How to fix my detailed, accurate but BRIGHT system

My first response would be to address the room issues as others have mentioned. But you clearly state that since this is a living space your options there are limited. By far the easiest thing to do would be to experiment with different interconnects, although you don't mention what you're using currently so it's tough to make any recommendations at this point. But something like an Acoustic Zen Matrix Reference might do the trick, and it shouldn't cost you much more than shipping to give them a try. Best of luck.

These speakers are best driven by an amp that doubles power output as impedance is halved... so that the volume in the bass is equal to the volume in the mids and highs. Your Butler 2250 does not double power as impedance is halved.... The result is that the amp produces somewhat louder volume in the highs than it does in the bass, which causes a tonal imbalance that emphasizes the highs....

As long as an amp produces more decibels into higher impedances (treble region) than into lower impedances (bass region), the speaker will sound louder in the treble.

Tvad, this is one of the rare occasions on which I must disagree with you. Unless the amp is approaching the point at which it would be running out of either current capability or voltage swing capability, frequency response flatness will have nothing to do with the ability to double power into lower impedances. Basically, the amp will provide a flat frequency response into the speaker's frequency-dependent impedance as long as the amp's output impedance is low.

The 2250's output impedance (or equivalently, damping factor, which as I'm sure you know is output impedance divided into 8 ohms) does not appear to be specified. However, even though it is a no-feedback design, I would assume it is a small fraction of an ohm, which would result in just a small fraction of a db difference in voltage delivery into 4 ohms compared with 6 ohms or 8 ohms.

Any difference in power delivery which that may result in is a function of the speaker design, not the amp design, as long as the amp remains within its output current limitations, which it should as even the last line of your last post seems to indicate.

I think the posts by Johnny, Rich, and others about addressing the room issues are very well put and on the mark.

Regards,
-- Al

Buy headphones or move the system to a friendly room -- or get another system for a friendly room. Rooms can nearly make a system, and can easily kill one. Yours sounds to me like a killer.

By the way, I know nothing, and YMMV.

I'm in the 'room/set up problem camp' and fundamentally agree with Johnnyb53.

Appropriate acoustic 'treatment' would obviously be a great help but if you can't, you can't. But at least get an area rug on the floor between your chair and the speakers to kill the first floor reflection. That would be a good starting point.

Then, assuming that you are listening from a chair at the apex of a triangle, and your speakers are out into the room 4 to 5 ft from the wall behind, toe in your speakers until the axis of the speakers cross well in front of your listening chair. This will go a long way in eliminating 1st reflections off side walls and, since many speakers highs are substantially reduced when heard well off axis you will get some high frequency roll off as well. It might even help with floor reflections but no so much as a good thick area rug. FWIW it is tough to incorporate an audio system into a family living space without everybody making some substantial compromises.

I don't think a change of components would be a huge step forward for you unless you can do some thing with set up and acoustic issues.

FWIW.