THE BEAUTY OF POWER
B-52 US Series Professional Power Amplifiers - Instruction Manual
US SERIES AMPLIFIERS
is not referenced to the ground. In this mode the chan-
nel 2 input is inactive.
NOTe:
See the CONNECTIONS section later in
this manual for more details on PARALLEL
MONO and BRIDGED MONO modes.
WARNINg:
DO NOT change settings of the
BRIDGE / STEREO / PARALLEL switch when
amplifier is ON. Always turn amplifier OFF and
connect output cables and input cables appro-
priately first, then set the switch in desired
position BEFORE turning amplifier back ON.
WARNINg:
DO NOT change settings of the
BRIDGE / STEREO / PARALLEL switch when
amplifier is ON. Always turn amplifier OFF and
connect output cables and input cables
appropriately first, then set the switch in desired
position BEFORE turning amplifier back ON.
7. BINdINg POST OUTPUTS
Use the binding posts to connect your loudspeakers
to the amplifier. Binding posts are a good option for
fixed installations or when you do not have Speakon
fitted speaker cables. The high-quality insulated bind-
ing posts offer a variety of connection options. Use
speaker wires with stripped ends (do not strip them
more than ½” or 12.5mm), using the holes on the
bottom of the binding posts. Ensure that no part of
the speaker wire is exposed when connected to the
binding posts. Alternatively, you can also use speaker
cables terminated with standard banana plugs. Make
sure that no part of speaker wire or banana plugs are
exposed when connected to the binding posts.
NOTe:
US-Series amplifiers configured for use
in Europe are provided with permanent plastic
inserts which prevent using banana plugs for
speaker connection. This is a safety measure
required by European safety laws.
NOTe:
In the BRIDGED mode, the loudspeaker
must be connected using the two red binding
posts. The positive (+) wire from the loudspeaker
must be connected to the Channel 1 red post,
and negative (-) wire from the loudspeaker must
be connected to the Channel 2 red post, as
indicated on the rear panel just below the
binding posts.
WARNINg:
NEVER CONNECT speakers with
an impedance lower than the rated minimum
impedance of the amplifier. The lowest
impedance in STEREO and PARALLEL modes is
2 Ohms for each channel. The lowest impedance
in BRIDGED mode is 4 Ohms. NEVER
CONNECT 2 Ohms rated loudspeaker(s) or
a combination of speakers to the amplifier in
the BRIDGED mode.
NOTe:
Refer to the CONNECTIONS section
later in this manual for speaker wire connection
diagrams.
8. SPeAkON™ OUTPUT CONNeCTORS
Use these speaker outputs to connect cables fitted with
Speakon™ cable connectors. US-Series amplifiers
have two connectors, one for each channel, to con-
nect Speakon™ fitted cables. The 1- pin is connected
to the ground. The 1+ pin is connected to the output
of each channel, which is an industry standard.
You can connect both channel 1 and channel
2 loudspeakers to the Channel 1 output connector.
To do this a quad speaker cable must be used. The
Channel 1 speaker should be connected to pins
1-/1+ and the Channel 2 loudspeaker is connected to
pins 2-/2+.
You can use the Channel 1 output connector for
BRIDGE connection of your loudspeakers (when the
amplifier is in BRIDGE mode). In this configuration the
loudspeakers connected must use the 2+ pin of the
connector for the loudspeaker’s ground connection
(NOT CONNECTED TO THE GROUND OF AMPLI-
FIER) and pin 1+ for the speaker’s HOT connection.
NOTe:
Match the pin designations printed next
to the output connectors on rear panel to ensure
proper connections.
9. CIRCUIT BReAkeR
The circuit breaker protects the amplifier from faults
at the AC supply and serves as protection when the
amplifier fails. If the circuit breaker trips, cutting AC
power supply to your amplifier, it may indicate a seri-
ous malfunction or failure. Wait for the circuit breaker
to cool before resetting it by simply pressing the reset
knob. If the circuit breaker repeatedly trips, especially
when there is no signal on the inputs or outputs, this
indicates a failure of your amplifier. DISCONNECT
the power cord from the wall AC outlet immediately
REAR PANEL CONTROLS (cont.)
12
