The Colossus 18XB is intended for use as a high-output sub-bass driver either singly or in multi way systems. The unit features a 4 inch 'sandwich' inside and outside windings voice coil, immersed in a symmetric magnetic field and centralized by using two suspensions in a dual arrangement to maintain ultra linearity and stability at high excursions. The heavily ribbed straight-sided paper cone membrane is reinforced with high-strength composite fibres to resist deformation under extreme loads. The driver handles 1000 Watts (A.E.S.) continuous and can cope with peaks in excess of 4000 Watts. This is due to advanced thermal management in the form of a vented die-cast chassis and motor system using an internal heatsink coupled to a large vaned heatsink mounted on the rear of the unit. These measures effectively remove heat from the voice coil resulting in extremely low-power compression. The Colossus 18XB is designed for use in 100 to 250 Litre ported enclosures.
Please enquire about alternative impedances.
99 dB Sensitivity (1W/1m).
Great replacement driver for most bass reflex applications.
Vented chassis and motor design provides efficient thermal management and extremely low power compression.
High BL factor, 25.9 T/m.
Dual 'spaced' suspension system and advanced materials offers ultra-linearity, mechanical stability and superior acoustic performance at high levels of excursion.
Ribbed, fibre loaded, UK manufactured cone offers increased strength, durability and resistance to deformation under extreme loads.
Designed for optimum use in 100-250 Litre ported enclosure designs.
4-inch Inside/ outside windings copper voice coil.
A.E.S. power handling test. Pink noise bandpass filtered at 12 dB per octave with cutoff frequencies of 30 Hz and 300 Hz. Driver mounted in free air, test signal applied at rated power for two hours.
Please note that the frequency response measurements are supplied for comparison only and are not a measure of the low frequency performance which may be achieved in a fully optimised system.
Electro Acoustic Specifications
Nominal Chassis Diameter 18" / 457.2 mm
Impedance 4 /8 /16 Ω
Power Handling 1000 W (A.E.S.)
Peak Power (6dB Crest Factor) 4000 W (A.E.S.)
Usable Frequency Range (-6dB) 35 Hz - 1 kHz
Sensitivity (1W - 1m) Wideband 99 dB
Moving Mass (inc. Air Load) 173 grams
Minimum Impedance (Zmin) 6.5 Ω
Effective Piston Diameter 15.03" / 381.76 mm
Magnet Weight 120 oz
Magnetic Gap Depth 0.39" / 10 mm
Flux Density 1.2 Tesla
Coil Winding Height 0.90" / 23 mm
Voice Coil Diameter 4.0" / 101.6 mm
Speaker Type Sub Bass Driver
Speaker Series The Professional Series
Program Power 2000 W (A.E.S.)
Sensitivity (1W / 1m) Working band
Thiele Small Parameters (TSPs)
FS 33 Hz
Re 6.5 Ω
QMS 5.77
QES 0.358
QTS 0.337
Vas 236 Litres
Vd 0.803 Litres
CMS 0.13 mm/N
BL 25.9 T/m
MMS 173 grams
Xmax 7.5 mm
Sd 1131 cm2
Efficiency 2.3%
Le 1.99 mH
EBP 92.18 Hz
Materials of Construction
Coil Former Material Glass Fibre
Voice Coil Material Copper - Inside / Outside Windings
Magnet Material Ferrite
Chassis Material Die-cast Aluminium
Cone Material Straight Polycellulose Ribbed Cone
Surround / Edge Termination Polyvinyl Damped Multi Roll. Poly Cotton
Dust Dome Material Paper
Connectors Push-button Spring Terminals
Polarity Positive voltage at red terminal causes forward motion of cone
Mounting / Shipping Information
Overall Diameter 19.1" / 485 mm
Width Across Flats 18" / 457 mm
Flange Height 0.465" / 11.8 mm
Baffle Hole Diameter F/M 16.53" / 419.86 mm
Baffle Hole Diameter R/M 16.33" / 414.78 mm
Gasket Supplied Front & Rear
Outer Fixing Holes 8x ø 0.275" on 18.425" PCD / 8x ø 7 mm on 468 mm PCD
Inner Fixing Holes 8x ø 0.275" on 17.25" PCD / 8x ø 7 mm on 438.15 mm PCD
Depth 8.05" / 205 mm
Weight 31.29 lb / 14.2 Kg
Recommended Enclosure Volume 3.53 - 8.82 cu ft / 125 - 400 Litres
Shipping Weight 35.26 lb / 16 Kg
Packing Carton Dimensions (W) 512 (D) 512 (H) 244 mm
