Bass and Treble ControlSMSL Audio Stereo Amplifier This all-in-one amplifier is also equipped with a digital equalizer with multiple functions (bass tuning, treble, etc. ), built-in SMSL patented sound effect SDB, SDB can effectively improve the sound restoration, while dynamically adjusting the high and low sounds according to the current music signal. SMSL AD18 chipFull digital amplifier is part of the new generation of FDA all-digital amplifiers. It uses high-tech TAS5508C and TAS5342 chips using Texas Instruments (TI) digital pure path technology. The amplifier has the characteristics of "all-digital", compact design, high sound quality and high resolution, bringing a wonderful experience to music lovers.