The MartinLogan Subwoofer Control App uses a Bluetooth connection to simplify setup and configuration of compatible MartinLogan subwoofers. App based controls include volume level, low-pass filter (frequency and order), phase, 20–30Hz level, three preset listening modes, and control of Anthem Room Correction. A unique tone sweep feature assists users in locating areas in listening rooms where troublesome rattles or resonances may occur. A single press of a button allows listeners to initiate a