QSC Audio HF-63X1 User Manual
Sc-312x, Cinema loudspeaker system
 
Developed specifically for the unique requirements 
of professional motion picture playback, the SC-312X 
extends QSC’s commitment to the cinema market. As 
a member of the DCS Digital Cinema Speaker Series, 
the SC-312X is a passive, 2-way, screen channel 
loudspeaker system comprised of two main units—the 
HF-63X1 high frequency system and the LF-3115 low-
frequency system. 
The HF-63X1 high-frequency system features a 2.5" 
(63mm) titanium diaphragm compression driver 
mounted on a custom designed high frequency 
cinema horn with an adjustable pan and tilt bracket. 
The HF-63X1 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-3115 15" (381mm) low-frequency enclosure 
is designed specifically to address the extended low-
frequency response required for cinema applications. 
The LF-3115 covers the frequency range from 
35 Hz to 1000 Hz, depending upon the high-
frequency system requirements.
The SC-312X is designed for ease of installation. 
The HF-63X1 components come pre-assembled to 
reduce field assembly time. Three bolts are all that 
are required to secure the HF-63X1 to the top of the 
LF-3115 enclosure.
SC-312X
Cinema Loudspeaker System
Specifications
SC-312X
Nominal Coverage
90° horizontal x +15 to -35° vertical
Frequency Range
33 Hz – 16 kHz (-6 dB)
Impedance
8Ω
Sensitivity 1 watt /1 meter,
95 dB
half space
Maximum Input Power
1
2 hours of 6 db crest factor
150 W RMS
pinknoise, 50 Hz – 20 kHz,
AES method
Recommended Amplifier Power 300 W RMS maximum
Recommended Processing
Subsonic filter below 30 Hz, > 18 dB per octave
LF-3115
HF-63X1
Connectors
Barrier strip screw terminals
Barrier strip screw terminals
accept up to #10 AWG
accept up to #10 AWG
stranded wire
stranded wire
Transducers
One 15" (381mm) high efficiency,
1.5" (38mm) exit, 2.5" titanium
extended bass woofer featuring a
diaphragm compression driver
3" copper voice coil
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)
18.5" x 30" x 20.3"
16" x 30" x 20"
(470 mm x 762 mm x 516 mm)
(406 mm x 762 mm x 508 mm)
Weight – Net
83 lb (38 kg)
40 lb (18.4 kg)
System Weight
123 lb (56.4 kg)
Baffle Cut-Out
35.5" 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
• Passive, 2-way, screen channel system
• SC-312X provides 90° horizontal by +15° to -35° vertical coverage
• Low distortion waveguide provides highly articulate dialogue
• Shallow depth (20") facilitates installation