Soundstream ST4.500D 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: ST4.500D

Key specifications

• Max Power: 500 Watts
• RMS Power 4Ω: 45W x 4
• RMS Power 2Ω: 65W x 4
• RMS Bridged 4Ω: 125W x 2
• Dimensions (3”w x 1.5”h): 3.75”

Features and installation details

Stealth Series 4Ch Micro-Amp

As if harnessing power into the original Stealth amps wasn’t enough, the Soundstream ST4.500D takes the mini amp game to the next level. Packed into an ultra-compact 3” chassis, this 4-channel amplifier uses advanced integrated circuit Class D full-range technology to deliver high-quality power output in the smallest possible form factor.

Designed for stealth installs, motorcycles, UTVs, and tight spaces, the ST4.500D offers flexibility without compromise. It’s the ultimate answer for those who demand serious performance in a small footprint.

Compact Design, Serious Power Output

High-Efficiency Class D Circuitry

Built with Class D full-range technology, the ST4.500D ensures efficient power handling and reduced heat, ideal for prolonged use in limited space environments. Whether you're powering door speakers or midrange drivers, this amp delivers clean output without distortion.

500W Peak Performance

With 500 watts of max power, this mini 4-channel amplifier handles anything from factory replacements to upgraded speaker systems. It bridges seamlessly into 2-channel mode, offering more power flexibility for subwoofer or rear fill configurations.

Smart Integration for Any Audio Setup

Universal Hi-Level Input with Auto Turn-On

Are you using an original or factory radio? No problem. The ST4.500D features Automatic Hi-Level Signal Sensing Turn-On. This eliminates the need for a separate remote wire—just plug in the hi-level inputs, and the amplifier powers on or off based on audio signal detection.

Versatile Audio Signal Compatibility

Accepts both hi-level and low-level audio signals, making it perfect for integration with OEM or aftermarket head units. No matter your setup, this amp blends seamlessly into your system.

Compact Body, Complete System Controls

Adjustable Pre-Amp Crossovers

Each channel is equipped with built-in pre-amp crossover controls, allowing tailored tuning for each speaker zone. Fine-tune your front and rear channels independently for a balanced and immersive in-car sound experience.

Perfect for Tight Installs

At just 3 inches in height, the ST4.500D is a stealth install specialist. Mount it under seats, behind panels, or in glove compartments without sacrificing cabin space or ventilation.

Stealth Shot Series – Purpose-Built Power

The ST4.500D is part of Soundstream’s Stealth Shot series, which includes:

• Quad Shot – 4-channel model (this product)
• Double Shot – 2-channel variant
• Single Shot – Monoblock amp

Each is engineered to deliver top-tier sound in the most compact builds available.

Stealth Shot Amplifier Features:

Hybrid Aluminum Alloy Heatsink for Optimum Dissipation

2-ohm Minimum Impedance Operation

MOSFET Power Supply w/ Audiophile Grade IR^TM Transistors

Military Grade SMT PCB Maintains Dynamic Performance

Direct Short, Thermal, & Overload Circuits Protect Amplifier

250mV-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

Full Variable 12dB High Pass, Low Pass Crossovers

Amplifier Dimensions 3"W x 1.5"H x 3.75"W

Stealth Shot Amplifier Owners Manual [.PDF]

More from Soundstream

Explore these related options. Compare specifications and vehicle fitment when choosing an alternative or planning an installation.

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