Hi-Fi TV Soundtracks (pre 1978) - Why?

[kfbkfb]

From the article "TV Sound at the Crossroads"
contained in the Fall 1973 Stereo magazine (USA):

Some (1973) TV audio section specifications:
Sylvania TVs: 47Hz-2kHz 36dB S/N
Magnavox TVs: 50Hz-9kHz 50dB S/N
Zenith TVs: 100Hz-4kHz 45dB S/N

(Network) Film/Video Tape sources:
to 7.5kHz or 12kHz

Musical content in the treble range wouldn't likely
be heard or would be severely attenuated.

1978 TV audio improvement (USA):
https://www.nytimes.com/1978/05/13/a...und-of-tv.html
^^^
This action by PBS goaded at&t into improving TV sound
distribution in the late 1970s.

Kirk Bayne