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The RS Speakers W 140.38 Fibonacci Bass-mid woofer is a premium 5.5-inch driver that combines innovative Italian engineering with patented technologies to deliver exceptional sound quality. Featuring a unique custom paper pulp cone with a Fibonacci-inspired design, this woofer is crafted for audiophiles seeking clarity, low distortion, and a pure listening experience. Its advanced construction boasts a dual-asymmetric rubber surround, progressive Conex spider, and a high-performance ferrite magnet circuit, making it an excellent choice for high-end home audio systems and demanding DIY speaker projects.
RS Speakers W 140.38 Fibonacci 5.5” Woofer 8 Ohm
The heart of the W 140.38 Fibonacci is its meticulously engineered diaphragm, which uses a custom para-elliptical profile and a laser-etched Fibonacci sequence pattern. This innovative design, inspired by the Golden Ratio, minimizes unwanted resonance modes and increases cone rigidity exactly where it is needed most. The result is a remarkably clean and natural sound character, making this woofer a standout in the speakers category for both home audio enthusiasts and professional builders.
Performance is further enhanced by the woofer’s double surface damping treatment, which creates a “sandwich” structure with acrylic and damping layers. This approach strikes a balance between stiffness and internal damping, effectively controlling cone break-up and unwanted coloration. The specially designed NBR butyl rubber surround utilizes Double Asymmetric Rolls technology, ensuring symmetrical and linear excursion even at high output levels. Combined with a progressive Conex spider, the mechanical design supports extended excursion while maintaining precise control.
At the core of the motor assembly, the 1.5-inch voice coil is wound on a fiberglass former, providing excellent mechanical stability and heat resistance during demanding sessions. The ferrite magnet circuit incorporates an aluminum demodulating ring, significantly reducing coil inductance and harmonic distortion. Ventilation for both the magnet and voice coil helps to minimize power compression, ensuring consistent performance even in high-power applications. With a sensitivity of 86.2 dB at 1W/1m and a power handling of 120W AES (240W program), the W 140.38 Fibonacci is ready to excel in a wide range of woofers and midbass duties.
Designed for flexibility, this woofer is ideal for use in custom loudspeaker systems, high-fidelity home audio setups, or ambitious DIY speaker kit projects. Its thoughtful mounting features, including a free compression basket design with thin spokes to eliminate rear reflections, and the inclusion of a sealing gasket, fixing screws, and griff-nuts make installation straightforward. Whether you are upgrading an existing system or building from scratch, the RS Speakers W 140.38 Fibonacci delivers uncompromising performance and sonic purity.
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Speakers
Amplifiers
DAC converters
DSP modules
Turntables
Streamers
Woofers
Tweeters
Exciters
Bass shakers
Plate amplifiers
Amplifier modules
Single board computers
Assembled crossovers
Printed Circuit Boards (PCB)
Capacitors
Resistors
Coils
Circuit Breakers
Crossover tools
Screw terminals
Acoustic measurements
Electric measurements
Sound level meters
DIY amplifier kits
DIY component packs
DIY speaker kit
DIY subwoofer kits
DIY bluetooth speaker
DIY electronics kits
Binding posts
Cabinet Hardware
Cables
Connectors
Speaker cabinets
Electromechanics
Power supplies
Speaker repair
Workshop & tools
Amplifier accessories
Stands & mounts
Gift voucher
Books
New products
