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

[old_tv_nut]

Originally Posted by 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

I'd bet that these frequency responses were improperly measured as the electrical response at the speaker. Due to the small speakers in TV sets, the high frequencies were rolled off to get a flatter acoustic response. (This also served to attenuate any 15,750 Hz horizontal sweep energy that got into the audio).

[kfbkfb]

https://www.americanradiohistory.com...ng-1973-12.pdf

Letter on page 10 (about NYC originated, LA broadcast):

"But locally on the air it appeared to be compressed
and have incredible high frequency distortion."

I don't know how much of the sound quality decrease
was due to the national TV audio distribution system
and how much was due to the local TV station.

Kirk Bayne