to the wall with suitable screws for carrying the loudspeaker's weight of 43 kgs (95 lbs). The maximum tilt angle for the loudspeaker enclosure is ±5 degrees. Do not install the enclosure horizontally.

The mounting brackets are pre-drilled for enclosure alignment angles of -15°, 0° and +15°. If necessary, you can drill new holes to the brackets for exact loudspeaker alignment. The rubber isolators provided must be placed between the brackets and loudspeaker enclo- sure.

It is recommended that the surroundings of the loudspeaker are covered with about 10 cms (4") of rockwool or similar damping material. If the loudspeaker is covered with a cloth, it must be acoustically transparent and a free space of at least 2 cm (3/4") left between the front baffle and the cloth.The reflex port of the loudspeaker enclosure is located on the left side of the enclosure (see Figure 2). The airflow from the port must not be obstructed, and a free space of at least 5 cm (2") is required before the port.

The RAM4 amplifier is shipped with a pair of rack ears to provide fitting into a 19" rack and a set of feet for placement on a shelf or table.

Sufficient cooling for the RAM4 amplifier must be ensured. The cooling fan on the amplifier back panel draws air through the filter on the left side panel and blows the warmed air to the space behind the ampli- fier. The airflow must not be obstructed. Note also that the space behind the amplifier must either be ventilated or sufficiently large to dissipate heat so that the ambient temperature does not rise above 35 degrees Celsius (95°F).

Connections

Each loudspeaker is delivered with two Speakon 8-pole cable connectors. There is one 8-pole Speakon output marked LOUDSPEAKER CONNECTOR on the amplifier and two inputs (one on each side) on the loudspeaker enclosure. Use only one of these inputs at any time. The inputs may not be used for daisy-chaining several loudspeakers or connecting two amplifiers to a single loud- speaker. The 4-pole Speakon output (LED CONNECTOR) on the amplifier is not used with the AOW312B.

Measure the required length of 8 pole cable and secure the connectors on it pin to pin. See Table 1 below for recommended cable

thicknesses. The whole cable should have an outside diameter of 8 to 20 mm (5/16" to 13/16") to fit in the Speakon connector.

Alternatively, pre-terminated lengths of cable are available from Genelec.

Be sure not to mix the amplifier/loud- speaker pairs when installing multiple loudspeakers at the same time. Each amplifier and loudspeaker packed together are calibrated together for optimal performance and marked with the same identification number.

Before connecting up, ensure that the mains switch is off. Check that the mains voltage selector on the amplifier back panel is correctly set to your local voltage. Audio input is made via a 10 kOhm balanced XLR connector, but unbalanced leads may be used as long as pin 3 is grounded to pin 1 of the XLR (see Figure 7). Once connection has been made, the loudspeakers are ready to be powered-up.

Access to the

front panel controls

The decorative front panel of the RAM4 amplifier is held in place by guide pins and two magnets. To remove the panel, pull it straight out.

Setting the input sensitivity

Adjustment of the input sensitivity of each RAM4 amplifier can be made to match the output of the decoder or other source, by use of the input sensitivity control on the amplifier front panel. A small screwdriver is needed for the adjustment. The manufacturer default setting for this control is -6 dBu (fully clockwise) which gives an SPL of 100 dB @1m with a -6 dBu input level. To get the full output level from the AOW312B an input level of +10 dBu is needed at this setting.

Autostart and remote control

The RAM4 amplifier unit is equipped with an “Autostart” function, which automatically turns the amplifier to “standby” mode if an input signal has not been detected for approximately thirty minutes, and back to “on” mode when the signal returns. The function can be deactivated by turning the “AUTOSTART” dip switch on the back panel of the amplifier to “OFF”.

The amplifier mode can also be switched by a remote control unit connected to the respective inputs on the amplifier back panel. Two pairs of connectors are provided, 1 and 2 for a 12 V DC type remote control, and 3 and 4 for

an external switch or relay type control. Do not connect two remote controls to the loudspeaker at the same time. Activate the function by turning the "REMOTE CONTROL" dip switch to "ON". Note that the remote control function overrides the “AUTOSTART” dip switch function.

Setting the tone controls

The acoustic response of the system should be adjusted to match the acoustic environ- ment. The adjustment is done by setting the five tone control switch groups ‘bass tilt’, ‘bass roll-off’, ‘bass level’, ‘mid level’ and ‘treble level’ on the amplifier front panel. The manufactur- er’s default settings for these controls are ‘All Off’ to give a flat anechoic response. Figure 8 shows the effect of the controls on the anechoic response. Always start adjustment by setting all switches to the ‘OFF’ position. Then set only one switch per group to the ‘ON’ position to select the response curve required. If more than one switch is set to ‘ON’ (within one switch group) the attenuation value is no longer accurate.

Maintenance

The air filter on the left side of the RAM4 amplifier must be cleaned every six months. Remove the decorative front plate and pull the filter out. Check the filter and replace it with a new one if any damage or brittleness can be found. If the filter is in a good condi- tion, carefully clean it with compressed air.

No other serviceable parts are to be found within the loudspeaker enclosure or the amplifier unit. Any maintenance or repair should only be undertaken by qualified service personnel.

Safety considerations

Although the AOW312B loudspeaker and RAM4 amplifier have been designed in accordance with international safety stand- ards, to ensure safe operation and to maintain safe operating conditions, the following warnings and cautions must be observed:

1.Servicing and adjustment must only be performed by qualified service personnel. The amplifier must not be opened.

2.Do not use the amplifier with an unearthed mains cable or unearthed mains connection as this may lead to personal injury.