Most “disappeared” speakers.

My current system with Lansche 4.1 also disappears although it is well beyond OP’s budget.

I agree with everybody that combination of front end, amplification, cables , room treatment and placement play in 3-D imaging or disappearing act.

But in general, planar speakers have advantage in wide and deep soundstage with disappearing act.

I recommend OP to try out Manepan LRS without any subwoofer whether it satisfy your need.

It may not rock but will be good for classical music or Jazz.

If you like LRS but if you want more dynamics or bass, then you can go for upper model or add subwoofer on it.

I also recommend OP to spend half of budget on digital front end or amplification.

Lyngdorf 2170 is very useful as DAC, D class int or pre amplifier and active crossover.

The new price starts from 4K$, but you can get used one around 3K$.

I wish you luck.

Thomas

2+ Georgehifi. 

+1 prof. Mbl or music culture. 

Apogee Duetta Signatures...or pretty much any Apogee. If you cand find them.

Agreed that almost any, or most decently designed speakers can "disappear."  Though some do it much more readily and successfully than others.