Instead of modding it into a new amp like this post does they likely just spliced the speaker wires right into the speakers. The upside is it was easy the downside is you can’t just plug and play after the fact.
Indeed! Nice thing is that two Symfonisk's give you great stereo sound on external speakers. And no soldering inside the Symfonisk, just some connectors to unplug and run the cable out of the bass reflex port, so easy to restore in original condition if you'd want to. So thanks to the magic of these tiny transistor digital amplifiers, in total you'll spend ± 500 euros and have better — and super convenient — sound than quite expensively priced systems.