Zapco - Z-150.4 SP - Class AB, 4-Ch Power 2Ω: 4 x 275W, 4Ω: 4 x 165W

The Zapco Z-150.4 SP is a high-performance Class AB 4-channel amplifier crafted for audiophiles seeking warmth, musicality, and precision. Delivering 275 watts RMS per channel at 2 ohms, it provides clean, dynamic power ideal for front-stage, rear-fill, or multi-way active systems. Built with Zapco’s signature analog circuitry, this amplifier offers stunning clarity, wide bandwidth, and rock-solid reliability — making it a perfect choice for sound quality competition and high-end installations.

• Model: Z-150.4 SP
• Type: Class AB 4-Channel Full-Range Amplifier
• Power Output (RMS):
 • 4 Ω Stereo: 4 × 165 W
 • 2 Ω Stereo: 4 × 275 W
 • 4 Ω Bridged: 2 × 550 W
• Frequency Response: 10 Hz – 30 kHz (±1 dB)
• Signal-to-Noise Ratio: > 100 dB
• THD + N: < 0.05% at rated power
• Damping Factor: > 200 @ 100 Hz
• Input Sensitivity: 0.25 V – 8 V (variable)
• Input Impedance: 20 kΩ (balanced) / 10 kΩ (unbalanced)
• Crossover Network (per channel pair):
 • High-Pass Filter (HPF): 15 Hz – 4 kHz (12 dB/octave)
 • Low-Pass Filter (LPF): 30 Hz – 4 kHz (12 dB/octave)
 • Band-pass configuration possible via dual filter setup
• Bass Boost: 0 – 12 dB @ 45 Hz (adjustable)
• Protection Circuits:
 • Thermal overload
 • Short circuit
 • DC offset
 • Over/under voltage
• Cooling System: Heavy-duty aluminum heatsink with temperature-controlled fan assist
• Fuse Rating: 2 × 60 A
• Power Supply: Fully regulated MOSFET PWM design
• Dimensions: 17.3″ (L) × 8.5″ (W) × 2.5″ (H)
• Weight: Approx. 12.1 lb (5.5 kg)
• Included Accessories: Mounting hardware, user manual