User's Manual

12
at presence of a contact closure between the terminal and the ground. This contact is
convenient for situations where a separate emergency system is installed and complete
background music muting is required at occasion of a (fire) alarm. The emergency system
contact outputs can be connected to this contact input.
Bluetooth pairing button contact:
A Bluetooth pairing button contact is provided allowing connection of an optional Bluetooth
pairing button module. This way the pairing button can be integrated in a convenient location,
eliminating the need to reach out to the preamplifier in order to pair a device. The button
can be integrated to allow users to pair Bluetooth enabled devices while the preamplifier is
mounted in a locked rack or a separate room. The button and LED will operate identical to
the button and LED on the preamplifiers front panel.
The connection can be made according to this wiring diagram:
Bluetooth antenna connection:
The included Bluetooth antenna should be connected to this terminal for good signal reception.
It is connected using an SMA type connector and allows antenna extension (with an optional
extension cable) for mounting outside of closed rack cabinets.
Unbalanced stereo line inputs:
Unbalanced line level input sources (e.g. media-players, radio tuners, ...) can be connected
to line inputs channel 2 to channel 4. These standard line inputs are implemented using
RCA connectors and fitted with a gain control potentiometer whereby the input sensitivity
can be controlled within a range of +4 dB ~ -20 dB.
NOTE
The gain control potentiometers for channel 3 (mixed with Bluetooth receiver) and channel 4
(mixed with front 3.5 mm jack input) are also affecting the level for these secondary inputs.
Balanced stereo line input:
Balanced line level audio sources can be connected to channel 1 which is implemented using
2 x XLR connectors. It is fitted with a gain control potentiometer whereby the input sensitivity
can be adjusted within a range of +4 dB ~ -20 dB. A mode switch allows to switch the input
between mono and stereo mode and mixes both channels when switched to mono, making
them identically available on both output channels.