B&C 8CL51 8″ Professional Woofer LF Driver
The B&C 8CL51 is a professional 8-inch woofer LF driver engineered for compact high-efficiency loudspeaker systems requiring lightweight construction, controlled low-frequency performance, and strong thermal stability. Built around a neodymium inside slug motor structure and optimized moving assembly, the B&C 8CL51 delivers reliable output performance while significantly reducing overall driver weight, making it particularly suitable for portable professional audio systems.
Designed for compact two-way loudspeaker systems, stage monitors, portable PA systems, and professional low-frequency reinforcement applications, the B&C 8CL51 combines efficient thermal management with controlled excursion performance. Its lightweight motor architecture and compact loading characteristics allow designers to create smaller, lighter loudspeaker systems without compromising professional output capability.
Key Features
- 200 W nominal power handling
- 400 W continuous program power capacity
- 51 mm (2 inch) copper voice coil
- 94 dB sensitivity
- 70 Hz – 5000 Hz frequency response
- Neodymium inside slug magnet assembly
- Shorting copper cap for extended HF response
- Lightweight motor structure for portable applications
- WP waterproof front cone treatment
- Optimized for compact vented enclosure designs
Lightweight Neodymium Motor Structure
The B&C 8CL51 utilizes a neodymium inside slug motor assembly, providing a lightweight yet powerful magnetic structure designed for professional loudspeaker applications where reducing overall system mass is important. Neodymium motor technology allows the driver to maintain strong magnetic force while dramatically reducing weight compared to traditional ferrite alternatives.
The motor assembly incorporates a shorting copper cap, helping reduce inductance variation while improving upper-frequency behavior. Lower inductance modulation contributes to smoother response characteristics and improved crossover integration, especially in compact two-way designs.
With a measured 1.15 T flux density, the motor maintains effective control over cone movement while supporting stable output performance across the intended operating range. Combined with the lightweight magnetic structure, this contributes to both efficiency and reduced system weight.
Voice Coil Construction and Thermal Performance
At the center of the B&C 8CL51 is a 51 mm copper voice coil wound on a glass fibre former. This construction provides strong thermal stability while maintaining the mechanical strength required for continuous professional operation.
The driver supports 200 W nominal power handling and 400 W continuous program power, allowing reliable operation in demanding professional applications where sustained output capability is required. The combination of copper winding material and optimized motor geometry contributes to stable long-term thermal performance.
The relatively lightweight moving assembly, combined with optimized motor force, contributes to responsive transient behavior and controlled low-frequency reproduction.
Cone Geometry and Suspension Design
The B&C 8CL51 uses an exponential cone profile combined with a double roll surround geometry, supporting controlled cone movement while maintaining the excursion capability required for compact low-frequency applications.
A single spider suspension system provides mechanical stability and predictable cone control across the operating bandwidth. This design helps preserve efficiency while maintaining controlled movement under higher power conditions.
The cone assembly incorporates WP waterproof front-side treatment, improving resistance against humidity and environmental exposure in portable and installed sound reinforcement environments.
Compact Enclosure Integration
One of the major strengths of the B&C 8CL51 is its compact enclosure compatibility.
The manufacturer recommends a 17 dm³ enclosure volume with a 63 Hz tuning frequency, allowing designers to create compact vented systems while maintaining useful low-frequency extension and manageable cabinet dimensions. These loading characteristics make the driver particularly suitable for portable systems where enclosure size and weight must remain controlled.
Typical applications include:
- Compact two-way loudspeaker systems
- Portable PA cabinets
- Professional stage monitors
- Compact bass reflex enclosures
- Installed sound reinforcement systems
- Lightweight professional loudspeaker designs
Technical Specifications
Nominal Diameter: 200 mm (8 in)
Nominal Impedance: 8 Ω
Minimum Impedance: 6.3 Ω
Nominal Power Handling: 200 W
Continuous Program Power: 400 W
Sensitivity: 94 dB
Frequency Range: 70 Hz – 5000 Hz
Voice Coil Diameter: 51 mm (2 in)
Winding Material: Copper
Former Material: Glass Fibre
Winding Depth: 17 mm
Magnetic Gap Depth: 8 mm
Flux Density: 1.15 T
Magnet Material: Neodymium Inside Slug
Cone Shape: Exponential
Surround Shape: Double Roll
Spider Design: Single
Pole Design: Straight Pole
Cone Treatment: WP Waterproof Front Side
Recommended Enclosure: 17 dm³
Recommended Tuning: 63 Hz
Thiele-Small Parameters
Fs: 69 Hz
Re: 5.1 Ω
Qes: 0.44
Qms: 5.6
Qts: 0.41
Vas: 12.5 dm³
Sd: 220 cm²
η₀: 0.9 %
Xmax: 6.5 mm
Xvar: 6 mm
Mms: 29 g
BL Factor: 12 Tm
Le: 0.5 mH
EBP: 157 Hz
Mounting Information
Overall Diameter: 209 mm
Bolt Circle Diameter: 199 mm
Baffle Cutout Diameter: 186 mm
Depth: 96 mm
Flange and Gasket Thickness: 9 mm
Air Volume Occupied by Driver: 1.1 dm³
Net Weight: 1.25 kg
Shipping Weight: 1.7 kg
Shipping Box: 255 × 255 × 150 mm
Recone Kit: RCK008CL518
Applications
The B&C 8CL51 is engineered for professional low-frequency applications where reduced weight, compact loading, and reliable output performance are priorities. Its lightweight neodymium motor structure, compact enclosure compatibility, and efficient operating characteristics make it suitable for portable PA systems, stage monitoring applications, compact loudspeaker systems, and professional installed audio environments.
For system designers requiring a lightweight professional woofer optimized for compact enclosure designs and reduced system mass, the B&C 8CL51 provides an effective combination of efficiency, portability, and professional-grade performance.
VIEW MORE B&C PRODUCTS HERE.
About B&C Speakers S.r.L.
B&C Speakers products are built in Bagno a Ripoli (Florence), Italy., ensuring high quality products to suite your speaker building requirements. Their 10,500 square meter facility incorporates highly sophisticated automation and quality control. Over the years they become one of the world leaders in the Professional Audio market, a brand recognized everywhere as a premium product that offers excellent value to the consumer.
