Q-SYS SC-424 Tri or Quad-Amp 4-Way 2x15-inch Cinema Loudspeaker System with LF-4215 and MHV-1090

Developed specifically for the unique requirements of professional motion picture playback, the SC-424 extends QSC’s commitment to the cinema market. As a member of the DCS Digital Cinema Speaker Series, the SC-424 is a 4-way, selectable tri or quad-amplified screen channel loudspeaker system comprised of two main units – the MHV-1090 mid-high-very high-frequency system and the LF-4215 low-frequency system.

The MHV-1090 mid-high-very high system features a high output, horn loaded 10” midrange cone driver and a coaxial neodymium high-frequency/very high-frequency compression driver. The MHV-1090 includes a driver protection network and a passive crossover for tri-amp operation. The protection circuitry prevents low-frequency signals from damaging the high-frequency and very high-frequency driver. 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 coaxial neodymium high-frequency/very high-frequency compression driver provides a dramatic improvement in dynamic response, clarity and transparency. The annular high-frequency diaphragm covers the frequency range between 1800 and 7000 Hz with a smooth, linear response. The large diaphragm excursion of +/-0.8 mm results in high output and increased power handling. The very high-frequency driver covers the frequency range from 7000 to 22,000 Hz and eliminates the dome break up of conventional drivers that can cause resonance and harsh, metallic sound.

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 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-424 is designed for ease of installation. The MHV-1090 components come pre-assembled to reduce field assembly time. Three bolts are all that are required to secure the MHV-1090 to the top of the LF-4215 enclosure.

Features:

• Four-way selectable, tri or quad- amplified screen channel system
• Unique HF/VHF diaphragm has less mass than traditional diaphragms resulting in exceptional dynamic range, extended high frequency response and lower distortion
• LF-4215 is constructed of MDF and is heavily braced
• Low-distortion waveguides provide highly articulate dialogue
• Shallow depth (20-inch) facilitates installation

Specifications:

• SC-424:
  • Nominal Coverage: 90° horizontal by +20 to -30° vertical
  • Frequency Range: (-6 dB) 33 Hz–20 kHz
  • Active Crossover Frequencies: 250, 1700, and 6000 Hz, 24 dB per octave
• LF-4215:
  • Impedance: 4 ohms
  • Sensitivity:
    • 1 watt/1 meter, half space: 99.5 dB
    • 8 hours of 6 dB crest factor IEC 268 noise spectrum: 800 watts continuous
    • 2 hours of 6 dB crest factor pink noise, 50 Hz–20 kHz, AES method: 1000 watts continuous
  • Recommended Amplifier Power: 1600 watts continuous maximum
  • Power Handling:
    • MF: 800 W continuous
    • HF: 500 W continuous
    • VHF: 300 W continuous maximum
  • Recommended Processing: Subsonic filter below 30 Hz, >18 dB per octave
  • Connectors: Barrier strip screw terminals accept up to #10 AWG stranded wire
  • Drivers:
    • Two 15-inch (381mm) high efficiency, extended bass woofers featuring 4-inch copper voice coils
  • Enclosure:
    • Quasi B4 alignment, ported enclosure with fully flared ports
    • Symmetrical port design, tuned to 36 Hz
    • Constructed of MDF and heavily braced
    • Features vandal-resistant woofer mounting bolts
  • Dimensions:
    • HWD (inches): 36 × 30 × 20.3
    • HWD (mm): 762 x 910 x 516
  • Weight:
    • Net Weight: 84 lb (38.5 kg)
    • System Weight: 256 lb (116 kg)
  • Baffle Cut-Out: 76-inch × 32-inch
• MHV-1090:
  • Impedance:
    • MF: 8 ohms
    • HF: 8 ohms
    • VHF: 8 ohms
  • Sensitivity (1 watt/1 meter, half space):
    • Tri-amp:
      • MF: 105 dB
      • HF/VHF: 110 dB
    • Quad-amp:
      • MF: 105 dB
      • HF: 110 dB
      • VHF: 110 dB
  • Power Handling (2 hours of 6 dB crest factor pink noise, 50 Hz–20 kHz, AES method):
    • Tri-amp:
      • MF: 275 W continuous
      • HF/VHF: 200 W continuous
    • Quad-amp:
      • MF: 275 W continuous
      • HF: 100 W continuous
      • VHF: 100 W continuous
  • Recommended Amplifier Power:
    • MF: 800 W continuous
    • HF: 500 W continuous
    • VHF: 300 W continuous maximum
  • Recommended Processing: 4th order LR crossover at 250, 1700, and 6000 Hz via QSC processing
  • Connectors: Barrier strip screw terminals accept up to #10 AWG stranded wire
  • Transducers:
    • MF: 10-inch high-efficiency, horn-loaded cone with phase plug
    • HF/VHF: coaxial neodymium compression driver with 3.5-inch (90 mm) HF diaphragm and 1.75-inch (44 mm) VHF diaphragm
  • Enclosure:
    • Tilt/Pan Bracket:
      • ± 10° vertical tilt
      • ± 10° horizontal pan
  • Dimensions:
    • HWD (inches): 39 × 30 × 20
    • HWD (mm): 762 x 990 x 508
  • Net Weight: 84 lb (38.5 kg)