Check the listing for details. Infinity PRIMUS-3000A Primus 1-Channel, 250w X 1 Subwoofer amplifier. Condition: New. Listed at 90.00 USD. Infinity Primus Amps are available in a variety of configurations, delivering the right power and number of channels for full-range and subwoofer applications. For more than four decades, Infinity has made the audio experience a lot more satisfying for the car audio enthusiast. With a broad array of loudspeakers, amplifiers and subwooers available, you can drive with ease and exhilaration. These compact amps are equipped with all the important inputs and user controls including a bass EQ as well as LPF and HPF crossover controls for tailoring sound to suit the characteristics of different vehicles. The Primus Amps are easily installed and amazingly reliable - and once they turn on, they'll make a transducer sit up and sing.