Scan Speak Illuminator 18WU/4741T-00 7" Woofer 4 Ohms

Scan-Speak Illuminator 7" Paper Cone Woofer 18WU/4741T-00

• Under hung voice coil
• Neodymium magnet
• Exceptionally long linear excursion
• paper cone

The Illuminator woofers are based on compact under-hung motor systems with large neodymium ring magnets. The patent pending motor offers a very long linear excursion together with a very high force factor. The top plate is shaped to “guide” the backside airflow around the motor and with the very open cast aluminum chassis design the driver is virtually free from compression.

Nominal Impedance	Zn	4	ohm
DC Resistance	Re	3.2	ohm
Voice Coil Inductance	Le	0.5	mH
TS Parameters
Resonance Frequency	fs	30	Hz
Mechanical Q factor	QMS	3.56
Electrical Q factor	QES	0.32
Total Q factor	Qts	0.29
Force Factor	Bl	6	Tm
Mechanical Resistance	Rms	1	Kg/s
Moving Mass	Mms	18.9	g
Suspension Compliance	Cms	1.49	mm/N
Effective Piston Area	sd	154	cm^2
Equivalent Volume	Vas	49.9	ltrs
Sensitivity	2.83V/1m	87.2	dB

Power Handling
100h RMS noise test	IEC	80	W
Long Term Max Power	IEC 18.3	150	W
Voice Coil and Magnet Parameters
Voice Coil Diameter		42	mm
Voice Coil Height		8	mm
Voice Coil Layers		4
Height of the Gap		20	mm
Linear Excursion +/-		6	mm
Max mech. excursion +/-		16	mm

Suggested alignment:
Sealed box of 0.25 cubic feet for an F3 of 80Hz
Vented box of 0.5 cubic feet with a 2" diameter vent by 8" long for an F3 of 55Hz
Vented box of 0.75 cubic feet with a 2" diameter vent by 7" long for an F3 of 50Hz