The first speakers I heard that completely changed my concept of what was possible was the Electrostatic Sound Systems (ESS) TranStatic I loudspeaker, in 1970. It had three RTR electrostatic tweeters, a KEF B139 woofer (the oval one Dave Wilson later used in his WAMM) loaded in a transmission-line enclosure, and a KEF 5" Bextrene midrange driver. FAR more transparent and uncolored than the AR, Rectilinear, JBL, etc. bookshelf speakers I had heard. But a pair retailed for $1200, far more than this starving musician had to spend on speakers. I already had an AR turntable with Shure M91e cartridge, AR integrated amp, and AR 4x speakers, and those would have to do for awhile.
The following year I heard the Infinity Servo-Static I. Even better, but $2000! By 1972 I had money to spend, and by then the original Magneplanar Tympani T-I was available. With a pair of them bi-amped with ARC amps, a Thorens TD-125 table with SME arm and Decca pickup, I finally had a system that satisfied. For awhile ;-)!