Celto Pro · SUBIUM Series
SU221
SKU: SU221
High-performance professional vented subwoofer featuring dual 21-inch transducers and 3600 W RMS power handling for deep low-frequency reproduction.
- Max SPL
- 137 dB RMS / 143 dB Peak
- Frequency Response
- 28 Hz – 1.5 kHz
- Driver Configuration
- 21"
- Dispersion
- Omni in usable range
- Weight
- 104 kg (229.3 lb)
2-year distributor warranty · Original product · Engineering support
Overview
The Celto Acoustique SU221 is a high-performance dual 21-inch vented subwoofer system engineered to deliver extreme low-frequency extension and high sound pressure levels in demanding professional audio installations and touring applications. The system is equipped with two custom 21-inch CELTO 21SW2000-8 transducers, featuring die-cast aluminum chassis and 4.
5-inch (115 mm) long-throw voice coils. Operating at a nominal impedance of 4 Ohms, the SU221 handles 3600 W RMS (14400 W peak) of power. With an average sensitivity of 102 dB (1W/1m), it achieves a calculated maximum SPL of 137 dB continuous (143 dB peak), delivering deep and impactful bass down to 28 Hz (up to 1500 Hz). The enclosure is constructed from marine-grade Baltic birch plywood, heavily braced with tongue-and-groove joints to eliminate resonance. The exterior features a highly durable touring-grade rubberized PolyUrea coating and acoustic PU foam behind the front steel grille. For versatile setup options, the cabinet includes two M20 threaded pole-mount sockets and genuine Neutrik Speakon NL4MP connectors.
143 dB
MAXIMUM PEAK SPL
28 Hz – 1.5 kHz · Frequency Response
Technical Specifications
SU221 · SKU SU221
| ACOUSTIC PERFORMANCE | |
|---|---|
| Speaker type | Vented Subwoofer |
| Power Handling (AES standard) | 3600 W RMS / 14400 W peak |
| Nominal impedance | 4 Ω |
| Average sensitivity | 102 dB / 1 W / 1 m |
| Maximum SPL (calculated) | 137 dB RMS / 143 dB Peak |
| Frequency response (-6 dB no preset) | 28~1500 Hz |
| Nominal directivity (-6 dB) | Omni in usable range |
| Crossover | No, active mode only |
| DRIVERS | |
| LF | 2x 21" CELTO 21SW2000-8 |
| Woofer Chassis | Die Cast Aluminium |
| Woofer Voice coil | 4.5" / 115 mm long throw |
| CABINET & MOUNTING | |
| Cabinet | Marine grade Baltic Birch PlywoodHeavily braced with Tongue & Groove |
| Cabinet finish | Touring Grade Rubberized PolyUrea Black coatingAcoustic PU foam behind Front grill |
| Flying hardware | No |
| Mounting hardware | 2pcs M20 thread socket |
| CONNECTIVITY | |
| Connectivity | Genuine NEUTRIK 2pcs Speakon NL4MP |
| PHYSICAL | |
| Speaker size (HxWxD) | 588 × 1226 × 805 mm (23.1 × 48.3 × 31.7 in) |
| Speaker Weight | 104 kg (229.3 lb) |
| Shipping information | 117 kg710 x 1380 x 915 |
| Accessories | CSW221-SBAG (padded cover bag)CPC-70 (pole bar with crank)SUBWHKIT100C (castor wheel kit) |
SU221 · 2-year distributor warranty · Original product · Engineering support
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Frequently Asked Questions
What is the price of SU221?
Pricing depends on your project configuration. Contact our engineering team to determine the most suitable setup and receive a current quote.
What does the distributor warranty cover?
Every system we install is our direct responsibility for two years against manufacturing defects, with scheduled measurement, calibration and maintenance support.
How is product originality guaranteed?
We import all required parts and products directly from the manufacturer's factory, preserving the authenticity of the system.
How does the design & quote process work?
Let us build the acoustic infrastructure of your project to engineering standards with needs analysis, detailed venue exploration, and accurate technical guidance.
2-year distributor warranty · Original product · Engineering support