohms
Total harmonic distortion
< 1 %
Active compensation
10 dB + in a range of 400 to 1,000 Hz
Headband pressure
approx. 1.6 N
Weight without cable
approx. 110 g
Cable
one-side only, total length 2 m
with 3.5 mm-stereo jack plug for audio signal
Power supply
2 x 1.5 V mignon (AA) alkaline-manganese
batteries or 2 x 1.2 V storage batteries
mignon (AA) 600 mAh
Operating time
approx. 80 hrs. (batteries)
approx. 20 hrs. (storage batteries)
Display
green LED as battery check
Scope of delivery
1 headphone HDC 451
1 adapter to double mono jack plug 3.5 mm
1 adapter to stereo jack plug 6.3 mm
NOTES
NoiseGard
®
mobile
helps to reduce
noise for greater comfort.
NoiseGard
®
mobile
is not a noise protection
system for medical purposes!
Listening to loud music ? - No !
Listening to music via headphones tempts
into listening to louder music than loud-
speakers would. A high volume that affects
your ears for a longer period can cause
lasting hearing defects. Protect your sound
hearing; Sennheiser headphones are good
even for low volume musical enjoyment....