The all-new HD25 Bass Combo packs Hartke's patented HyDrive speaker technology into a sleek combo design ideal for small venues, rehearsal spaces and bedroom practice sessions, and capable of greatly enriching your low-end tone. The HD25 also maintains Hartke's commitment to producing high-quality bass amplification with exceptional durability. The HyDrive Design The HD25 (25 watts, 8" driver) employs Hartke’s patented HyDrive Speaker Technology that offers a carefully crafted hybrid (half paper, half aluminum) cone bass speaker. By combining the warmth and roundness of paper with the punch and attack of aluminum, the HyDrive design produces serious tone that is ideal for bass players of all genres and styles.