Elegantly designed mid-woofer trimmed for maximum sound quality. 

The extremely rigid cone consists of a novel basalt-fiber-paper compound – the perfect combination to guarantee clear and straight sound even at high volume levels. Beside a powerful bass reproduction and peerlessly neutral mids, the S 4B impresses with exceptionally low distortion.

A dream team is a combination with the S 1T tweeter that ideally complements the frequency range. Together with an Audiotec Fischer power amplifier, the S loudspeakers strike up to top form and provide the perfect basis for absolute top sound systems!

4” / 100 mm mid-woofer with novel basalt-fiber-paper compound cone – a perfect combination of lowest weight, high stiffness, and inner damping

Specially shaped rubber surround for larger effective cone area and increased maximum excursion

Individual HELIX basket with additional ventilation holes for better voice coil cooling and high power handling

Rugged rubber magnet boot with HELIX-logo

Gold-plated terminals

Power RMS / max. P 70 / 140 Watts

Impedance Z 4 Ω

DC resistance Re 3.4 Ω

Frequency response 75 Hz - 6,000 Hz

Resonance frequency Fs 120 Hz

Mechanical Q factor Qms 4.24

Electrical Q factor Qes 1.11

Total Q factor Qts 0.88

Compliance Cms 232 μm/N

Equivalent air volume Vas 1.2 L

Force factor B*I 4.1 Tm

Efficiency 1 W / 1 m SPL 89 dB

Cone area Sd 61 cm²

Moving mass Mms 5.9 g

Cone material Basalt-fiber-paper compound

Mechanical resistance Rms 1.19 kg/s

Voice coil diameter ø 25 mm

Voice coil winding height 12 mm 

Max. linear excursion Xmax +/- 3 mm

Outer diameter ø 102 mm / 4.01"

Installation diameter ø 92.3 mm / 3.63"

Installation depth 46.5 mm / 1.83"

   

Recommended enclosure volumes  

Sealed box  

Net volume 3 L

Lower limiting frequency (-3dB) 100 Hz

Delivery contents

2 x Mid-woofer HELIX S 4B

1 x Mounting material

1 x Datasheet

1 x Mounting pattern

We take great care packaging every item to ensure safe shipment to you. Our postage and courier charges not only cover the shipping cost, but also the time to pack your order, plus packaging supplies etc.  Please note - some items may incur extra shipping charges that have to be sent by courier and are too large/expensive to be sent by Royal Mail (for example headlamps, head units, speakers, lowering springs etc) to the following postcode areas, Channel Islands, BT, most IV, HS, KA-27-28, Any KW, AB30-56, FK17-99, G83, KW1-14, PA21-40, PH18-26, PH30-41, PH49-50, all ZE, IM, and any other non-mainland postcodes.