Do-it-yourselfers, here’s your chance to create your personal sub that perfectly fits into your car!
From the technical point of view the two drivers K 10W and K12W are absolutely identical with the subwoofers that are installed in the K series enclosure subs.

Just have a look at the Thiele/Small parameters and you will easily notice that those are designed for compact vented cabinets yet leaving plenty of “headroom” for designing your own preferred sound characteristic. If you prefer to play it safe, just choose the same net volume and port tuning frequency like our enclosure subs K 10E and K 12E for outstanding bass performance.

So what are you waiting for? Start your “tailor-made subwoofer project” right now!



  • Extremely stiff, hand-scooped paper cone
  • Double ventilated voice coil for minimum compression effects and high power handling
  • Long-excursion rubber surround for highest mechanical rating
  • Very long linear excursion
  • 2 x 2 Ohms dual voice coil for flexible system configuration
  • Solid push terminals
  • Powerful magnet system for compact vented enclosures
  • Rugged magnet cover with HELIX lettering for perfect magnet protection
  • Grille and gasket included in delivery
Power RMS / max. P300 / 600 Watts
Impedance Z2 x 2 Ω
DC resistance Re2 x 1.6 Ω
Resonance frequency Fs36 Hz
Mechanical Q factor Qms4.50
Electrical Q factor Qes0.43
Total Q factorQts0.39
ComplianceCms218 μm/N
Equivalent air volumeVas34 L
Force factor B*I12.3 Tm
Efficiency 1 W / 1 mSPL88.0 dB
Cone area Sd333 cm²
Moving mass Mms91 g
Cone material Hand-scooped paper cone
Mechanical resistance Rms4.56 kg/s
Voice coil diameterø50.8 mm
Voice coil winding height 24 mm
Max. linear excursion Xmax+/- 8.0 mm
Outer diameterø262 mm / 10.31″
Installation diameterø232 mm / 9.13″
Installation depth 126 mm / 4.96″
Recommended enclosure volumes 
Sealed box 
Net volume 12 L
Lower limiting frequency (-3dB) 53 Hz
Vented box 
Net volume 19 L
Port diameterø70 mm / 2.76″
Port area 38 cm²
Port length 22 cm / 8.66″
Port tuning frequencyFb43 Hz
Lower limiting frequency (-3dB) 43 Hz
Delivery contents

1 x Subwoofer HELIX K 10W
1x Grille
1 x Gasket
1 x Data sheet