The RP-400Ms may be the smallest bookshelf speakers in Klipsch's new Reference Premiere lineup. But these compact gems offer dynamic sound that brings music to life without taking up much space in your room. Each one features a 4" spun-copper woofer for punchy bass and midrange, and Klipsch's signature 1" horn-loaded tweeter for smooth, detailed highs and a "front row" listening experience.