Certainly there was a breakthrough by the early 50's. People would run around to the various HIFI (monophonic then) shops with Toscannini's (sp?) Pictures tucked under their arms to hear it on one of the big speaker systems. I think a major development was Edgar Vilcher's AR speaker design as a competitor to the big folded horn systems then so common.
I lived in the beach area of LA, and a neighbor had a JBL folded horn, Gerrard (sp?) with variable reluctance cartridge, an amp with separate power supply he's designed, and a few Capitol FDS LPs. What a revelation for a teenager using an RCA 45 RPM through his Fender amp. I was hooked. I think my love of audio equipment led me to get a doctorate in psychoacoutics, rather than any real interest in hearing.
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I lived in the beach area of LA, and a neighbor had a JBL folded horn, Gerrard (sp?) with variable reluctance cartridge, an amp with separate power supply he's designed, and a few Capitol FDS LPs. What a revelation for a teenager using an RCA 45 RPM through his Fender amp. I was hooked. I think my love of audio equipment led me to get a doctorate in psychoacoutics, rather than any real interest in hearing.
db