The USW-1 operates as a system with
the B-2EX Control Electronics Unit (one
per channel). Optimized for use with Meyer
Sound subwoofers, and pre-aligned at the
factory, the B-2EX contains frequency
response and phase response alignment
circuitry, and Meyer Sound’s exclusive
SpeakerSense
driver protection circuitry,
incorporating RMS signal limiting and
switchable excursion limiting.
A single-channel device operating at
line level, the B-2EX is intended to be the
final component in the signal chain before
the power amplifier. It is connected in
parallel with the input to the system being
supplemented by the USW-1, and incorpo-
rates a summing input for deriving a mono
subwoofer signal from a stereo program.
The factory-calibrated SpeakerSense
circuitry protects the USW-1 loudspeaker
components from damage due to over-
heating under high power conditions. This
unique circuit continuously monitors the
power applied to the USW-1 drivers, and
limits the B-2EX output when the safe
operating limits of the drivers are ex-
ceeded. Until the onset of overload, the
SpeakerSense circuitry has no effect on the
B-2EX output signal.
Included in the SpeakerSense circuit
is a Safe switch, which moves the limit
point down by 6 dB and engages the
excursion limiter. This has the effect of
increasing the safety margin of the system,
and is intended to be used when extended
periods of overload are anticipated. In
addition to these features, the B-2EX
incorporates a Crossover switch which
engages/disengages the lowpass rolloff of
the subwoofer output. This feature may be
used whenever it is desireable to operate the
USW-1 full-range as, for example, in
instrument amplification
The setup controls are located behind
a cover plate on the B-2EX front panel,
providing a means for securing the system
installer’s presets.

The B-2EX Control

Electronic Unit

UltraSeries™ B-2EX
Power
Sense Limit
20
10 843
2
1
0
Attn dB
5
6
Excursion
Safe
Out
Crossover
Safe