CX254

4-Channel Low-Z Power Amplifier


Features

  • Compact size — only 2 RU and 14" deep for reduced rack cost and floor space
  • Bridgeable channels 1 + 2 and 3 + 4, for maximum flexibility
  • Active inrush limiting eliminates AC inrush current, removing the need for expensive power sequencers
  • HD15 DataPort connector for Q-SYS networked control and monitoring
  • Custom integrated security cover for tamper-proof installations
  • Variable-speed fan for low noise
  • 1-dB detented gain controls for fast and accurate gain settings
  • Detachable Euro style input connectors
  • DIP switch control for clip limiters, high pass filters, bridge mono and parallel operation
  • Exclusive PowerLight switch-mode power supply technology for high performance and compact size
  • Selectable high-pass filters protect speakers and prevent speaker transformer saturation with minimal effect on program material (33 Hz or 75 Hz)
  • Comprehensive front panel indicators including signal, clip, protect and QSC's exclusive bridge mono and parallel input LEDs
  • Barrier strip output connector
  • Comprehensive protection circuitry including DC, infrasonic, thermal overload and short circuit protection
  • High-performance Class AB+B complementary bipolar output circuitry
  • Lightweight—all models only 21 pounds (9.5 kg) for easier racking and shipping
  • 3-year warranty plus optional 3-year extended service contract
  • All CX Series amplifiers meet the European Union's, 2006 RoHS directive to restrict the use of hazardous materials used in electronic devices.
SPECIFICATIONS CX204V CX254 CX404
  POWER PER CHANNEL, STEREO MODE (all channels driven)
8Ω, 20 Hz–20 kHz 0.05% THD - 170 W 250 W
4Ω, 20 Hz–20 kHz 0.05% THD - 250 W 400 W*
2Ω, 1 kHz 1% THD - 450 W not recommended
70 V, 20 Hz–20 kHz 0.05% THD 200 W - -
70 V, 1 kHz 0.05% THD 220 W - -
70 V, 1 kHz 1% THD 300 W - -
  POWER, BRIDGED MONO MODE
16Ω, 20 Hz–20 kHz 0.1% THD - 340 W 500 W
8Ω, 20 Hz–20 kHz 0.1% THD - 500 W 800 W*
4Ω, 1 kHz 1% THD - 900 W not recommended
140 V, 20 Hz–20 kHz 0.1% THD 400 W - -
140 V, 1 kHz 0.05% THD 440 W - -
140 V, 1 kHz 1% THD 600 W - -
Noise, 20 Hz–20 kHz >106 dB >106 dB >105 dB
Input Sensitivity 1.26 V rms 1.22 V rms 1.22 V rms
Maximum Voltage Gain 35 dB 29 dB 31 dB
Input Clipping 10 V rms (+22 dBu) 10 V rms (+22 dBu) 10 V rms (+22 dBu)
Output Circuitry Class AB+B AB+B AB+B
Distortion (SMPTE-IM) Less than 0.02% Less than 0.01% Less than 0.01%
  ALL MODELS
Distortion (Typical)
20 Hz–20 kHz: 10 dB below rated power
1.0 kHz and below: full rated power

Less than 0.01% THD
Less than 0.01% THD
Frequency Response (typical) 20 Hz–20 kHz, ± 0.2 dB 8 Hz–50 kHz, +0/-3 dB
Damping Factor
Greater than 500 (1 kHz and below)
Input Impedance
6 kΩ unbalanced, 12 kΩ balanced
Cooling
Variable speed fan, rear to front airflow through tunnel heat sink
Connectors, each channel
Input: 3 position Euro-style detachable barrier block, channels 1, 2, 3, 4
DataPort: two HD-15 connectors—Ch 1+2, Ch 3+4
Output: Six-position barrier strip with monitor connections, Ch 1+2, Ch 3+4
Amplifier Protection
Full short circuit, open circuit, thermal, ultrasonic, & protection. Stable into reactive or mismatched loads.
Load Protection
On/off muting, DC-fault power supply protection
Indicators
PARALLEL INPUTS: Red LED
BRIDGED: Yellow LED
PWR-ON: Green LED
CLIP/PROT: Red LED (1 per channel)
LEVEL-10 dB: Yellow LED (1 per channel)
LEVEL-20 dB: Yellow LED (1 per channel)
SIGNAL -35 dB: Green LED (1 per channel)
Controls
Controls Front: AC switch, four gain knobs
Rear: Two DIP switch gangs—channels 1 and 2; channels 3 and 4: clip limiter on/off, LF filter on/off, LF filter freq select 33 Hz or 75 Hz for non-V models; 50 Hz or 75 Hz for V models; inputs parallel or stereo; bridge mode
Dimensions
19" (48.3 cm) rack mounting, 3.5" (8.9 cm) tall (2 rack spaces),
14" (35.6 cm) deep (from front mounting rails)
Weight
21 lb (9.5 kg) net, 27 lb (12.3 kg) shipping
Power Requirements
100, 120, 230 V AC, 50–60 Hz