OPERATING INSTRUCTIONS
SUBWOOFER SYSTEM
FB-120B
FB-120W
Thank you for purchasing TOA's Subwoofer System.
Please carefully follow the instructions in this manual to ensure long, trouble-free use of your equipment.
1. SAFETY PRECAUTIONS
• Before installation or use, be sure to carefully read all the instructions in this section for correct and safe operation.
• Be sure to follow all the precautionary instructions in this section, which contain important warnings and/or cautions
regarding safety.
• After reading, keep this manual handy for future reference.
Indicates a potentially hazardous situation which, if mishandled, could result
in death or serious personal injury.
WARNING
Indicates a potentially hazardous situation which, if mishandled, could result
CAUTION
in moderate or minor personal injury, and/or property damage.
• Use nuts and bolts that are appropriate for the ceiling's
structure and composition. Failure to do so may cause
the speaker to fall, resulting in material damage and
possible personal injury.
WARNING
• Refer all installation work to the dealer from whom the
• Tighten each nut and bolt securely. Ensure that the
bracket has no loose joints after installation to prevent
accidents that could result in personal injury.
speaker was purchased. Installation for flying requires
extensive technical knowledge and experience. The
speaker may fall off if incorrectly installed, resulting in
possible personal injury.
• Do not mount the unit in locations exposed to constant
vibration. The mounting bracket can be damaged by
excessive vibration, potentially causing the unit to fall,
which could result in personal injury.
• Flying Precautions
Be sure to follow the instructions below. Otherwise, the
suspension wires or belts may be off or snap and the
speaker may fall off, causing personal injury.
• Check to confirm that the suspension wires and belts are
strong enough to withstand the speaker load.
CAUTION
• Avoid touching the unit's sharp metal edge to prevent
• The connectors of the suspension wires and belts must
be securely linked with those of the speaker.
injury.
• All parts and components (such as enclosures, metal
pieces, and screws) must be free from any deformation,
crack, and corrosion.
• To avoid electric shocks, be sure to switch off the
amplifier's power when connecting speakers.
• Do not place heavy objects on the unit as this may cause
it to fall or break which may result in personal injury
and/or property damage. In addition, the object itself may
fall off and cause injury and/or damage.
•
Be sure to use screws supplied with the optional flying
hardware when installing the speaker using such hardware.
• Install the unit only in a location that can structurally
support the weight of the unit and the mounting bracket.
Doing otherwise may result in the unit falling down and
causing personal injury and/or property damage.
• Do not operate the unit for an extended period of time
with the sound distorting. This is an indication of a
malfunction, which in turn can cause heat to generate
and result in a fire.
• Since the unit is designed for in-door use, do not install it
outdoors. If installed outdoors, the aging of parts causes
the unit to fall off, resulting in personal injury.
• Do not stand or sit on, nor hang down from the unit as
this may cause it to fall down or drop, resulting in
personal injury and/or property damage.
• Owing to the unit's size and weight, be sure that at least
two persons are available to install the unit. Failure to do
so could result in personal injury.
• Have the unit checked periodically by the shop from
where it was purchased. Failure to do so may result in
corrosion or damage to the unit or its mounting bracket
that could cause the unit to fall, possibly causing
personal injury.
• Do not use other methods than specified to install the
unit. Extreme force is applied to the unit and the unit
could fall off, possibly resulting in personal injuries.
First speaker
Second speaker
• Two speaker systems can be operated in parallel by connecting them in a
cascade configuration as shown at right.
Note
Be sure to connect the speaker system to the power amplifier's output
terminal of 4 Ω or less.
Connecting it to an output terminal of over 4 Ω may cause amplifier failure.
6. INSTALLATION
6.1. Installation Location and Acoustic Energy
Acoustic energy emitted from the speaker differs depending on installation locations.
The figures below show that the acoustic energy increases in other installation locations, referenced to the free sound field
(ceiling suspension).
2 π space: +6 dB
(Semi-free sound field)
4 π space: +0 dB
(Free sound field)
π/2 space: +18 dB
(1/8 free sound field)
π space: +12 dB
(1/4 free sound field)
6.2. Suspended Installation
Be sure to select wire, chain, and/or anchor shackles with a safety factor
appropriate to the weight of the speaker system. Incorrect selection of these
suspension components may cause the speaker system to fall, potentially
resulting in damage and/or personal injury.
WARNING
Remove the 4 screws on both sides of the subwoofer system, screw 30 – 50 mm (1 3/16" – 1 31/32") M8 eyebolts into the
exposed holes, and use these to suspend the subwoofer using wire or chain.
Note
Eyebolts, nuts, and washers are not supplied and should be acquired separately.
Remove the 4 preinstalled
screws on both sides.
M8 eyebolt
(30 – 50 mm or 1 3/16" – 1 31/32" long)
Use the optional HY-PF1B or HY-PF1W Speaker Rigging Frame to suspend the FB-120 subwoofer together in the same
location with TOA HX-5 series speakers.
For suspension, refer to the instruction manual attached to the HY-PF1B or HY-PF1W.
7. COMBINING THE FB-120 WITH FULL-RANGE SPEAKERS
7.1. Crossover Settings
The subwoofer system already possesses the characteristic of suppressing sound in the mid- to high-frequency range, but
a low-pass filter can also be added to eliminate unwanted mid- and high-frequency components even further for even
greater efficiency. When using a digital signal processor as a low-pass filter, the filter settings shown below are
recommended.
Filter
(12 dB/oct)
LPF BW (24 dB/oct)
Frequency
40 Hz
Q
HPF
2.053
100 Hz
7.2. Level Balance & Polarity
When using the FB-120 series in conjunction with full-range speakers (such as those in TOA's HX-5 series), adjust the
level balance and polarity for each speaker independently depending on the installation site.
7.2.1. Level balance adjustment
Increase or decrease the level of the subwoofer (or full range speaker) as appropriate to the number of units and
installation conditions.
7.2.2. Polarity adjustment
• If the subwoofer and full-range speakers are in phase in their crossover band, then acoustic energy is added; however,
acoustic energy is subtracted if the two are in reversed phase. Since the phase characteristics of both the subwoofer
and full-range speaker change continuously depending on the frequency, it may not be ideal to follow the subwoofer's
polarity instructions when connecting it.
• Compare the degree to which acoustic energy increases by switching the polarity of the connection at the subwoofer
(from positive to negative and from negative to positive). Choose the way of connection that results in the greatest
increase in acoustic energy. To match the polarity correctly, make actual measurements of acoustic energy using a real
time spectrum analyzer.
8. SPECIFICATIONS
Model No.
FB-120B
FB-120W
Power Handling Capacity
Impedance
Continuous pink noise: 200 W, Continuous program: 600 W
8 Ω
Sensitivity
90 dB (1 W, 1 m) at installation in free sound field
96 dB (1 W, 1 m) at installation in 1/2 free sound field
Frequency Response
Speaker Component
Input Terminal
40 to 1,200 Hz (–10 dB)
30 cm (12") cone-type
Speakon NL4MP x 2 and M4 screw terminals,
distance between barriers: 11 mm
Finish
Enclosure:
Punched net: Steel plate, black, paint
408 (w) x 408 (h) x 450 (d) mm
Wood
Enclosure:
Punched net: Steel plate, white, paint
Wood
Dimensions
Weight
16 1/16 (w) x 16 1/16 (h) x 17 23/32 (d) inches
15 kg
Note: The design and specifications are subject to change without notice for improvement.
• Optional products
Speaker rigging frame: HY-PF1B (black), HY-PF1W (white)
Printed in Indonesia
533-06-126-60
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