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.
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.