Sundown SIA-1250D Full-Range Mono Amplifier
1250 W at 1 or 2 ohms with Smart Cooling fan
$219.99$269.99 (-19%)
Overview
The Sundown SIA-1250D is a full-range mono Class D amplifier rated 1250 W RMS at both 1 ohm and 2 ohms, and 800 W at 4 ohms. An advanced three-speed Smart Cooling fan, heavy heatsink, and wired remote with clipping indicator support sustained high-power use. Recommended fuse rating is 120 A with 1/0 AWG input wire.
Product details
Same power at 1 and 2 ohms
RMS ratings are 1250 W @ 1 Ω, 1250 W @ 2 Ω, and 800 W @ 4 Ω. The intelligent full-bridge design targets stable output across those loads.

Smart Cooling and filters
A three-speed Smart Cooling fan and heavy heatsink manage heat. Variable 12 dB LPF (40 Hz–20 kHz), HPF (10 Hz–1 kHz), subsonic filter, and bass boost at 50 Hz cover tuning needs.

Power planning
Plan a 120 A fuse and 1/0 AWG power input. Chassis size is about 5.71 × 7.28 × 2.44 inches. A wired remote with clipping indicator is included.
Key features
- 1250 W RMS @ 1 Ω and @ 2 Ω
- 800 W RMS @ 4 Ω
- Full-range Class D mono (full bridge)
- Three-speed Smart Cooling fan
- Variable LPF 40 Hz–20 kHz (12 dB)
- Variable HPF 10 Hz–1 kHz (12 dB)
- Subsonic filter and bass boost @ 50 Hz
- Wired remote with clipping indicator
- Fuse rating 120 A; 1/0 AWG input
Specifications
| Weight | 5.2 lbs |
|---|---|
| Dimensions | 7.28 × 5.71 × 2.44 in |
| Channels | Mono |
| Brand | Sundown |
| Model | SIA-1250D |
| SKU | SIA1250D |
| UPC | 810111130592 |
| Product type | Mono amplifier |
| Channels | Mono |
| Class | D (full bridge) |
| RMS @ 1 Ω | 1250 W |
| RMS @ 2 Ω | 1250 W |
| RMS @ 4 Ω | 800 W |
| Fuse rating | 120 A |
| Input wire | 1/0 AWG |
| Dimensions | 5.71 × 7.28 × 2.44 in |
| Cooling | 3-speed Smart Cooling fan |
Important notes
- Use 120 A fusing and 1/0 AWG power/ground as specified
- Make sure speaker impedance before final wiring
- Professional installation recommended
What's in the box
- Sundown SIA-1250D amplifier
- Wired remote control
- Mounting hardware as packaged





