15 in full range drivers

Some things need more help than they’re worth, but you’re really the only one that can decide whether to keep working on them or get rid of them. How optimized is the rest of your system, and how much experimenting with placement have you done?

The fact that you used the word "suffering" is a pretty strong hint....so is the fact that your wife doesn’t like them.

your experiences with low-powered amps are very common. you can only use SET for vocals and other music is literally disaster to listen to.

Great responses, thank you.  The Tannoy's are what I tried to build myself.  Definitely an option with either the Super Gold 10 or 12's.  I am afraid to go listen to them as it may end up being an expensive day.  I have the Western Electric 300B sets and just last night hooked up my Parasound A21 with a Parasound pre amp from a Bluesound Node streaming HD music. The Parasound was driving some Sonus Fabers in another room.  The Solid state is overall a better sound for most.  But for certain music, the 300B's are magical, however in general are to "smoothed out" as my wife says.   

Room is 15 x 15 ft, and10 ft ceiling, area rug, no room treatment with back wall having large walk through opening.  When we sit off center it is less fatiguing, but also loses its sparkle.  Most likely will keep the Parasound driving them and just connect the 300B when appropriate.  Most likely the tubes will just sit there and look cool. LOL.

Go with new speakers. Full range drivers suck at reproducing multiple frequencies at the same time.  That’s what’s causing the fatigue. Of course they sound beautiful with voices,  but add some drums, a guitar or two and it’s a total mess.  That dog don’t hunt. A Heritage speaker would be a much better choice. 

To suggest that a full range driver coupled with an SET amp is limited to vocals or a small segment of music is just not true for many of us. In fact, quite the opposite.  I have two systems that could be not more different.  One has Tekton DI's coupled to a pair of HSU 15 inch subs powered by Marantz Ruby electronics.  Very little that system can't handle.  My second system has a pair of Omega monitors driven by an Erhard Ray 6L6 SE integrated.  I can listen to a large part of my music collection on this system all day long.  No fatigue.  I dare say I might listen to this system more than my other--but I love them both.  

You might find this site interesting--check out glowinthedarkaudio.com especially if you are into DIY full range drivers.  

@zagorskia  what 15" driver are you using?