Presonus Temblor T10 10" 250 Watt Active Studio Reference Subwoofer Sub Presonus Temblor (T10) 250 Watt / 175 Watt RMS Active Studio Subwoofer 10-inch glass-composite low-frequency transducer Front-firing, bass-reflex acoustic port Input gain control (-30 dB to +6 dB, continuously variable) Continuously variable lowpass filter (50 Hz to 130 Hz)