20 cm (8") High-End woofer with black glass fibre cone, solid aluminium die-cast basket and elastic rubber surround.  Designed for multi-purpose applications due to 2 x 4 ohms double  voice-coil, with excellent properties as 8 ohms drivers in series  configuration. The long stroke voice-coil in conjunction with the  extended rear pole plate, the vented damper, the vented magnet and the capton voice-coil carrier guarantees long strokes and highest power handling.
Possible connections:
(1) one voice coil not connected
(2) both voice coils in series
(3) both voice coils in parallel
 
| Technical Data: | 
|---|
                                                   | Rated power | 120 W | 
                        | Maximum power | 180 W | 
                                 | Nominal impedance Z | (1) 4 Ohm (2) 8 Ohm
 (3) 2 Ohm
 | 
                                  | Frequency response | fu–8000 Hz | 
                            | (fu: Lower cut-off frequency depending on cabinet) | . | 
                        | Mean sound pressure level | (1) 85 dB (1 W/1 m) (2) 88 dB (1 W/1 m)
 (3) 88 dB (1 W/1 m)
 | 
                             | Opening angle (-6 dB) | 46°/4000 Hz | 
                             | Excursion limit | +/−10 mm | 
                        | Resonance frequency fs | (1) 34 Hz (2) 30 Hz
 (3) 35 Hz
 | 
                        | Magnetic induction | 1,3 T | 
                        | Magnetic flux | 930 µWb | 
                        | Height of front pole-plate | 6 mm | 
                        | Voice coil diameter | 38 mm | 
                        | Height of winding | 18 mm | 
                        | Cutout diameter | 190 mm | 
                        | Net weight | 2,5 kg | 
                        | D.C. resistance Rdc | (1) 2,9 Ohm (2) 5,8 Ohm
 (3) 1,4 Ohm
 | 
                        | Mechanical Q factor Qms | (1) 4,51 (2) 4,12
 (3) 4,33
 | 
                        | Electrical Q factor Qes | (1) 0,93 (2) 0,37
 (3) 0,44
 | 
                        | Total Q factor Qts | (1) 0,77 (2) 0,34
 (3) 0,39
 | 
                        | Equivalent volume Vas | (1) 62 l (2) 68 l
 (3) 57 l
 | 
                        | Effective piston area Sd | 214 cm² | 
                        | Dynamically moved mass Mms | 25 g | 
                        | Force factor Bxl | (1) 4,6 Tm (2) 9,2 Tm
 (3) 4,6 Tm
 | 
                        | Inductance of the voice coil L | (1) 0,4 mH (2) 1,1 mH
 (3) 0,3 mH
 |