Compact active sub-woofer (Tiffield NN12)

Eltax A-6.2
Can act as an amplifier (hence ‘active’) for a pair of speakers as well as for the sub-woofer. The possible connections are shown in the picture of the back.
Dimensions cm (approx.) : 27 D x 25 W x 28 H
With manual.
There’s a slight hum, more noticeable in our set-up as the unit is tight into a corner.
It now seems to need more input than our pre-amp can provide. And, as our music tastes have changed, we no longer need the extra ‘thump’ ! So it’s surplus to requirements.