The function of the Creek OBH-22 passive pre-amplifier is to provide
input selection and volume adjustment to a Hi-Fi system from an
armchair, via infra-red remote control. The unit can also be controlled
directly from the front panel.
The OBH-22 consists of a high quality motorised volume potentiometer,
and two stereo relays which select the desired input plus tape output,
together with a muting relay that can short the signals to ground.
A
built-in micro-controller decodes the infra-red signals transmitted by
the handset and translates them into commands which activate the
motorised potentiometer and the muting and input selection relays.
After each operation, the micro-controller turns itself off to avoid any
possibility of interfering with the main music signal.
LED’s are used to indicate the status and mode of operation.
The OBH-22 is purely passive and does not introduce any gain or
distortion into the signal path. It is therefore suitable to be used as
a control pre-amplifier, provided the sensitivity of the power amplifier
that is being used is high enough to be driven directly from the source.
i.e. CD player or tuner etc.
The volume control can be operated manually at any time, whether the
OBH-22 is powered or not, but without power only Line 1 can be utilised.
