Soundstream ST4.1200D is a car audio amplifier for an aftermarket vehicle audio installation. Match the specifications, connections and mounting requirements below to your system before ordering.

• Brand: Soundstream
• Manufacturer part number: ST4.1200D

Key specifications

• Max Power: 1,000 Watts
• RMS Power 4Ω: 100W x 4
• RMS Power 2Ω: 150W x 4
• Amplifier Size: 3″W x 1.50″H x 7.75″L

Features and installation details

Stealth Series 4Ch Micro-Amp

The Soundstream Stealth Series ST4.1200D amplifiers may be small in size, but don’t let their compact design fool you. These little monsters pack an incredible punch, thanks to Class D full-range technology. With the latest advancements in Class D amplification, the ST4.1200D delivers high power in a less than 2-pound chassis, offering you more power than you'd expect from such a compact device.

Small in Size, Big on Performance

The ST4.1200D is designed with Class D technology, a revolutionary advancement that was once considered "dirty power" but has now become a benchmark for stability and efficiency. With high power capability, maximum efficiency, and low tolerance components, Class D amplifiers have surpassed traditional full-range amplifiers in delivering reliable, clean sound. The ST4.1200D provides stable and consistent performance, even when driving high-demand car audio systems, subwoofers, or speakers.

Despite its small size, this amplifier delivers an impressive 1200W of power, making it ideal for car audio systems, motorcycle setups, boat systems, and off-road vehicles. Its ultra-micro footprint ensures it can fit in tight spaces, while its unbelievable sound quality brings an extra dimension to your audio setup, whether you're cruising down the highway, tearing through the trails, or sailing on the water.

Maximum Efficiency and Minimal Power Requirements

The ST4.1200D amplifier operates with minimal power requirements, meaning it uses less energy to produce more sound. This efficiency not only helps with power conservation but also reduces heat, ensuring long-lasting, reliable performance. The low-profile design of the amplifier helps with installation, and its compact size makes it a perfect choice for custom audio builds or vehicle systems where space is limited.

Perfect for Custom Installations

The Soundstream Stealth Amplifier is incredibly versatile, making it a great choice for various audio systems. Whether you're upgrading your factory-installed stereo or building a custom setup, the ST4.1200D offers easy installation. Its compact design allows it to fit seamlessly into most spaces in vehicles, boats, motorcycles, or off-road setups, ensuring you don’t have to sacrifice performance for size.

The automatic hi-level signal sensing turn-on feature eliminates the need to run a remote wire turn-on. The amplifier detects the audio signal from your head unit and automatically powers on and off, making it perfect for systems using factory radios or OEM installations. This means you don’t have to worry about complex wiring or additional connections—just plug it in and enjoy powerful audio.

Key Features of the Soundstream Stealth ST4.1200D:

• 1200W of Power: Compact design delivers impressive output.
• Class D Full-Range Technology: High efficiency with low power consumption.
• Automatic Hi-Level Signal Sensing Turn-On: No need for a remote wire—automatically turns on when it detects an audio signal.
• Ultra-Compact Design: Fits easily in space-constrained installations without sacrificing performance.
• Stable Performance: Delivers clean, distortion-free sound even under high power.
• Versatile Applications: Ideal for car audio systems, motorcycle setups, boat audio systems, and off-road vehicle audio installations.
• Easy Installation: Simplified setup with RCA and hi-level inputs.
• Low-Profile, High-Efficiency Design: Minimal power requirements and reduced heat for long-lasting performance.

Built for Any Audio Setup

Whether you’re a car audio enthusiast or looking to upgrade your motorcycle, boat, or off-road audio system, the Soundstream Stealth ST4.1200D amplifier is designed to deliver exceptional sound across a variety of applications. It’s perfect for people who need reliable power in a compact form without compromising on sound quality.

In Summary:

• 1200W Class D 4-Channel Amplifier designed for compact, high-efficiency audio setups.
• Automatic Hi-Level Signal Sensing Turn-On for easy installation with no remote wire.
• Perfect for car audio, motorcycle setups, boat systems, and off-road vehicles.
• Class D technology offers stable performance with low heat and maximum output.
• Easy to install with hi-level input and RCA input options.
• Versatile power output suitable for various speaker and subwoofer setups.

Stealth Amplifier Features:

High-Efficiency Class D Full-Range Amplifiers

Hybrid Aluminum Alloy Heatsink for Optimum Dissipation

2-ohm Stereo & 4-ohm Bridged Full-Range Operation

MOSFET Power Supply w/ Audiophile Grade IRTM Transistors

Military Grade SMT PCB Maintains Dynamic Performance

Direct Short, Thermal, & Overload Circuits Protect Amplifier

200mV-12V High Level or Low-Level RCA Input

Automatic Turn-On Hi-Level Signal Sensing

Quick Disconnect RCA/High-Level Wire Harness

Quick Disconnect Power and Speaker Output Harness

Variable 12dB High Pass, Low Pass, & Subsonic Crossovers

Amplifier Dimensions 3"W x 1.5"H x 7.75"W

Stealth Amplifier Owners Manual [.PDF]

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