Sound Barrier SWX221 — High-Output Dual 21″ Passive Subwoofer
SWX221 Overview
The Sound Barrier SWX221 is a dual 21-inch passive subwoofer built for large-scale professional sound reinforcement where maximum low-frequency output and system flexibility are non-negotiable. At its core are two high-excursion 21-inch drivers equipped with 6-inch voice coils, engineered for extreme power handling and long-term thermal stability. The cabinet delivers a frequency response of 26 Hz to 200 Hz (-3 dB) and a peak SPL of 146 dB, making it a viable solution for touring systems, festivals, nightclubs, outdoor events, and high-capacity permanent installations. System engineers, touring companies, and integrators deploying large-format PA or line-array systems will find the SWX221 a capable and flexible foundation for demanding subwoofer arrays.
The SWX221’s passive architecture integrates directly into existing amplification and DSP-based processing chains, supporting ground-stacked arrays, line-array deployments, and mobile touring rigs with equal effectiveness.
Key Features
- Dual 21″ High-Excursion Drivers — Two purpose-built low-frequency drivers move large air volumes with precision, delivering deep, controlled bass at extreme output levels
- 6-Inch Voice Coils — Oversized voice coils on each driver provide superior power handling, thermal stability, and long-term reliability under sustained high-output operation
- Independent Dual 4-Ohm Wiring — Each driver is wired separately rather than combined internally, allowing each 21-inch driver to be driven by its own dedicated amplifier channel for optimized power delivery and control
- NL4 (speakON-Type) Connectivity — Driver 1 is assigned to pins 1+/1- and Driver 2 to pins 2+/2-, enabling clean, secure, touring-grade signal routing without additional adapters
- 146 dB Peak SPL — Capable of supporting the most demanding audio environments, from large outdoor festivals to high-capacity nightclubs and arena-scale touring systems
- Frequency Response: 26 Hz to 200 Hz (-3 dB) — Extended low-frequency reach with sensitivity rated at 104 dB / 1W / 1M
- Tour-Grade Birch Plywood Enclosure — Heavy-duty construction with a durable road-ready coating and reinforced steel grille for driver protection and unrestricted airflow
- Passive Architecture — Designed for use with professional external amplification and system processing, integrating seamlessly into advanced DSP-driven PA systems
Connectivity & I/O
- NL4 (speakON-type) connector — Driver 1 on pins 1+/1-, Driver 2 on pins 2+/2-
Technical Specifications
| Driver Configuration | Dual 21″ high-excursion low-frequency drivers |
| Voice Coil Diameter | 6 inches (per driver) |
| Impedance | Dual 4 ohms (independent, one per driver) |
| Wiring | Independent — Driver 1: pins 1+/1-, Driver 2: pins 2+/2- (NL4) |
| Frequency Response | 26 Hz – 200 Hz (-3 dB) |
| Sensitivity | 104 dB / 1W / 1M |
| Maximum SPL | 146 dB peak |
| Enclosure Material | Tour-grade birch plywood |
| Grille | Reinforced steel |
| Type | Passive |
Reviews
There are no reviews yet.