Hifonics ZG-1800.1D Zeus Gamma Mono Class D Amplifier

The Hifonics ZG-1800.1D is a one-channel Class D amplifier designed for adding a dedicated subwoofer channel to a car audio system. It is intended for systems that need low-frequency amplification without using a large multi-channel chassis. Its mono configuration and 1-ohm stability provide flexibility when matching compatible subwoofer voice-coil wiring.

This amplifier is a practical choice for listeners upgrading factory or aftermarket audio systems with a separate bass stage. RCA inputs support aftermarket source units, while the included high-level input connection allows integration with many factory radios that lack RCA outputs. RCA outputs also allow the input signal to be passed to an additional amplifier.

The ZG-1800.1D is rated for 1 x 450 watts at 4 ohms, 1 x 900 watts at 2 ohms, and 1 x 1,800 watts at 1 ohm. A variable 40-300 Hz low-pass crossover, subsonic filter, bass boost, and phase adjustment help tailor the amplifier to the subwoofer and enclosure being used. The wired bass remote provides convenient level adjustment from the front of the vehicle.

Its power section uses Hifonics Simpatico Coil Design with a PWM MOSFET power supply, while Ultra-Fi output devices are used in the output stage. The Class D design is paired with an aluminum heat sink to manage heat in a compact amplifier format. A low-noise preamplifier circuit is designed to accept low-level source signals with minimal added distortion.

For a complete installation, this amplifier requires suitable power, ground, remote-turn-on, signal, speaker wiring, and a compatible subwoofer load. It accepts 4 AWG power and ground wire and uses an 80A fuse. It fits naturally into a system with a dedicated subwoofer enclosure and can be expanded through its RCA pass-through outputs.

Key Features

• Mono Class D Output: Delivers dedicated power for a compatible subwoofer system.
• 1-Ohm Stable Design: Supports properly wired loads down to 1 ohm.
• Variable Low-Pass Crossover: Helps keep bass frequencies routed to the subwoofer.
• High-Level Inputs: Allows connection to many factory radios without RCA outputs.
• Wired Bass Remote: Provides convenient bass-level adjustment from the driver area.
• Protection Diagnostics: Illuminated indicators help identify overload or speaker-short conditions.

Design & Installation

The ZG-1800.1D uses an aluminum heat sink, a Class D amplifier topology, and angled molded terminals for power, ground, and speaker wiring. Nickel-plated RCA input connections use hex screw terminals, while the PWM MOSFET power supply and Simpatico Coil Design support the amplifier's power section. The end panel includes LED system-protection diagnostics.

Mount the amplifier on a secure surface with adequate airflow and route power, speaker, and RCA cables carefully through the vehicle. Use 4 AWG cable at the power and ground terminals, an appropriately fused power run, and a compatible 1-, 2-, or 4-ohm subwoofer load. Set the input level, low-pass filter, subsonic filter, bass boost, and phase control during system tuning rather than using gain as a volume control.