Developed specifically for the unique requirements
of professional motion picture playback, the SC-422
extends QSC’s commitment to the cinema market. As
a member of the DCS Digital Cinema Speaker Series,
the SC-422 is a two-way, bi-amplified screen channel
loudspeaker system comprised of two main units—the
HF-75 high-frequency system and the LF-4215 low-
frequency system.
The HF-75 high-frequency system features a large
format, 3
"
(75mm) titanium diaphragm compression
driver mounted on a custom designed high-frequency
cinema horn with an adjustable pan and tilt bracket.
The HF-75 includes a driver protection and equalization
network. DC blocking capacitors protect against DC or
low-frequency signals that would likely destroy an
unprotected driver. Power limiter circuitry protects the
driver from overpowering and a response correction
filter smoothes the frequency response of the horn/
driver combination. The driver and equalization
network provides for more reliable operation, ensuring
the show will go on.
The LF-4215 dual 15
"
(381mm) low-frequency
enclosure is designed specifically to address the
extended low-frequency response required for cinema
applications. The LF-4215 covers the frequency range
from 35 Hz to 1000 Hz, depending upon the
high-frequency system requirements. 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-422 is designed for ease of installation.
The HF-75 components come pre-assembled to
reduce field assembly time. Three bolts are all that
are required to secure the HF-75 to the top of the
LF-4215 enclosure.
SC-422
Cinema Loudspeaker System
Specifications
SC-422
Nominal Coverage
90° horizontal x +20 to -30° vertical
Frequency Range
38 Hz - 16 kHz (-6 dB)
Crossover Frequency
700 Hz, 24 dB per octave
LF-4215
HF-75
Impedance
4
Ω
8
Ω
Sensitivity 1 watt /1 meter,
99.5 dB
107.5 dB
half space
Maximum Input Power
1
8 hours of 6 db crest factor
800 W RMS
60 W RMS
IEC 268 noise spectrum
2 hours of 6 db crest factor
1000 W RMS
80 W RMS
pink noise, 50 Hz - 20 kHz,
AES method
Recommended Amplifier Power 1600 W RMS maximum
100 W RMS maximum
Recommended Processing
Subsonic filter below 30 Hz,
4th order LR crossover at 1000 Hz
> 18 dB per octave
Connectors
Barrier strip screw terminals
Barrier strip screw terminals
accept up to #10 AWG
accept up to #10 AWG
stranded wire
stranded wire
Transducers
Two 15" (381mm) high efficiency,
1.5" (38mm) exit, 3" titanium
extended bass woofer featuring
diaphragm compression driver
4" copper voice coils
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)
36" x 30" x 20.3"
16" x 30" x 20"
(910 mm x 762 mm x 516 mm)
(406 mm x 762 mm x 508 mm)
Weight - Net
172 lbs (78 kg)
40 lbs (18.4 kg)
System Weight
212 lbs (96.4 kg)
Baffle Cut-Out
53" 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.
Features
• Two-way, bi-amplified screen channel system
• HF-75 provides 90° horizontal by +20° to -30° vertical coverage
• LF-4215 is constructed of MDF and features single woofer chambers
• Low-distortion waveguide provides highly articulate dialogue
• Shallow depth (20") facilitates installation
