18 Sound 15W700 – High-Sensitivity Ferrite 15-Inch Woofer with 99 dB Output and Excellent Transient Response
The 18 Sound 15W700 low frequency transducer meets the specific market demand for a loudspeaker which combines good linearity and efficiency with high power handling capabilities, containing a 75 mm aluminium voice coil. Although primarily intended for use in tuned reflex enclosures, the versatile characteristics of the 18 Sound 15W700 render it suitable for a wide variety of enclosure types, particularly as a subwoofer or as an LF driver in two or three-way systems. When used in a two-way system, 18 Sound recommends a 1.4-inch or 2-inch exit compression driver in order to obtain the best sound quality.
At 99 dB, the 18 Sound 15W700 delivers the highest sensitivity of any ferrite 15-inch driver in this comparison — 2 dB above the 15W930’s 98 dB and 2 dB above the 15W750’s 97 dB. The 38 Hz – 5000 Hz bandwidth is also the widest of the three, extending deeper into the bass and further into the upper mid-range simultaneously.
The deep-profile curvilinear paper cone has been made using a special high-strength wood pulp and designed to achieve the best possible linearity within its intended frequency range and to control bell-mode resonances around the cone circumference. The cone is carried by an unusually deep-profile, double half-roll suspension formed of a linen-like material which is more resistant to ageing and fatigue than the traditional cotton-based materials used in conventional surrounds — a distinct suspension geometry from the triple roll found on the 15W750.
18 Sound specifically credits improved heat dissipation via a unique basket design and excellent transient response as defining features of the 18 Sound 15W700, ideal for compact reflex subwoofers and multiway systems. Available in 4 and 8 Ω at 8.5 kg — the heaviest of the three ferrite 15-inch platforms covered, despite its shallower depth.
Design and Construction of the 18 Sound 15W700
The 75 mm aluminium voice coil employs the Interleaved Sandwich Voice Coil (ISV) technology, in which a high-strength fibreglass former carries windings on both the outer and inner surfaces to achieve a mass-balanced coil. This results in an extremely linear motor assembly with a reduced tendency for eccentric behaviour when driven hard.
The magnetic structure has been optimised using 18 Sound’s in-house FEA CAD resource that has maximised the flux density in the voice coil gap. The 18.4 Tm force factor driving 80 g of moving mass produces 99 dB sensitivity and the 0.30 Qts / 115 Hz EBP alignment — a moderately flexible Qts, sitting between the 15W930’s tight 0.22 and the 15W750’s more flexible 0.37.
Excellent heat dissipation has also been achieved by incorporating air channels between the basket and the magnetic top plate, alongside the unique basket design 18 Sound specifically credits for improved heat dissipation on this particular model.
The deep-profile curvilinear paper cone has been made using a special high-strength wood pulp and designed to achieve the best possible linearity within its intended frequency range and to control bell-mode resonances around the cone circumference. The unusually deep-profile double half-roll suspension, formed of a linen-like material, is more resistant to ageing and fatigue than traditional cotton-based materials.
Due to the increase in use of audio systems at outdoor events, the ability of the 18 Sound 15W700 to perform in adverse weather conditions or in areas of high humidity is a great advantage. This has been achieved using exclusive treatments which enable the cone and the magnetic plate to resist corrosion and render the cone water repellent at the same time.
At 8.5 kg, 387 mm overall diameter, 353 mm baffle cutout, 168 mm depth, and a substantial 19 mm flange, the 18 Sound 15W700 has the smallest overall diameter and shallowest depth of the three ferrite 15-inch drivers covered, despite carrying the most weight — a reflection of its denser, more compact motor and basket construction.
Performance and Applications for the 18 Sound 15W700
The 18 Sound 15W700 delivers 99 dB sensitivity across a 38 Hz – 5000 Hz bandwidth — the highest sensitivity and widest bandwidth of any ferrite 15-inch driver we’ve documented. 18 Sound’s published specification does not include a recommended enclosure volume, only a 45 Hz recommended tuning frequency — builders should consult the datasheet PDF directly or work from the published Vas (217 dm³) and Qts to derive an appropriate cabinet volume for their target alignment.
The 450 W AES / 700 W continuous program power handling, combined with the 6.5 mm Xmax, positions the 18 Sound 15W700 as ideal for compact reflex subwoofers and multiway systems — a driver optimised more for sensitivity and bandwidth than for the maximum displacement found on the 15W750’s 8.0 mm Xmax.
Excellent transient response is a feature 18 Sound specifically highlights, consistent with the driver’s genuinely wide bandwidth and the mass-balanced ISV coil’s inherent linearity advantage.
The comparison across all three ferrite 15-inch drivers now gives builders a clear three-way choice. The 15W930 delivers the tightest motor control (0.22 Qts) as the direct ferrite parallel to the flagship 15ND930, with SDR distortion reduction. The 15W750 delivers the most enclosure flexibility (0.37 Qts) and the widest impedance range (4/8/16 Ω). The 18 Sound 15W700 delivers the highest sensitivity (99 dB), the widest bandwidth (5000 Hz), and the shallowest depth (168 mm) — the efficiency and bandwidth specialist of the three.
Conclusion – 18 Sound 15W700 Woofer
The 18 Sound 15W700 combines good linearity and efficiency with high power handling capabilities, delivering the highest sensitivity (99 dB) and widest bandwidth (38–5000 Hz) of any ferrite 15-inch driver in 18 Sound’s range covered so far. The unique basket design’s improved heat dissipation and the driver’s excellent transient response make it particularly well suited to compact reflex subwoofers and multiway systems.
With no listed alternative model, the 18 Sound 15W700 stands as an actively maintained current platform. For applications where sensitivity, bandwidth, and shallow mounting depth matter more than maximum Xmax, this driver delivers a genuinely distinctive specification within 18 Sound’s ferrite 15-inch family.
VIEW MORE 18 Sound PRODUCTS HERE.
About 18 Sound
18 Sound products are proudly made in Reggio Emilia, Italy, combining advanced technology with Italian craftsmanship. Known for their high-performance professional audio components, 18 Sound is a trusted name in the global audio industry. Their state-of-the-art manufacturing and strict quality control ensure exceptional reliability and sound clarity. 18 Sound products are designed to meet the demands of speaker builders and audio professionals, 18 Sound offers premium products with outstanding value and performance worldwide.
