You'd think that a tiny Ikea Symfonisk speaker wouldn't be able to power a large floor standing, horn-loanded Klipsch KG4 speaker but it works great. I now have a pair of bi-amped Klipsch speakers that sound amazing with the TruePlay room correction applied. All for $99 per speaker. I'd suggest looking for any highly efficient two way speakers with a 8" or smaller woofer for bi-amping wit your Symfonisk. The KG series is a great place to look and they are affordable.