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ZAPCO Mono Class AB Amplifier for High Power Sound

ZAPCO Mono Class AB Amplifier for High Power Sound

Regular price $299.00
Regular price $299.00 Sale price $299.00
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Zapco ST-1B Mono Class AB Amplifier

Serious subwoofer power. Serious sound quality.

The Zapco ST-1B is a mono Class AB amplifier built for one job: delivering clean, distortion-free power to your subwoofer system. No compromises, no current limiting, no shortcuts—just pure Zapco engineering with 40 years of audio heritage backing every watt.

Why the ST-1B?

This isn't a budget amp. The ST-1B is engineered for audiophiles and serious car audio enthusiasts who refuse to sacrifice sound quality for power. Unlike Class D amps that prioritize compact size, the ST-1B uses Class AB topology to deliver superior dynamic range and sonic purity. That means your bass hits harder, stays cleaner, and never sounds compressed—even at full volume.

Key advantages:

  • Superior dynamic range – More headroom between quiet passages and peak power without distortion
  • Class AB efficiency – Optimized for sound quality over size
  • Flexible wiring – Run one 2Ω sub or two 4Ω subs from the same amp
  • Full control – Variable gain, bass boost (0–12dB), phase control (0–180°), and subsonic filter
  • Professional installation – RCA inputs/outputs, remote control port, and clean integration

Built for Real-World Installs

The ST-1B integrates seamlessly into any car audio system. Pass-through RCA outputs let you daisy-chain additional amps, while the subsonic filter eliminates frequencies below your sub's capability—protecting your equipment and tightening your bass response. The variable low-pass crossover and phase control give you precise tuning for any vehicle acoustics.

Installation-ready features:

  • MOSFET power supply for stable, clean power delivery
  • Variable input gain control (set to minimum before initial turn-on)
  • 0–180° phase adjustment for perfect integration with front speakers
  • Subsonic filter to protect your subwoofer and reduce cabin resonance
  • Remote control port for convenient gain adjustment from the driver's seat

Specifications

Spec Value
Type 1-Channel Class AB Amplifier
Power @ 4Ω 200 watts RMS
Power @ 2Ω 300 watts RMS
THD < 0.2% (extremely clean)
Signal-to-Noise Ratio > 90dB
Frequency Response 15Hz–30KHz ±1dB
Input Sensitivity 0.25V–5V (adjustable)
Dimensions (net) 182(W) × 52(H) × 280(L) mm
Dimensions (overall) 182(W) × 52(H) × 310(L) mm

Installation Notes

The ST-1B requires adequate ventilation—mounting in the trunk with airflow is ideal. Always use proper power and ground wire sizing (consult the included wire sizing chart based on your installation distance). A fuse or circuit breaker within 18" of the battery is essential for safety.

Wiring flexibility:

  • Single 2Ω subwoofer minimum
  • Two 4Ω subwoofers minimum each
  • RCA or high-level (speaker-level) inputs

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Zapco ST-1B mono amplifier: 200W @ 4Ω / 300W @ 2Ω Class AB subwoofer amp. Superior sound quality, variable crossover, phase control & subsonic filter. Professional car audio installation.

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