The question might be are you going to be replacing the Kappa 7's for the PSB Synchrony or keep the Kappa's with this amp. Because it looks like the Kappa 7's may have some ohm dips at certain frequencies that go down to 2 ohms or so. Using a bridged amp for that is not recommended in most cases.
If you're interested in the A21, they do go on sale. I bought mine from a dealer who shipped it to me for under 2K. And there might be deals on Audiogon used as well. The W4S I'm not as familiar with, but they have lots of power too. You just need a dealer willing to deal.
If you're interested in the A21, they do go on sale. I bought mine from a dealer who shipped it to me for under 2K. And there might be deals on Audiogon used as well. The W4S I'm not as familiar with, but they have lots of power too. You just need a dealer willing to deal.