Speakers under $5000 maintained a reputation for quality sound over the last 15 years.

Sonus Faber, Thiel. Many models, from both companies, can be found used for less than $5,000 in today’s market.

If we’re including pre-loved speakers, amongst established brands i’d include Klipsch, Harbeth, Devore Fidelity, Joseph Audio, Magnepan and Martin Logan. In newer players, Gold Note.

Vandersteen +2
Magnepan, Shahinian, Quad, ProAc are a few others.
B

Ohm Walsh, JBL, Klipsch, another +1 for Vandies, SoundLab, Bowers & Wilkinson, Sonus Faber, Ascend Acoustics, Salk, Selah.

I've owned at least one from except SoundLab... some day, some day