Silverline Sonata III vs. Coincident Total Eclipse

A cirtain would look hideous. Invest in some nice "soft" artwork, tapestry's or similar and you will get a better look and probably better results.

good point about the curtain...its not really needed except that right now the room is super "live" and i thought i might need it for acoustics...no other reason and experimentation will determine the best course...

I've never heard any Silverline speakers, but I've heard a bunch of Coincidents, and the current models are uniformly excellent.

A friend has Total Eclipses running on VAC 70 watters in a bigger room than yours. I have the Total Victories, and they're playing right now on 6 watt PX-25 amps, with amazing dynamics, volume and soul. 6 watts probably wouldn't be enough on the TE's, but 25 or 30 ought to do them just fine.

I've also heard Super Eclipse III's running on a Manley Neo-Classic 300B amp, and again there was no lack of volume. It was in a room that was higher and wider than yours but not as long - I'd estimate 18x25x10. This setup really impressed me, so don't write off the SEIII just because it's smaller.

Haven't compared them but,
Coincident speakers are amazingly efficient with loads of bass. They will fill that room with 3 watts!

Why curtain it off? It won't help/hurt acoustics unless your curtain is about a foot thick and still, the bass will dissipate.