WS 20 E - 4 Ohm

Art. No. 1057

20 cm (8") HiFi woofer with polypropylene cone. Due to balanced frequency response curve suitable as low-midrange driver for large 4-way speaker systems. Due to the special basket design suitable as replacement driver for many HiFi speakers.

Technical Data

Rated power
80 W
Maximum power
120 W
Nominal impedance Z
4 Ohm
Frequency response
fu–7000 Hz
(fu: Lower cut-off frequency depending on cabinet)
Mean sound pressure level
88 dB (1 W/1 m)
Opening angle (-6 dB)
67°/4000 Hz
Excursion limit
+/−6 mm
Resonance frequency fs
47 Hz
Magnetic induction
0.85 T
Magnetic flux
400 µWb
Height of front pole-plate
5 mm
Voice coil diameter
30 mm
Height of winding
11 mm
Cutout diameter
186 mm
Net weight
1.3 kg
D.C. resistance Rdc
3.3 Ohm
Mechanical Q factor Qms
Electrical Q factor Qes
Total Q factor Qts
Equivalent volume Vas
39 l
Effective piston area Sd
240 cm²
Dynamically moved mass Mms
23 g
Force factor Bxl
4.5 T m
Inductance of the voice coil L
0.7 mH
5.2 x 0.8 mm (+)2.8 x 0.8 mm (−)
Frequency- and impedance response
Directivity pattern