Sennheiser HE 1 User Manual page 52

If a problem occurs ...
50
High-voltage protection
In order to best protect you, the high voltage of the electrostatic headphones
and tube headphone amplifier is permanently monitored at the transducers,
cables and connections. If irregular values are observed, the high-voltage
protection is activated immediately and the voltage is cut off. The status LED
flashes red quickly two times. In this case, the HE 1 cannot be used.
Should the high-voltage protection be activated, proceed as follows to deacti-
vate it:
Set the power switch to
▷
LED goes off (up to 30 seconds).
Make sure that there is no moisture on or in the product, that no objects
▷
touch the transducers and that the cables are in perfect condition.
Set the power switch to
▷
It might be that the operating elements retract to the "off" position.
Press the on/off button.
▷
The HE 1 switches on normally.
If the high-voltage protection is still activated, please contact your Sennheiser
partner (see "Contact" on page 4).
OFF to switch the HE 1 off and wait until the status
ON to switch the HE 1 on again.