QSC Audio SC-433 User Manual
Sc-433, Cinema loudspeaker system
Developed specifically for the unique requirements
of professional motion picture playback, the SC-433
extends QSC’s commitment to the cinema market. As
a member of the DCS Digital Cinema Speaker Series,
the SC-433 is a 3-way, selectable bi or tri-amplified
screen channel loudspeaker system comprised of two
main units—the MH-1075 high-frequency system and
the LF-4315 low-frequency system.
The MH-1075 mid-high system features a high
output, horn loaded 10" midrange cone driver and a
3" (75mm) titanium diaphragm compression driver
mounted to an adjustable pan and tilt bracket. The
MH-1075 includes a driver protection network and
a passive crossover for bi-amp operation. Power
limiter circuitry protects the high-frequency driver
from overpowering. The MH-1075 provides extended
frequency coverage for the critical midrange band. A
high power 10" cone driver allows operation as low
as 250 Hz and the advanced phase plug coupling
permits a crossover point of up to 1800 Hz to the
high-frequency horn. This ensures that most of the
dialog range is reproduced by a single element, for
unmatched intelligibility.
The LF-4315 triple 15" (381mm) low-frequency
enclosure is designed specifically to address the
extended low-frequency response required for cinema
applications. The LF-4315 covers the frequency range
from 35 Hz to 250 Hz. Close Coupled Woofers
(CCW), with their tight spacing between woofers,
improves coupling and keeps coverage angles wide
over a greater frequency range than more widely
spaced designs.
The SC-433 is designed for ease of installation.
The MH-1075 components come pre-assembled to
reduce field assembly time. Three bolts are all that
are required to secure the MH-1075 to the top of the
LF-4315 enclosure.
SC-433
Cinema Loudspeaker System
Specifications
SC-433
Nominal Coverage
90° horizontal x +20 to -30° vertical
Frequency Range
32 Hz – 16 kHz (-6 dB)
Crossover Frequency
250 and 1700 Hz, 24 dB per octave
LF-4315
MH-1075
Impedance
5.5Ω
8Ω
Sensitivity 1 watt /1 meter,
99.5 dB
Bi-amp
Tri-amp
half space
105 dB
MF 105 dB HF 107.5 dB
Maximum Input Power
1
8 hours of 6 db crest factor
1200 W RMS
250 W RMS
2
275 W RMS 80 W RMS
IEC 268 noise spectrum
2 hours of 6 db crest factor
1500 W RMS
350 W RMS
pink noise, 50 Hz – 20 kHz,
AES method
Recommended Amplifier Power 2400 W RMS maximum
800 W RMS maximum
Recommended Processing
Subsonic filter below 30 Hz,
4th order LR crossover at 200 and 1700
> 18 dB per octave
Hz via QSC DCM or QSControl.net™
Connectors
Barrier strip screw terminals
Barrier strip screw terminals
accept up to #10 AWG
accept up to #10 AWG stranded wire
stranded wire
Transducers
Three 15" (381mm) high efficiency, 10" high efficiency mid range,
extended bass woofer featuring 1.5" (38mm) exit, 3" titanium
4" copper voice coils
diaphragm compression driver
Enclosure
Quasi B4 alignment, ported
Tilt/Pan Bracket
enclosure with fully flared ports,
±10° vertical tilt
symmetrical port design, tuned to ±10° horizontal pan
36 Hz, constructed of MDF and
heavily braced. Features vandal
resistant woofer mounting bolts
Dimensions (HWD)
53" x 30" x 20.3"
39" x 30" x 20"
(1344 mm x 762 mm x 516 mm) (990 mm x 762 mm x 508 mm)
Weight – Net
260 lb (118 kg)
85 lb (39 kg)
System Weight
345 lb (157 kg)
Baffle Cut-Out
93" x 32"
1) Maximum input power tested in accordance with IEC 268-5 recommendations, 50 Hz – 20 kHz band limiting, 6 dB signal crest factor.
2) Maximum input power tested in accordance with IEC 268-5 recommendations, 200 Hz – 2 kHz band limiting, 6 dB signal crest factor.
passive
mid-high
Features
• 3-way selectable, bi or tri- amplified screen channel system
• MH-1075 provides 90° horizontal by +20° to -30° vertical coverage
• LF-4315 is constructed of MDF and features single woofer chambers
• Low-distortion waveguides provide highly articulate dialogue
• Shallow depth (20") facilitates installation
• THX™ approved for professional cinema applications