
N.C. Madsensvej 1 · 6920 Videbæk · Denmark · Phone: +45 6040 5200 · www.scan-speak.dk
MIDWOOFER 18W/8542-00
The Symmetric Drive (SD) concept with copper in the magnet system was invented by
Scan-Speak. High-quality magnet system design has thus been a key feature of Scan-
Speak design since the companys inception. The Classic woofers are highly praised,
and are used in some of the worlds most exceptional high-end Loudspeakers. Some
feature Kevlar cones, others have the innovative Carbon fibre paper cones.
KEY FEATURES:
· Patented Symmetrical Drive Motor Design
· Air Dried Paper/Carbon Fibre Cone
· 42mm Voice Coil
· Low-Loss linear suspension
· Low Damping Coated Foam Surround
Notes:
IEC specs. refer to IEC 60268-5 third edition.
All Scan-Speak products are RoHS compliant.
Data are subject to change without notice.
Datasheet updated: February 22, 2011.
T-S Parameters
Resonance frequency [fs] 30 Hz
Mechanical Q factor [Qms] 1.70
Electrical Q factor [Qes] 0.26
Total Q factor [Qts] 0.23
Force factor [Bl] 7.8 Tm
Mechanical resistance [Rms] 1.66 kg/s
Moving mass [Mms] 15 g
Suspension compliance [Cms] 1.88 mm/N
Effective diaph. diameter [D] 131 mm
Effective piston area [Sd] 135 cm²
Equivalent volume [Vas] 47.9 l
Sensitivity (2.83V/1m) 89 dB
Ratio Bl/√Re 3.33 N/√W
Ratio fs/Qts 133 Hz
Electrical Data
Nominal impedance [Zn] 8 Ω
Minimum impedance [Zmin] 6.6 Ω
Maximum impedance [Zo] 41.5 Ω
DC resistance [Re] 5.5 Ω
Voice coil inductance [Le] 0.2 mH
Power Handling
100h RMS noise test (IEC 17.1) 70 W
Long-term max power (IEC 17.3) - W
Voice Coil and Magnet Data
Voice coil diameter 42 mm
Voice coil height 19 mm
Voice coil layers 2
Height of gap 6 mm
Linear excursion ± 6.5 mm
Max mech. excursion ± 10 mm
Unit weight 2.1 kg