Bosch LBC3951-11-US Specsheet

Communications Systems | LBC 3951/11 Ceiling Loudspeaker

LBC 3951/11 Ceiling Loudspeaker

www.boschsecurity.com

u Compact yet powerful

u Very wide opening angle

u Modern unobtrusive styling

The LBC 3951/11 is a compact, 6 W loudspeaker with
a perforated metal grille. It has excellent audio
performance and is easy to install with its integral
mounting clips. The loudspeaker is IPx4 water
protected from the front so it can be installed in
humid environments.

Functions

The LBC 3951/11 has a perforated metal grille with a
plastic surround, finished in an attractive off-white
RAL color. The unobtrusive styling of this loudspeaker
complements today’s interior lighting.
The loudspeaker feature a very wide opening angle,
which means fewer units are required to cover a given
area. The wide frequency range means better speech
and music reproduction. The unit is supplied with a
100 V matching transformer with taps on the primary
winding for full-power, half-power, quarter-power and
eighth-power radiation.
The loudspeaker (with special treated paper cone), is
IPx4 water protected from the front and can be
applied in humidity environments for example
bathrooms, saunas, atriums and swimming pool areas.

u Installation friendly

u Splash - waterproof

Certifications and approvals

All plastic parts are manufactured from self­extinguishing high-impact ABS material (according to
UL 94V0).
All Bosch loudspeakers are designed to withstand
operating at their rated power for 100 hours in
accordance with IEC 268-5 Power Handling Capacity
(PHC) standards. Bosch has also developed the
Simulated Acoustical Feedback Exposure (SAFE) test
to demonstrate that they can withstand two times
their rated power for short durations. This ensures
extra reliability under extreme conditions, leading to
higher customer satisfaction, longer operating life, and
much less chance of failure or performance
deterioration.

Safety acc. to EN 60065

Water protected acc. to EN 60529, IPx4

Region Certification

Europe CE

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2 | LBC 3951/11 Ceiling Loudspeaker

Installation/configuration notes

Installation is easy with integral clips that securely
hold the ceiling loudspeaker in its cut-out. Ceilings
from 9 to 25 mm thick can be accommodated. A
template is also provided for accurately marking the
cutout in ceiling panels. Wiring is via a connection
block with push-type terminals, making installation
possible without using any special tools. The terminal
blocks have provision for loop-through wiring. The
transformer is delivered wired for 6 W rated output
power, but can easily be changed for other
connections using the color-coded wires and terminal
block.

Frequency response

01Clamp

02Matching transformer

03Terminal block

Dimensions in mm (inch)

Circuit diagram

Polar diagram

125Hz250Hz500Hz1

kHz2kHz4kHz8kH

z

SPL 1.1 87 87 85 88 89 89 86

SPL max. 95 95 93 96 97 97 94

Q-factor 4 5.6 2.2 3.2 4.6 10.719

Efficiency0.16 0.110.180.250.220.090.

03

H. angle 180 180 180 170 160 80 60

V. angle 180 180 180 170 160 80 60

Acoustical performance specified per octave

Technical specifications

Electrical*

Maximum power 9 W

Rated power 6 / 3 / 1.5 / 0.75 W

Sound pressure level
at 6 W / 1 W (1 kHz, 1 m)

96 dB / 88 dB (SPL)