PowerBass ASA3-1500.1D 1,500w rms @ 1 - Ohm mono block class-d amplifier To give your subwoofers some serious power at an affordable price, we offer the ASA3 range in super efficient Class D power. This line offers amplifiers that can provide up to 1,500 watts to a single woofer. PowerBass's ASA3 Class D amplifiers are always 1-ohm stable, and still come complete with all our sought after features like subsonic filters to keep ultra low frequencies from zapping power from frequencies that you do not want to reproduce and protection circuitry that will keep your amplifier from blowing up during duress.