Proel S15P S-Series Passive Subwoofer - 15"PROEL introduces the S Series, a new range of compact and powerful sub woofers designed to complement PROEL full range speakers. The variety of size, power and SPL offered by the three passive S models provides, at an unbeatable price point, the perfect low extension solution for any speaker model available in the PROEL range. All the S models feature high excursion woofers in a Hybrid Band Pass configuration (HBP). This innovative design provides a