Speakers known for great midrange.

Two of the best sounding set ups I've had were using Pass (an XP 10 pre and a 250.8 amp) with Harbeth. I had the 30.2 which were great - very detailed and neutral and uncannily good with voices- and then upgraded to the HLS5 Super which were amazing- really really musical and more involving, loved them. 

IMHO ATC. Harbeth and Spendor sound colored by comparison.

For the OP, ATC probably won't work if a syrupy coloration is what one is looking for.

Celestion sl6si if you can find a pair in good shape. Otherwise Wharfedale Linton or Harbeth ps3

I thought Vandersteen midrange was the best until I heard Tektons. Tekton are the best I've heard. Get the Moabs for 5k.

Listening to a pair of Harbeth 30.2xd’s with my INT 25 right now. SVS Micro 3000 sub. I upgraded from 30.1’s earlier this year. SL1200GR table, EAR 834p Phono pre. Dynavector 20x2L cartridge.

The Harbeth’s drop off pretty quickly below 54 hz, which is where the sub kicks in.

it’s a really nice “apartment “ system, and I mean that in a most positive way. I wouldn’t know where to go from here, in my listening area, with the music that I like.  My room is approximately 13.5 x 18 feet, speakers 24” from the wall on the long side. Jazz, acoustic music, guitar, piano, VOCALS, etc.