
The X21 Subwoofer Cabinet was designed by Mark Seaton of Seaton Sound, a leading manufacturer of high-powered amplified and passive speakers. Mark Seaton designed the legendary AV123 MFW-15 Subwoofer and is one of the leading designers of powered subwoofers including the Submersive and F1 Submersive.
The X21 is available in different versions customised for the Beyma 21PW1400 FE, different 21" B&C Drivers (21IPAL, 21DS115, 21SW152 and 21SW115 - 1 to 8 ohms), and PRV 21SW 4000-NDY-4. The X21 page provides links for more information on those drivers, and possible suppliers in the US, including all other accessories, including terminals, wire, insulatio, etc, not provided with the kits.

WW Speaker Cabinets recommends some parametric EQ and an 16-20Hz, 2nd order or greater high pass filter, for optimal performance. Operation of the X21 at less than 1000W of amplification into the nominal driver load can function without a high pass filter while producing higher distortion. Intended operating range is 16-160Hz. Dual 6" flared ports are tuned to 19Hz with very low noise operation.
The X21 Subwoofer Cabinet dimensions are 24” (W) X 32” (H) X 32”(D). Unloaded X21 Cabinets weigh approximately 115 lbs; shipping weight is 175 lbs. X21 Subwoofer Cabinets are boxed and shipped via common carrier. Two people are required to remove the box from the truck unless lift gate delivery is requested. Shipping quotes do not include lift gate unless requested. RAW X21 cabinets are not finished and the grill is shipped without fabric. A pro-audio subwoofer cabinet for 21” drivers is also planned for release, featuring a smaller cabinet and tuning for commercial and concert settings.

All its products are manufactured in Mundelein, using advanced CNC equipment, lock-miter and miter construction where applicable. Rectangular woods speaker cabinets are fabricated using mill-veneered MDF panels or Russian Baltic Birch for professional audio speaker cabinets. Veneers typically used are maple, red oak, cherry and walnut. Other speaker geometries are fabricated using engineered fiber core material. All materials used by WW Speaker Cabinets comply with strict California CARB requirements. All finishes are water-based; no solvent based finishes are used, except under exceptional circumstances.
www.WW-Speakercabinets.com