ScanSpeak Illuminator 18WU/4741T-00 7″ Woofer, 4 ohm


Up for test is the ScanSpeak Illuminator 18WU/4741T-00 7″ Woofer, 4 ohm.  This particular scanspeak woofer has been one of the most impressive midwoofers I’ve tested to date.

340b5d50

Small Signal Testing:

  • Re = 3.2401 ohms
  • Fs = 40.2090 Hz
  • Zmax = 48.9959 ohms
  • Qes = 0.5031
  • Qms = 7.1050
  • Qts = 0.4699
  • Le = 0.2073 mH (at 1 kHz)
  • Diam = 137.1600 mm ( 5.4000 in )
  • Sd =14775.5910 mm^2( 22.9022 in^2)
  • Vas = 29.5769 L ( 1.0445 ft^3)
  • BL = 5.1700 N/A
  • Mms = 16.4284 g
  • Cms = 953.6699 uM/N
  • Kms = 1048.5808 N/M
  • Rms = 0.5842 R mechanical
  • Efficiency = 0.3591 %
  • Sensitivity= 87.5700 dB @1W/1m
  • Sensitivity= 91.4953 dB @2.83Vrms/1m

Scanspeak18wuImpTS

 

Large Signal LSI Klippel Testing:

Displacement Limits thresholds can be changed in Processing property page
X Bl @ Bl min=82% 11.6 mm Displacement limit due to force factor variation
X C @ C min=75% 9.1 mm Displacement limit due to compliance variation
X L @ Z max=10 % 12.6 mm Displacement limit due to inductance variation
X d @ d2=10% 37.1 mm Displacement limit due to IM distortion (Doppler)

This driver is flat out unreal. The symmetry is almost perfect for a stroke of it’s size, and the most limiting xmax is 9.2mm. Bl is 11.9mm.
The Cms curve is nearly perfectly symmetrical. Bl has a small shift.

img_BlX img_KmsX img_LX

Frequency Response and Harmonic Distortion Results:

 Scanspeak18wuFRHDSTDScanspeak18wuFRHD102

Leave a Reply

Your email address will not be published. Required fields are marked *