Operating Manual
Figure 2. XLR to RCA connector for
unbalanced operation.
Figure 3. Recommended distances to
the front wall
Figure 1. 7050B's amplifier panel, connectors and controls.
.1 output channel of a 5.1-channel discrete
surround sound source.
placing them at least 110 cm / 43" away from
any objects to ensure proper functioning of
the reflex port.
the front wall (see Figure 2).
Once all connections have been made, the
subwoofer and main loudspeakers are ready
to be powered up.
If the frequency balance does not seem
right, try moving the subwoofer slightly to
the left or right so that different room modes
are excited at different levels. Positioning
the subwoofer close to a corner will boost
the bass level at lower frequencies and may
cause asymmetrical spatial imaging.
Flush mounting the subwoofer
If the subwoofer is flush mounted into a wall
or a cabinet, it is important to ensure ampli-
fier cooling and unrestricted airflow from the
reflex port. This can be done by making the
recess 7,5 centimeters (3") wider than the
subwoofer. Place the subwoofer into the right
end of the recess with the driver side facing
the room. This leaves sufficient 7,5 centime-
ters (3") of free space on the reflex port side.
The height and depth of the recess should
not be any bigger than is needed to fit the
subwoofer flush with the wall surface.
Positioning in the room
The placement of the subwoofer in the room
affects the overall frequency response and
sound level of the system dramatically, as at
low frequencies the effects of the room are
strong. Even a slight change in the subwoof-
er's location can make a marked difference in
the frequency balance and often patient and
methodical experimentation and testing is
needed to find the optimum placement. The
placement will affect the phase difference
between the main loudspeakers and the sub-
woofer and the bass roll-off rate.
Although the 7050B is magnetically
shielded, it may cause colour distortion if
placed near to very sensitive video loudspeak-
ers or computer displays. Move the subwoofer
further away or try turning the driver side of
the subwoofer away from the screen
Minimum clearances to walls
or other objects
Do not cover the driver side of the subwoofer
or place the subwoofer so that there is less
than 10 cm (4") of free space in front of the
grille.
Sensitivity adjustment
The subwoofer requires input sensitivity
alignment to the source to obtain a correctly
balanced system. The input sensitivity con-
trol is located on the connector panel of the
subwoofer. An input voltage of -6 dBu with a
-6 dBu input sensitivity setting will produce
100 dB SPL @ 1 m in free field.
First place the subwoofer slightly offset
from the center of the front wall. The rec-
ommended distance to the wall is less than
60 cm / 24" measured from the subwoofer's
driver. This position gives increased acoustic
loading (and SPL) due to the proximity of the
front wall and floor. Cancellations from the
front wall and floor are also avoided. Front
wall cancellation for the 85 Hz high pass fil-
tered main speakers can be eliminated by
Make sure that the space underneath the
subwoofer is clear from obstructions. Thick
carpets may block the ventilation clearance
needed for cooling the electronics.
Setting the phase control
Incorrect phase alignment between the
The reflex port side (opposite of the con-
nector panel side) should always have a
clearance of at least 7,5 centimeters (3") to
main loudspeakers and subwoofer causes
Subwoofer placement
Bass Roll-Off
setting
Near to a wall
In a corner
-2 dB
-6 dB
-2 dB
Flush mounted
Table 1. Suggested Bass Roll-Off settings
Phase Difference: 0°
Phase Difference: 90°
85 Hz
85 Hz
Phase Difference: 180°
Phase Difference: 270°
85 Hz
85 Hz
Figure 5. Flush mounting the subwoofer.
Note the clearance needed on the reflex
port side.
Figure 4. The effect of phase difference between the subwoofer and the main loudspeakers
a drop in the frequency response of the
whole system at the crossover frequency.
The graphs above (Fig. 4) show the effect of
phase difference to the frequency response.
The phase difference between the main
loudspeakers and subwoofer at the listen-
ing position is dependent upon the position
of the subwoofer, so the phase adjustment
should be done only after the preferred posi-
tion is found. Acoustic measuring equipment
is required for accurate system alignment. If
this equipment is not available, the following
coarse phase matching can be applied.
to the position which gives the lowest sound
level at the listening position.
Change the -180° switch to the opposite
setting. The phase should now be set cor-
rectly and the frequency analyser should
show a smooth response around 85 Hz.
Next toggle the -90° phase
switch (DIP 4) "ON" and
"OFF", and again set it to
the position which gives
the lowest sound level.
Using the LFE Bandwidth and
LFE +10 dB functions
The “LFE BANDWIDTH” switch allows you to
select the upper cutoff frequency of the LFE
channel between 85 and 120 Hz. Limiting the
LFE bandwidth to 85 Hz can be used to simu-
late the effect of some consumer decoders
that do not replay information above 80 Hz on
the LFE channel when the bass management
is used. Checking the multichannel mix with
this setting on lets you know how it translates
in systems with this limitation.
Finally, set the -180° phase
switch (DIP 5) to the oppo-
site setting and deactivate
the test signal.
Coarse phase adjustment
method
Phase correction method with
test equipment
Connect an audio frequency signal generator
to the “FRONT CENTER” input of the 7050B
and set it to feed a 85 Hz signal to the system.
Alternatively, you can use a 85 Hz signal fom
a suitable audio test recording. Make sure
you connect (even temporarily) a main loud-
speaker to the "FRONT CENTER" output, so
that the test signal is properly reproduced by
both subwoofer and main loudspeaker.
The following procedure matches the phase
between the subwoofer and the main loud-
speakers using a frequency analyser and a
pink noise generator. Connect a high grade
measuring microphone to the analyser and
feed pink noise into the "CENTER IN" input of
the subwoofer. Position the microphone at the
listening position and adjust the input sensi-
tivity of the subwoofer until frequencies below
and above 85 Hz are reproduced at equal
level. Then adjust the phase control switches
for the maximum dip of at least -6 dB at the
crossover frequency (85 Hz).
The 120 Hz LFE bandwidth setting com-
plies with the replay systems of movie theat-
ers and cinemas. 35 mm movie soundtracks
use the LFE channel to reproduce a band-
width of 20 - 120 Hz through dedicated
subwoofers. In this case the LFE and main
channel bandwidths overlap between 85 and
120 Hz, which may create unwanted acousti-
cal summing if the same signal is present in
both channels. To avoid this, the LFE content
should be kept completely different (de-cor-
related) from the low frequency content of
Toggle the -180° phase
switch (DIP 5 from left)
"ON" and "OFF", and set it
the main channels when mixing music and
sound effects for film release.
Do not obstruct airflow around the
subwoofer.
In Dolby Digital and DTS encoding formats
the LFE channel has to be monitored with
+10 dB gain in relation to the main channels.
The object is to increase the recording head-
room of the LFE channel. Consumer and the-
atrical decoders automatically add +10 dB of
LFE gain to restore the level balance.
•
Note that the amplifier is not completely
disconnected from the AC mains service
unless the mains power cord is removed
from the amplifier or the mains outlet.
Warning!
This subwoofer is capable of delivering sound
pressure levels in excess of 85 dB, which
may cause permanent hearing damage.
The "LFE +10 dB" function on the 7050B
subwoofer is designed to add the +10 dB
gain to the LFE channel in the production
stage, if it is not already done in the output
matrix of the mixing console. The function is
activated by switching the "LFE +10 dB" dip
switch on the subwoofer to "ON". The "LFE
+10 dB" function should not be used in fol-
lowing cases:
Maintenance
No user serviceable parts are inside the
subwoofer. Any maintenance of the unit must
only be performed by qualified service per-
sonnel.
Figure 6. The free field frequency
response of the 7050B subwoofer at
different Bass Roll-Off settings
Guarantee
•
If the +10 dB LFE gain is already
implemented by another device.
This product is supplied with a ONE year
guarantee against manufacturing faults or
defects that might alter the performance of
the unit. Refer to supplier for full sales and
guarantee terms.
•
When producing an audio format that
does not require the use of +10 dB
gain on the LFE channel, such as
DVD-Audio (MLP), SACD (DSD) etc.
When monitoring a decoded Dolby
Digital or DTS soundtrack. The decoder
will automatically provide +10 dB
LFE gain.
•
EC Declaration of Conformity
This is to certify that Genelec 7050B Active
Subwooferconformtothefollowingstandards:
Safety considerations
Safety:
Genelec 7050B subwoofer has been
designed in accordance with international
safety standards. However, to ensure safe
operation and maintain the unit in safe oper-
ating condition, the following warnings and
cautions must be observed:
EN 60065 / IEC 60065:1998 6th Edition
EMC:
EN 55020 : 2002 + A1 : 2003
EN 55020: (1994), A11: (1996), A12: (1999),
A13: (1999), A14: (1999)
EN 61000-3-2 (2000)
•
•
•
•
•
Servicing and adjustment must only be
performed by qualified service
EN 61000-3-3 (1995)
personnel. The subwoofer cabinet or
electronics unit must not be opened.
Do not use this subwoofer with an
unearthed mains cable or an unearthed
mains connection as this may
The product herewith complies with the
requirements of The Low Voltage Directive
73/23/EEC, EMC Directive 89/336/EEC and
93/68/EEC
harmonic distortion analysis of the 7050B
in free field. In half space the SPL will be
6 dB higher.
compromise electrical safety.
Do not expose the subwoofer to water
or moisture. Do not place any objects
filled with liquid, such as vases on the
subwoofer or near it.
Signed:
Ilpo Martikainen
Position: Managing Director
Date:
3-May-2005
This subwoofer is capable of producing
sound pressure levels in excess of
85 dB, which may cause permanent
hearing damage.
Free flow of air around the subwoofer is
necessary to maintain sufficient cooling.
7050B Operating Manual
SYSTEM SPECIFICATIONS
AMPLIFIER SECTION
7050B
7050B
Free field frequency response (± 3 dB)
25 Hz...85 Hz
LFE 85/120 Hz
Amplifier short term output power
(Long term output power is limited by driver
unit protection circuitry)
70 W
Maximum short term sine wave SPL output
averaged from 30 to 85 Hz, measured in half
space at 1 meter
100 dB
Amplifier system THD at nominal output
Mains voltage
≤ 0.08 %
100, 120 or 230 V
Self generated noise level in half space at 1 m ≤ 15 dB
on axis (A-weighted)
Power consumption (average)
Idle
Full output
11 VA
120 VA
Harmonic distortion at 90 dB SPL
at 1 m on axis in half space 30… 85 Hz
2nd
3rd
≤ 4%
≤ 1 %
Driver, magnetically shielded
Weight
205 mm (8")
18 kg (39.6 lb)
Dimensions
Height
INPUT SECTION
410 mm (161/8”)
350 mm (133/4”)
319 mm (129/16”)
7050B
Width
Depth
Input connectors XLR female
pin 1
pin 2
pin 3
gnd
+
Input impedance
10 kohm balanced
Input level for 100 dB SPL output @ 1 m
Variable from +12 to -6
dBu
CROSSOVER SECTION
7050B
Subsonic filter (18 dB/octave) below
Input channels
25 Hz
5 main + LFE
85 Hz
OUTPUT SECTION
7050B
Low pass frequency for 5 main channels
LFE cutoff frequency
Input connectors XLR male
85 or 120 Hz selectable
≥ 50 dB
pin 1
pin 2
pin 3
gnd
+
Midband rejection >400 Hz
Bass Roll-Off control in 2 dB steps
Phase matching control in 90° steps
Input sensitivity control
0 to -6 dB @ 26 Hz
0 to -270°
Main loudspeaker Out gain
0 dB
Main loudspeaker Out connectors carry an unfiltered copy of the signal
arriving into their respective Input connectors.
+12 to -6 dBu
0 or +10 dB selectable
LFE input sensitivity control
Genelec Document D0061R001 Copyright Genelec Oy 5.2005. All data subject to change without prior notice
In Sweden please contact
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Email [email protected]
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