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USER MANUAL
SW218P
passive subwoofer
KEY FEATURES
• Very High Output
• Manifolded Transmission Line configuration for very fast transient response
• Compact size for a very good output-toweight ratio
INTRODUCTION
The SW218P subwoofer is designed to deliver high quality low frequency reproduction where very high output is a key requirement, together with
well defined deep bass response and fast transient response. Its compact size and light weight make it suitable for several different uses, ranging
from touring applications to fixed installations and high-level dance clubs.
The SW218P is a very high quality powered subwoofer system featuring some of the most advanced
technologies for low frequency reproduction. Its unique and innovative design is based on a configuration
that can be defined as Manifolded Transmission Line.
It uses manifolding of the front side of the cones to maximize the mutual coupling between the
two drivers, while loading the back of the cone with a large-size transmission line that has the
function to create a transmission path from the back of the transducers to the front. This innovative
configuration does not use any large resonant cavity to load the speaker in order to get the lower
octave and this reduces significantly pressure decay time inside the enclosure, with large advantages
in terms of definition both at the lowest end and the upper bass. At the same time, it doesn’t use very
long transmission line paths as well. Its working principle is an hybrid combination between a short
transmission line and an overdamped reflex load. Moreover, the maximization of the mutual coupling
between the drivers increase the fastness of the transient response while maximizing the overall energy
efficiency as well.
The SW218P subwoofer system is equipped with two high power 18” (460mm) transducers capable of long excursion (up to 30mm peak-to-
peak), controlled by high stiffness Double Silicon Spider as centering suspension and by heavy duty surround. The motor structure features high
strength (BL²/Re) with optimized symmetry and excursion controlled by Inner Flux Demodulating Ring. The robust copper 100mm (4”) voice coil is
wounded in two different layers both outside and inside the coil support, then doubling the coil surface exposed to air cooling and consequently
improving the long term thermal capacity of the loudspeaker. Cones are made of very high-stiffness glass fiber reinforced paper, featuring also
invisible water repellent treatment.
TECHNICAL SPECIFICATION
Acoustical
Connectors
System type
Manifolded Transmission Line
Connector Type
Neutrik® Speakon® NL4 x 2
Transducer
Two 18” (460 mm), 4” (100 mm) VC,
High stiffness, water repellent, glass fibre
reinforced cone
Flux Demodulating Ring VC
Double Centering Spider Suspension
Input Wiring
LF1 = Pin 1+/1-; LF2 = Pin 2+/2-
Mechanical
Width
1215 mm (47.87”)
Height
590 mm (23.24”)
Depth
950 mm (37.43”)
Frequency response (±3 dB)
30 Hz – 92 Hz (Processed)
Depth Including Wheels
1050 mm (41.37”)
Frequency response (±10 dB)
27 Hz – 300 Hz (Unprocessed)
Construction
15 mm, reinforced Phenolic Birch
Sensitivity (1.41V @ 1m, 2Pi)
101 dB (averaged from 40 to 100 Hz)
Paint
High resistance, water based paint
Maximum Peak SPL @ 1m
141 dB
Wheels
4 heavy-load 100 mm ø
Electrical
Transport
10 handles
Nominal Impedance
4 Ω + 4 Ω
Net Weight
98 Kg (216 lbs.)
Minimum Impedance
3.2 Ω + 3.2 Ω @ 36 Hz
Power Handling Continuous*
800 W + 800 W
Power Handling Program
1200 W + 1200 W
Power Handling Peak
2400 W + 2400 W
Power Compression
@ -10 dB Power (180 W + 180 W) = 0.8 dB
@ -3 dB Power (900 W + 900 W) = 1.5 dB
@ 0 dB Power (1800 W + 1800 W) = 2.7 dB
* AES Pink Noise Power
revision 2019-05-15