Non-pressed paper cone: Pioneer carefully selects materials and applies a non-pressed paper process-giving these new cones the light, rigid qualities needed to create punchy, powerful sound and extra durability to go to the limit. Lightweight copper-clad aluminum wire voice coil allows for faithful reproduction of louder sounds. Dual layer urethane sound: New dual layer minimizes unnecessary cone resonance for higher cone durability and clearer sound. P.F.S.S. Spider: Achieves the best balance between sound quality and high durability, this system realizes ideal sound reproduction. Gold plated terminals are excellent conductors with very less loss of energy (sound), preferred by audiophiles. Film cone tweeter: To reproduce sound clearly with outstanding responsiveness. Buttress ring: Helps the woofer to reproduce bass sound without any loss under the heavy usage (the high volume input)