S, high quality drivers and a decent amplifier. The m20 uses a response 3"driver and a 6"subwoofer in wood cabinets. Wood is much more effective dampening back wave transmission than plastic. The amplifier doesn't skimp on parts. The result is a surprising quality of sound for the price. The volume control is located on light cord that extends from the speaker making allowing you to make adjustments easily at any time. Amplifiers system Rated power 50w rms Frequency range 20hz-120hz Signal-to-noise