Help KEF 104/2 what amp do I need to drive them?

The Cyrus 2 would need a PSX to really sing with KEFs.

In England a friend of mine ran Kef 103/4 with a Cyrus 2 / PSX and he could blow the walls off in a large living room.

But they're so rare it's probably a non-issue.

I think these speaker have low impedance at low frequencies, so they need a lot of current delivery ... that's probably where the yamaha falls over.

At $500 it's tricky to find good current delivery, but NAD and rotel would be the first names that come to my mind. If your receiver has preamp outputs just get a poweramp and you could get a better preamp later.

If you can find one then a used Audiolab 8000P power amp would work well and is a step up from NAD/rotel.

And if you ever find a used Mission Cyrus 2 with the PSX power supply then that would work a treat, but they are rare as hens teeth.

In fact here's one that looks good.

http://cls.audiogon.com/cgi-bin/cls.pl?ampstran&1124652835

Could you try it out? I have no personal experience with Krell, but unless someone here posts a response based directly on experience with the 300i driving 104/2s I would ask your friend if they mind you doing a quick home demo.