If high volume levels are not required, try the Merlins (mine are VSM SE) with a 300b set amp. I used the Cary monoblocks. This is the best vocal reproduction I've ever acheived and I've owned (or still own) a bunch of the speakers listed on this thread (including the Verity, Maggies (3.5) and Silverline Sonatina). While I'd still choose the Parsifal Encore overall, the Merlins are hard to beat for vocals, IMHO.
Another interesting way to go is to choose one speaker for overall performance and add a second, limited bandwith pair for vocals. Some of the single driver or minimalist crossover designs (e.g. deCapo MM) acheive excellent mid band performance at modest cost by trading away performance at the edges. On the theory that no single design does all things best, your budget would put ca. $2500 toward these and would still leave app. $12,500 for a pair of very dynamic full range speakers of your choosing.
Another interesting way to go is to choose one speaker for overall performance and add a second, limited bandwith pair for vocals. Some of the single driver or minimalist crossover designs (e.g. deCapo MM) acheive excellent mid band performance at modest cost by trading away performance at the edges. On the theory that no single design does all things best, your budget would put ca. $2500 toward these and would still leave app. $12,500 for a pair of very dynamic full range speakers of your choosing.