Features Installation and Operation

Features		Installation and Operation

MAINS POWER INLET / FUSE DRAWER

A combined mains power inlet with integrated fuse drawer is situated on the rear panel.

POWER ON INDICATOR

A blue LED on the front panel indicates when the unit is operating. The LED will flash for 30 seconds when power is turned on. During this time the servo circuitry is stabilising and no audio will be issued from the bass drivers.

OVERLOAD PROTECTION

Voltage clamps on the balanced amplifier input protect the 328A from accidental overdrive or spikes while allowing excellent working headroom.

The amplifiers and power supplies are individually protected from overload. If a protection circuit operates, the associated driver will cease operation until the circuit automatically resets. Thermal and current protection is used on the power supplies, while the amplifiers incorporate thermal overload protection.

MOUNTING RECOMMENDATIONS

The most suitable position to mount the monitor is on a stand behind the mixing console. Any stand used must be able to carry the 45 kg weight of the monitor.

To help ensure safe operation it is important to consider stability when mounting the monitor on a stand. There are two methods of stand-mounting a 328A:

a)Placing directly on the stand platform (normally rubber covered). The illustration below shows the location of the centre of gravity (C of G) of the monitor to help you position the 328A safely. The C of G should fall as close to the centre of the platform as possible.

b)Fixing the four rubber adhesive-backed feet to the base of the monitor and placing it on the stand platform. The feet should be positioned surrounding the C of G and as far from it as the platform size allows. (See the illustration below for a suggested placement.)

337337

BALANCED

AUDIO IN

SPEAKER SENSITIVITY

4dBu			10dBV
4dBu			10dBV


	TREBLE SHELF
1.5dB		0dB	1.5dB
1.5dB		0dB	1.5dB

BASS ROLL-ON

19Hz 50Hz 100Hz

POWER

OFF

VOLTAGE RANGE 100-120V 50-60Hz 220-240V 50-60Hz

REPLACE WITH FUSE:

BUSSMAN S506-10A 250V. POWER CONSUMPTION 3kW

CONTROLS

The user controls described below

are mounted on the rear panel of

the 328A.

Balanced Audio In

Accepts the output from an audio

signal source via an XLR

connector or 1/4” jack. The signal

can be balanced or unbalanced

(see Connecting the Audio Input).

Speaker Sensitivity

Switches the input sensitivity of the 328A monitor to either +4 dBu or -10 dBV as required.

Treble Shelf

Provides a 1.5 dB boost or cut adjustment to the HF response of the 328A if required.

Bass Roll-on

Applies a 12 dB / octave roll-on (at three preset frequencies) to the LF response of the 328A if required.

132

140

245

210

C of G

Positioning the feet relative to the C of G

CONNECTING THE AUDIO INPUT

The 328A’s combined XLR / 1/4” 3-pole input connector is wired to the balanced amplifier input as shown in the table below:

	XLR input	Jack input
Signal (+)	Pin 2	Tip

Signal (-)	Pin 3	Ring

Ground	Pin 1	Screen

If the source itself has a balanced output, use twin- conductor shielded cable (microphone cable) connecting Pin 2/Tip to Pin 2/Tip, Pin 3/Ring to Pin 3/ Ring,

and Pin 1/Screen to Pin 1/Screen (using the shield).

If the source has an unbalanced output, use single conductor shielded cable with Pin 2/Tip of the input connected to the ‘hot’ signal pin of the source, and Pins 3/Ring and Pin 1/Screen linked together and connected to the source signal ground.

3	English