You think recording tech hasn't advanced since 1959? That Belefonte recording is not great. The vocal is the only thing that has any detail and its distorted and sibilant in places.Listen to this recording from 1959 and tell me what you hear was recorded with equipment "in its adolescence."
Belafonte at Carnegie Hall - Wikipedia
en.wikipedia.org
If you read the history of audio-recording you will know that by 1955 the recording systems had reached the zenith that we call Hi-Fi. There were even 8-track recorders in use by 1955. Hi-Fi followed a decade later when it became cheaper to produce that technology not to improve it.
From 1994.
Hear a difference?