4
Protective Circuit
There is one protective circuit in the LS which protects the headphones
from DC offset.
The protective circuit is triggered if either or both channels exhibit an
average DC voltage above the set threshold. If this happens the LED
will turn to Red and the amplifier will be in protection mode and will
not operate. In normal operation, when the issue is relieved, the LED
will return to its white condition indicating that the amp is ready for
operation again. If the LED stays red, please contact Monoprice Tech
Support Associates
Sometimes the protection circuit will trip when you insert or remove
the TRS plug with the amp delivering power to the jack. This means that
the amp is responding to the well-known channel shorting that occurs
during the insertion/removal of the plug. To prevent this, always turn
down the volume before removal/insertion of a TRS plug.
Preamp Output
The preamp out has an output impedance of 150 ohms. Remember that
the LS is a small power amplifier. DO NOT short the preamp outputs to
ground as this make cause damage to the amplifier.
General Best Practices
• Plug in headphone cables when the amplifier is turned off.
• Turn the volume all the way down before plugging in headphones.
• Turn the volume all the way down before putting on headphones.
• Plug in sources when the amplifier is turned off and turn the amplifier
off to switch sources.
