The Earthquake Sound SLAPS-M8v2 is a tunable passive bass radiator that significantly increases subwoofer efficiency and ability for ultra-low frequency reproduction without additional amplifier power or enclosure volume. Designed to perfectly complement all good quality long throw woofers on the market, SLAPS add up to +6dB of bass compared to regular sealed and ported enclosures. The benefit of SLAPS being user-tunable is that they can be integrated into virtually any subwoofer/enclosure combination. SLAPS (Symmetrically Loaded Audio Passive System) overcomes the limitations known from the conventional sealed and ported enclosures that tend to limit excursion. As the name indicates, SLAPS is built symmetrically, distinguishing it from traditional or other inferior passive devices on the market today. SLAPS technology integrates a dual structure of identical opposites in its suspension design, resulting in identical properties in both the negative and positive pressure domains. The high efficiency and performance are a result of the pneumatic coupling between SLAPS and an active driver. SLAPS's unique and patented design allows the active driver compression-free excursion, resulting in a deep, dynamic, and powerful bass response.