Specifications - Toa FB-120B Operating Instructions

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
HPF (12 dB/oct)
LPF BW (24 dB/oct)
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.
Power Handling Capacity
Impedance
Sensitivity
Frequency Response
Speaker Component
Input Terminal
Finish
Dimensions
Weight
Note: The design and specifications are subject to change without notice for improvement.
• Optional products
Speaker rigging frame: HY-PF1B (black), HY-PF1W (white)
Frequency Q
40 Hz 2.053
100 Hz –
FB-120B
Continuous pink noise: 200 W, Continuous program: 600 W
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
Speakon NL4MP x 2 and M4 screw terminals,
distance between barriers: 11 mm
Enclosure: Wood
Punched net: Steel plate, black, paint
408 (w) x 408 (h) x 450 (d) mm
16
1/16
8 Ω
40 to 1,200 Hz (–10 dB)
30 cm (12") cone-type
Enclosure:
Punched net: Steel plate, white, paint
(w) x 16 (h) x 17
1/16 23/32
15 kg
FB-120W
Wood
(d) inches
Printed in Indonesia
533-06-126-60