Modular Power Conditioner Cleans Up Your Mains Power Supplies, Cancels Noise Across Upper and Lower Frequencies: Active iFi AC iPurifier Also Offers Ground, Polarity, and Surge Protection Clean up your mains power with the iFi AC iPurifier , an active power conditioner that cancels noise across both the upper and lower frequencies - and offers ground, polarity, and surge protection. Modularly designed to be used in multiples to target every noise source, iPurifier utilizes a wireless purification system that works with no side effects and iFi's patented Active Noise Cancellation technology. Simply insert AC iPuriifer into your AC mains wall outlet or insert one (or two) into your power block. You can actually plug one into each location for even better results. AC iPurifer also boasts an intelligent ground connection, intelligent polarity with a handy LED lighting indication system, and overage surge protection to guard against voltage spikes and lightning strikes. Read more on the individual features below, but know that for less than $100, AC iPurifier is a no-brainer addition to your system - and backed by our 100% Music Direct Satisfaction Guarantee . Wireless Purification System iFi's Wireless Purification System (WPS) is a complex circuit that reduces power-line noise without audible or measured side effects. This is important because such solutions, while attempting to curb noise, can also hamper dynamics, an issue AC iPurifier avoids. Smart Polarity and Earth Detection When it comes to mains AC, people make two common errors when setting up a system. The first has to do with polarity and the incorrect orientation of USA and EU type mains pins. Intelligent polarity automatically informs you of incorrect orientation by changing to a red LED. The second error is the a lack of a ground/earth. In a system where there may or may not be a lack