I've had several monitors "disappear" in various rooms and setups. A/D/S L500s did it in the mid-70's, Morel M202s in the 80's, Boston Acoustics VRM50s in the 90's. All had 6" to 8" woofers and 1" domes, some soft and damped, some hard and metallic. All were on sturdy metal stands away from room boundaries in well proportioned spaces. For $2K/pair, the BMR Monitors are what I'd look at, but the GR Encore XLS maxxed out would also interest me. For much less, if you're a DIY guy, the Morel Ardon kit from Parts Express ($800.00/pair + veneer = well under $1K) is a textbook monitor.
Bookshelf speakers that renders 3D soundstage
Recently I am on a quest to find a pair of bookshelf speakers under $2k that will render 3D soundstage. The soundstage does not need to be much wider than the speakers that are approximately 7-8 ft apart but, within the soundstage, I am particularly looking for the decent depth, focus image and pinpoint instrument/vocal separation. The other sound trait I am particularly looking for is the nimble, agile bass that could go down to around 45 Hz -3dB. The pairing amplification is going to be Parasound A23. If you have experienced / auditioned that, please let me know.