As you know, isolation transformer in the sound is very necessary equipment, it significantly improved its share (POWER). However, the power grid noise of them still need a lot of parts and noise filtering for AC power to the machine is clean equipment only help amplify sounds but do not amplify noise and noise energy loss.
This is the optimal solution to help you get the energy to just clean moderately strong. With the lowest cost and most succinct. Noise filter integrated in this machine is proactive interference filter.