DESC: The new Class D series from Power Acoustik is made for bass! The new A1800DB breaks all the cost-to-power boundaries with its cutting-edge class D design and insane power capabilities. A built-in low pass crossover with variable frequency control eliminates the need for an external crossover and makes the A1800DB ideal for driving your subwoofers with clean Power Acoustik power. Other features include variable subsonic filter to help protect your subs, 0-180 degree phase control for tight, accurate bass, 1-ohm stability, and gold-plated terminal-block connectors. A heavy-duty aluminum alloy heatsink gives these amps a distinctive, rugged look while still maintaining a compact footprint.