Sundown Audio SDX-100.4 4-Channel Weatherproof Amplifier
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Subwoofer Wiring Diagram
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- Power — 100W x 4 @ 4Ω, 135W x 4 @ 2Ω, 270W x 2 @ 4Ω bridged
- Class — Class-D, 4-channel, water-resistant
- Filters — Variable 12dB HPF/LPF with x1/x20 multiplier, bass boost @ 50Hz
- Build — Heavy cast aluminum heat sink, removable control cover
- Protection — Thermal, voltage, speaker short, DC-offset
This Listing Includes: (1) Sundown Audio SDX-100.4 4-Channel Weatherproof Amplifier
The water-resistant SDX-100.4 is a compact Class-D amplifier built for cars, UTVs, and open-air vehicles, delivering 100 watts x 4 at 4 ohms, 135 watts x 4 at 2 ohms, or 270 watts x 2 bridged at 4 ohms. Channels 1–2 offer a variable 12dB high-pass filter (15Hz–500Hz or 300Hz–10kHz), while channels 3–4 add variable 12dB high-pass (15Hz–500Hz) and low-pass (30Hz–500Hz or 600Hz–10kHz) filters, all with x1/x20 frequency multipliers and a variable 12dB bass boost at 50Hz. DC auto-sensing turn-on, a sealed removable control cover, and a robust cast aluminum casing provide easy setup, heat dissipation, and weather protection, backed by thermal, voltage, speaker-short, and DC-offset circuitry. To access audio settings, unscrew the badge with an allen key. Authorized Sundown Audio dealer at JS Ultimate Sounds. Free shipping on orders $99+.
Features
- Water-resistant Class-D design for powersports and daily drivers
- Ch. 1–2 variable 12dB high-pass: 15Hz–500Hz or 300Hz–10kHz
- Ch. 3–4 variable 12dB high-pass (15Hz–500Hz) and low-pass (30Hz–500Hz or 600Hz–10kHz)
- x1/x20 crossover frequency multipliers with variable 12dB bass boost @ 50Hz
- Heavy cast aluminum heat sink with removable control cover and optional wired remote
Specifications
| RMS @ 4Ω | 100W x 4 |
| RMS @ 2Ω | 135W x 4 |
| RMS @ 4Ω Bridged | 270W x 2 |
| Class | D |
| High-Pass Filter (Ch. 1–2) | 15Hz–500Hz or 300Hz–10kHz (12dB) |
| High-Pass Filter (Ch. 3–4) | 15Hz–500Hz (12dB) |
| Low-Pass Filter (Ch. 3–4) | 30Hz–500Hz or 600Hz–10kHz (12dB) |
| Crossover Multiplier | x1/x20 |
| Bass Boost | 12dB @ 50Hz |
| Weatherproofing | Water resistant |
| Protection | Thermal, voltage, speaker short, DC-offset |
