The roughly palm-sized 2-channel mini power amplifier QUANTUM QM-TWO amazed ESX fans and experts in the car hi-fi scene as soon as it was introduced. After the improved V2 version topped that again last year with an incredible 300 W RMS power, ESX is now following up with two more models in the QM class: The powerful QM-FOUR power amplifier is now available for 4-channel applications, and anyone who wants to drive a separate subwoofer can now choose the new QM-ONE monoblock.
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