Active bass-reflex subwoofer with 200 mm woofer driver. The Betasub 20A is the smallest model in the Betasub series and is driven by a 140 watt high-performance power amplifier. This subwoofer covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz.

Betasub 20 A

Beta Sub

Active bass-reflex subwoofer with 200 mm woofer driver. The Betasub 20A is the smallest model in the Betasub series and is driven by a 140 watt high-performance power amplifier. This subwoofer covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz.

Active bass-reflex subwoofer with 200 mm woofer driver


Active bass-reflex subwoofer with 200 mm woofer driver. The Betasub 20A is the smallest model in the Betasub series and is driven by a 140 watt high-performance power amplifier. This subwoofer covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz.

Numerous tests underline the excellent performance


This, the smallest but still powerful Betasub model, is powered by a 140 watt high-performance power amplifier and covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz.

Active bass-reflex subwoofer with 200 mm woofer driver. The Betasub 20A is the smallest model in the Betasub series and is driven by a 140 watt high-performance power amplifier. This subwoofer covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz. This, the smallest but still powerful Betasub model, is powered by a 140 watt high-performance power amplifier and covers a low-bass bandwidth that ranges from 200 to 25 Hz – which is infinitely adjustable between 200 and 50 Hz. The downfire case design enables the subwoofer to deliver a bass that in relation to its external dimensions is very deep and powerful. The reason: the cone surface area has been fitted at a very small and precisely defined distance from the floor in the solid and low-resonance case. The driver is supported by the Airflex bass-reflex port that has been secured to the front of this bass powerhouse with five screws. The Betasub 20A is the ideal bass partner for a loudspeaker from Magnat´s Shadow series.

Flow-optimised bass reflex port

Downward-firing subwoofer chassis for an enhanced bass range

Filter circuit for optimisation of the frequency response in subwoofers

Active control circuit for limiting cone excursion