Pioneer GM-A6704 4 Channel Bridgeable Car Audio Speaker Sub Amplifier 380w RMS GM-A67044-Channel Bridgeable Amplifier (1000W)Amplify your audio experience.Give into your deepest desire for power. 4-channel combine impressive power with big sound for a loud, clear and distortion-free music experience Variable HPF Variable HPFadjust your high-pass filter frequency for greater audio system flexibility Variable LPF Variable LPFadjust your low-pass filter frequency for greater audio system flexibility.
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