or 8030A’s should be attenuated by turning
the volume control knob on the front panel of
the loudspeakers. On the 8020A/B the knob
should be turned anticlockwise to approxi-
mately 12 o’clock position and on the 8030A
to 2 o’clock position respectively.
Setting the subwoofer level
The rotary subwoofer level control is located
on the connector panel of the subwoofer.
The factory default input sensitivity is -6 dBu
(9 o’clock). You can use this adjustment to
match the subwoofer’s playback level with
the main loudspeakers.
Setting the Bass
Roll-Off switches
The acoustic response of the subwoofer
may have to be matched to the characteris-
tics of the room and the positioning in which
it will be used (see Table 1). To adjust the
subwoofer to match these characteristics
use the ‘’BASS ROLL-OFF’ control switches
located on the connector panel. When all
Roll-Off switches are ‘OFF’, a flat anechoic
response is obtained.
Setting the phase control
The effect of incorrect phase alignment
between the main loudspeakers and the
subwoofer is a drop in the frequency
response of the whole system at the main
loudspeaker / subwoofer crossover fre-
quency. The phase difference between the
main loudspeakers and subwoofer at the
listening position is dependent upon the dis-
tance from the listener to the subwoofer in
relation to the main loudspeakers. To avoid
phase differences between the left and right
main loudspeakers and the subwoofer, the
subwoofer should be placed close to the
center of the front loudspeaker array.
Two phase matching switches in the
crossover allow compensation for incorrect
phase alignment. Four settings are provided
between 0° and -270°.
Coarse phase
correction method
Connect an audio frequency signal generator
to a signal input on the subwoofer which has
a main loudspeaker connected to the corre-
sponding “OUT” connector. Set the generator
to 85 Hz. If a signal generator is not available,
it is possible to use an audio test recording
which has a test frequency in the range 70
Hz to 100 Hz. Suitable test signals can be
downloaded at www.genelec.com.
Toggle the -180°
phase switch ‘ON’
and ‘OFF’ and set it
to the position which
gives the lowest
sound level at the
listening position.
Next toggle the
-90°phase switch
‘ON’ and ‘OFF’,
and again set it
to the position
which gives the
lowest sound level.
Finally, set the
-180°phase switch
to the opposite set-
ting.
Using the 5051A subwoofer
When the subwoofer is powered up or after
being disconnected from the mains supply,
the green power indicator LED blinks and
the subwoofer stays muted for approximately
seven seconds. This is normal and after this
the LED lights up and playback begins.
The delay allows matching the remote
control to a specific subwoofer unit (see
chapter “Matching the remote control to the
subwoofer” below). This is only necessary
when there are several 5051A subwoofers
within the range of the remote control (in
adjacent rooms, for instance) and the user
wishes to avoid the situation that more than
one subwoofer reacts to the commands
given by the remote control.
The playback volume can be adjusted with
the + and - buttons on the remote control
(see Figure 3). The LED on the subwoofer
connector panel blinks while the adjustment
is being done and stops blinking when the
minimum or maximum level of the adjustment
range is reached.
The 5051A can be muted by a short push
on the POWER/STANDBY button. A new
short push on the POWER/STANDBY button
or the + button resumes playback. The power
indicator LED blinks approximately once per
second to indicate that the subwoofer is in
“mute” mode. Pushing the - button while the
subwoofer is muted reduces the volume set-
ting.
Switch the 5051A to stand-by mode by
pushing and holding the POWER/STANDBY
button down until the power indicator LED
switches off. Respectively, the subwoofer
powers up again with a push on the POWER/
STANDBY button.
The 5051A is equipped with an automatic
signal sensing function that switches the
subwoofer to stand-by mode if no signal is
present in the audio input for approximately
one hour. The subwoofer resumes playback
automatically when it detects an audio signal
being fed into any of the input connectors.
Alternatively, the subwoofer can be activated
by pushing any button on the remote control.
Automatic protection function
The 5051A has an integrated protection func-
tion that automatically reduces the playback
volume to a safe level if the subwoofer is
overloaded. This function overrides com-
mands given with the remote control. The
power indicator LED turns to orange colour
to indicate clipping and then to red to indicate
VOLUME
CONTROL
BUTTONS
POWER /
STANDBY
BUTTON
Subwoofer
placement
Bass Roll-Off
Near a wall
-4 dB (sw 4 “ON”)
In a corner
-6 dB (sw 3 “ON”)
Table 1. Suggested Bass Roll-Off settings in
typical situations
ON
OFF
7
6
5
ON
OFF
7
6
5
ON
OFF
7
6
5
Figure 3. 5051A remote control