Speaker recommendation for married couple

Wow, she didn't like vocals on Harbeths and called them "flat?"
That's the first speaker I and many others would recommend if someone really cared about vocals on speakers.

I don't know what you do when the speaker probably most renowned for natural vocal range doesn't make the grade?   Good luck.  I think any recommendation is going to be essentially a shot in the dark.

(It's impossible for us to know if she was hearing what the various speakers can actually do, or if it was issues with set up, etc).

you need to get some room analysis software and pay attn to speaker & listener placement and room tmt

Just as another option, you may want to look into the single driver full range speakers the likes of Omega or Decware. I've only heard a couple of their models like the Decware DNA and Omega 3XRS and the vocals sounded incredible. They need very little power to come to life but may not be aesthetically pleasing depending on your taste. One other thing to keep in mind is tubes tend to generate a lot of heat and with a room that size, especially in an attic, you may find them uncomfortable during warm days. Good luck.

I would still recommend the Vandersteen's. Johnny Rutan can give you a great system.
FWIW, I have the Vandy Treo's, 2w subs, and Atma-Sphere amp and preamp and think it is about as good as it gets.
Bob

@celo - hum....my wife has very muscial ears and she never thought Harbeth were flat with vocals. In fact, far from it, it was the one area she though the speakers were very good. Same here, I always enjoyed the vocals with the C7s. I'm wondering if you have another weakness in your chain.  Did you mention your current amp and source?