QSC ISA450 2-Channel 260W Power Amplifier

The ISA Installed System Amplifiers are designed to meet the needs of sound system designers and contractors worldwide. Three models feature isolated 25, 70, and 100-volt outputs for distributed sound systems, while four low impedance models are rated for 2 ohm operation.

QSC ISA450 Features

• Rear panel gain controls for tamper resistance; 2-dB detents allow for quick and repeatable settings.
• XLR and detachable Euro-style input connectors
• DataPort V2 for use with DPV2-compatible signal processing accessories (XC-3, SF-3, LF-3) and DSP-3/DSP-4 (with external power supply)
• Independent defeatable clip limiters for reduced distortion
• Selectable high-pass filters (30 Hz or 70 Hz) protect speakers and prevent speaker transformer saturation with minimal effect on program material
• Front panel LED indicators include power, signal, and clip
• Covered barrier strip output connectors for safety agency compliance
• Automatic on-demand variable-speed fan: quiet normal operation, with maximum cooling when needed
• Rear-to-front air flow helps keep equipment racks cool
• Stereo, bridge, or parallel operating modes
• Comprehensive protection circuitry including DC, infrasonic, thermal overload, and short circuit protection

• ISA450 2-Channel 260W Power Amplifier1
• Three Year Warranty plus optional 3-year extended service contract1

• OUTPUT POWER PER CHANNEL, STEREO MODE, both channels driven
  • 8Ω, 20 Hz–20 kHz 0.1% THD: 260W
  • 4Ω, 20 Hz–20 kHz 0.1% THD: 425W
  • 2Ω 1 kHz 1% THD: 700W
• OUTPUT POWER, BRIDGED MONO MODE
  • 8Ω, 1 kHz 0.1% THD: 900W
  • 4Ω 1 kHz 1% THD: 1400W
• Signal to Noise (20 Hz-20 kHz)100dB
• Distortion (SMPTE-IM)Less than 0.01%
• Input Sensitivity @ 8 ohms1.07 V (+2.8 dBu)
• Maximum Voltage Gain44.7× (33 dB)
• Output CircuitryClass AB
• THX ApprovedYes
• Weight - Net36 lb (16.3 kg)
• Weight - Shipping42 lb (19.1 kg)
• Distortion (Typical) 20 Hz–20 kHz: 10 dB below rated powerLess than 0.03% THD, 4 ohms and 8 ohms
• 1.0 kHz and below: full rated powerLess than 0.03% THD, 4 ohms and 8 ohms
• Frequency Response 10 dB below rated output powerISA 280, 450, 750 and 1350: 20 Hz–20 kHz, +0/-1 dB; -3 dB points: 5 Hz and 50 kHz
• Damping Factor with 8Ω Load (direct outputs)Greater than 200; ISA 1350 greater than 250
• Output Regulation (isolated outputs)Less than 1.5 dB
• Input Impedance10 kΩ unbalanced, 20 kΩ balanced
• Input Clipping10 V rms (+22 dBu)
• CoolingContinuously variable speed fan, back-to-front air flow
• Connectors, each channel
  • Input: Active balanced; 3-pin Euro-style detachable terminal block and XLR (pin 2+)
  • Output: Covered barrier strips
  • DataPort V2: HD-15 connector
• Controls
  • Front: AC switch
  • Rear: Ch. 1 and Ch. 2 gain knobs, 10-position DIP switch
• Indicators
  • PWR-ON: Green LED; SIGNAL: Green LED (1 per channel);
  • CLIP: Red LED (1 per channel)
• Dimensions (HWD) inches5.25 x 19 x 15.9 / 3RU
• Dimensions (HWD) mm133 x 483 x 400 / 3RU
• Amplifier Protection
  • Full short circuit, open circuit, thermal, ultrasonic, and RF protection;
  • Stable into reactive or mismatched loads
• Power Requirements120 or 230 VAC, 50–60 Hz
• Load ProtectionOn/off muting; Triac crowbar: ISA 750, 1350, and 800Ti; AC coupling: ISA 280, 300Ti, 450, and 500Ti