Zapco ST-5B 5-Channel Class A/B Car Amplifier

Upgrade your car audio system with the powerful Zapco ST-5B 5-Channel Class A/B Amplifier, designed to deliver clean, dynamic sound while powering both speakers and a subwoofer from a single compact unit. Part of the Studio-B series, this amplifier combines Zapco’s legendary sound quality with versatile system integration features.

The ST-5B amplifier provides four full-range channels for speakers and a dedicated subwoofer channel, making it ideal for complete front-stage and subwoofer setups. With its MOSFET power supply, adjustable crossovers, and bass boost, the amplifier ensures powerful output with minimal distortion and precise sound control.

Whether upgrading factory speakers or building a custom sound system, the Zapco ST-5B offers reliable performance, excellent tuning flexibility, and strong power output for everyday car audio enthusiasts.

Key Features

✔ 5-Channel Class A/B Amplifier – Power four speakers and a subwoofer from a single amplifier.

✔ High-Quality MOSFET Power Supply – Provides stable and efficient power delivery for clean sound output.

✔ Variable Electronic Crossovers – Includes FULL / HP / LP crossover controls for precise tuning.

✔ Bass Boost Adjustment – Enhance low-frequency output for stronger subwoofer performance.

✔ RCA & High-Level Inputs – Compatible with both aftermarket and OEM head units.

✔ Compact Aluminum Chassis – Efficient cooling and easier installation in modern vehicles.

Power Output

• RMS Power @ 4Ω: 70W × 4 + 250W × 1

• RMS Power @ 2Ω: 100W × 4 + 400W × 1

• Bridged Power @ 4Ω: 180W × 2 + 400W × 1

This power configuration allows the amplifier to efficiently run front speakers, rear speakers, and a dedicated subwoofer channel in a single installation.

Technical Specifications

• Amplifier Type: Class A/B Full Range

• Channels: 5

• Frequency Response: 10 Hz – 30 kHz ±1 dB

• Signal-to-Noise Ratio: > 90 dB

• THD: < 0.2%

• Input Sensitivity: 0.25V – 5V

• Channel Separation: > 45 dB

• Dimensions: 182 × 52 × 351 mm

These specifications ensure clean sound reproduction with low distortion and excellent dynamic range.

Package Includes

• 1 × Zapco ST-5B Amplifier

• 1 × Bass Remote Controller

• Mounting Screws

• User Manual

• Warranty Card

Why Choose Zapco ST-5B

• Perfect single-amp solution for a full car audio system

• Clean Class-AB sound signature preferred by audiophiles

• Flexible tuning with crossover and bass boost controls

• Reliable build quality from Zapco’s Studio Series