Danley TH121-I-B Tapped Horn Subwoofer High-Output 21" | Install Version | BlackThe Danley TH121 is a passive high output subwoofer built around Danleys patented tapped horn design. By using both sides of the 21 inch neodymium driver within the folded horn path, the enclosure is engineered to deliver strong low frequency efficiency with reduced cone excursion at elevated drive levels. For production companies, venues, and integrators that need substantial bass from a single enclosure, the TH121 is designed for serious