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Using the headphones
CX 120BT | 9
Using the headphones
Information on the rechargeable battery
and the charging process
The headphones have a built-in rechargeable battery. A complete
charging cycle takes approx. 1.5 hours.
Before using the headphones
for the first time, charge the rechargeable battery for a complete
charging cycle without interruption.
When the headphones are being charged, the LED lights up (
>
5).
Sennheiser recommends using the supplied USB cable and a com-
patible standard USB power supply for charging the headphones.
Charging the headphones' rechargeable
battery
1. Connect the micro-USB connector of the USB cable to the micro-USB
socket of the headphones.
2. Connect the USB-A connector to a corresponding socket of a USB
power source (to be ordered separately). Make sure that the USB
power source is connected to the power supply system.
The charging process of the headphones begins. The LED displays
the charge status:
Connecting the headphones to a
Bluetooth device
To be able to use the Bluetooth wireless connection, you must regis-
ter both devices (headphones and e.g. smartphone) via the device
settings of your smartphone. This process is called pairing.
If operation differs from the steps mentioned, also refer to the
instruction manual of the Bluetooth device you are using.
LED
Meaning
lights up red
Rechargeable battery is being charged
lights up blue
Rechargeable battery is fully charged
USB-A
Micro-USB
1,5 HRS