Alpine SWJ-12S4 J-Series 12″ Subwoofer (250W RMS / 750W Peak)

Upgrade your car audio system with the Alpine SWJ-12S4 J-Series 12″ Subwoofer, engineered to deliver deep, impactful bass with high efficiency and durability. Designed as part of Alpine’s entry-level performance series, this subwoofer is ideal for users looking to add strong low-end punch without heavy investment.

Featuring a 12-inch large driver with a 4-ohm voice coil, the SWJ-12S4 produces tight bass response, improved air movement, and better sound pressure, making it perfect for bass-heavy music and daily listening setups.

🔊 Key Features

✔ 12″ High-Performance Subwoofer – Large cone area delivers deeper and more powerful bass

✔ 250W RMS / 750W Peak Power – Strong and controlled bass output for daily use

✔ Polypropylene + Mica Cone – Lightweight yet rigid construction for accurate bass reproduction

✔ Poly-Foam Surround – Enhances cone movement and durability for long-term use

✔ Wide Frequency Response (≈22Hz – 200Hz) – Covers deep low frequencies for powerful bass

✔ 4 Ohm Impedance – Compatible with most mono amplifiers and standard setups

✔ High Efficiency Design – Delivers strong output even with moderate power amplifiers

✔ Budget-Friendly Performance – Ideal for entry-level to mid-range audio upgrades

🔧 Technical Specifications

• Model: SWJ-12S4 (J-Series)
• Subwoofer Size: 12 Inch (30 cm)
• RMS Power: 250 Watts
• Peak Power: 750 Watts
• Frequency Response: ~22Hz – 200Hz
• Impedance: 4 Ohm
• Cone Material: Polypropylene + Mica
• Surround: Poly-Foam
• Mounting Depth: Approx. 135 mm

📦 Package Includes

• 1 × Alpine SWJ-12S4 Subwoofer
• Mounting Accessories
• User Manual

🚗 Why Choose Alpine SWJ-12S4

• Strong deep bass output with large 12″ driver
• Reliable Alpine build quality
• Perfect for entry-level bass upgrades
• Works well with mono amplifiers (250–400W range)
• Ideal for SUVs, sedans & hatchbacks with boot space

🛠 Installation Notes

• Requires external amplifier for operation
• Best performance in sealed or ported enclosure box
• Recommended sealed box: ~1.0 cu.ft / ported box: ~1.8 cu.ft
• Professional installation recommended for tuning and enclosure setup