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

[kfbkfb]

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm
^^^
...a cymbal crash shows no sign of running out of energy at 100 kHz.

I was actually wondering if anyone mentioned to TV soundtrack
(theme music and music in the episodes) composers that, due to
technical limitations, some/most of the harmonics of certain
instruments wouldn't be heard by home TV listeners (using those
instruments for dramatic effect might not have the desired result)?

Kirk Bayne

[old_tv_nut]

Originally Posted by kfbkfb

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm
^^^
...a cymbal crash shows no sign of running out of energy at 100 kHz.

I was actually wondering if anyone mentioned to TV soundtrack
(theme music and music in the episodes) composers that, due to
technical limitations, some/most of the harmonics of certain
instruments wouldn't be heard by home TV listeners (using those
instruments for dramatic effect might not have the desired result)?

Kirk Bayne

Trying to accommodate a wide range of possible degradation would be foolish, and could result in distorting the frequency response of what could get through. Better to master for reasonable limitations, and if the transmission path or particular home receiver were worse, so be it. (Of course, you would not produce something where the plot depended on the possibly missing or unheard highs - thus, a fake lower-frequency mosquito buzz if it was essential to the plot.)

[Mi40793]

The quoted May 13, 1978 NYT article on DATE says 62 stations had bought receive equipment. It was an expensive box .

DATE was 4 audio channels, 15 kHz, 16bit, mux’d onto ~5.5 Mhz QPSK carrier, intended to ride above the video.

To my knowledge DATE was never used on the ATT terrestrial microwave system used for PBS video. ATT would not allow DATE on the terrestrial microwave links, serving a limited number of PBS stations, as it ‘violated ATT tariffs’.

This dispute led to PBS obtaining money from CPB to build their own complete network satellite distribution system, in service Sept 1978. It included over 300 downlink dish/antenna receivers (FM video and one channel FM subcarrier for mono 15khz audio) and a ground uplink station Springfield, Va., and leasing Western LC Union satellite transponders. This allowed PBS stations to receive stereo programs (not all programs were stereo) via DATE if they purchased a decoder, or FM mono if not. NPR used the other two DATE channels. The cost of the complete PBS satellite system was equivalent to 10 years of ATT microwave line charges at 1978 rates.

The ‘big three’ networks used 5kHz telephone circuits for audio until ~1978 when ATT added FM subcarriers providing 15kHz audio. ATT used Farinon FM modulators above the video at about 5-5.5 MHz.

Quad tape audio at 15 ips would do 15 kHz.
16mm television film projectors, ~6 or 7 kHz (best I ever saw)
TV station audio transmitter, audio path, etc., 15 kHz, same as any FM radio station required.

Working at two networks, everything audio was kept as flat a response as possible, with agc and peak limiting at transmitters.

[W.B.]

Originally Posted by Mi40793

The ‘big three’ networks used 5kHz telephone circuits for audio until ~1978 when ATT added FM subcarriers providing 15kHz audio. ATT used Farinon FM modulators above the video at about 5-5.5 MHz.

Quad tape audio at 15 ips would do 15 kHz.
16mm television film projectors, ~6 or 7 kHz (best I ever saw)
TV station audio transmitter, audio path, etc., 15 kHz, same as any FM radio station required.

Working at two networks, everything audio was kept as flat a response as possible, with agc and peak limiting at transmitters.

Between Jan. 26 and Feb. 26, 1978, from what I have read, was the period when the transition from the old 100 Hz-5 kHz telco audio to the diplexing system that allowed 50 Hz-15 kHz audio transmission was effected. Apparently the later date was when the old telco audio was shut off permanently.

[Eric H]

The Music and often dialog for filmed shows would have been recorded separately from the film, the Music would have been done in a studio to the same standard as any other music recording, it would have been put together later in post production.

This is why they can remaster movies and TV shows years later with upgraded audio mixes.

[Mi40793]

The quoted May 13, 1978 NYT article on PBS developed DATE (Digital Audio for Television) says 62 stations had bought receive equipment. It was an expensive box.

DATE was 4 audio channels, 15 kHz, 16bit, mux’d onto ~5.5 Mhz QPSK carrier, intended to ride above the video.

To my knowledge DATE was never used on the ATT terrestrial microwave system used for PBS video. ATT would not allow DATE on the terrestrial microwave links, serving a limited number of PBS stations, as it ‘violated ATT tariffs’.

This dispute led to PBS obtaining money from CPB to build their own complete network satellite distribution system, in service Sept 1978. It included over 300 downlink dish/antenna receivers (FM video and one channel FM subcarrier for mono 15khz audio) and a ground uplink station Springfield, Va., and leasing Western Union satellite transponders. This allowed PBS stations to receive stereo programs (not all programs were stereo) via DATE, if they purchased a decoder, or FM mono if not. NPR used the other two DATE channels. The cost of the complete PBS satellite system was equivalent to 10 years of ATT microwave line charges at 1978 rates.

The ‘big three’ networks used 5kHz telephone circuits for audio until ~1978 when ATT added FM subcarriers providing 15kHz audio. ATT used Farinon FM modulators above the video at about 5-5.5 MHz.

Quad tape audio at 15 ips would do 15 kHz.
16mm television film projectors, ~6 or 7 kHz (best I ever saw)
TV station audio transmitter, audio path, etc., 15 kHz, same as any FM radio station required.

Working at two networks, everything audio was kept as flat a response as possible, with conventional agc and peak limiting at TV transmitters.

[ChrisW6ATV]

OK. All of this is quite interesting.

[kfbkfb]

https://www.bbceng.info/Technical%20...digits-fm.html
^^^
On the 14th of September 1972 the link from Broadcasting House to the Wrotham transmitter switched to the new BBC PCM (Pulse Code Modulation) system.


I had read about the BBC using PCM for national FM audio distribution (funnily, when the CD appeared in ~1982, some complained that 16 bits wasn't enough, they were reminded that they had been listening to 13 bit PCM since ~1972)


Kirk Bayne

[KentTeffeteller]

Other big reason for HiFi soundtracks. Music and concert shows. Which also before MTS were simulcast by FM Stereo stations.

[kfbkfb]

https://bayarearadio.org/sf-radio-history/netsnd
^^^
A few stations in extremely small markets used 3.5 kHz circuits.


(just found this, provides some background about national audio distribution)


Kirk Bayne

[Kevin Kuehn]

From the title I thought the discussion was going to be more along the lines of "Why bother with Hi Fidelity Soundtracks?". A lot of us old guys would be lucky if we can hear much above 8khz. Fortunately for us there's not much intelligence up there that keeps us from surviving.
Good music still sounds just fine.

[kfbkfb]

I guess my question could be summed up as:

The limitations of the (USA) radio and TV national audio distribution systems were well known, did anyone tell the composers about the limitations?


Kirk Bayne

[Kevin Kuehn]

Do you seriously think there was a conspiracy? For a reality check consider all the folks today listing to music and video soundtracks on their teeny weeny cell phone speakers. Do you think they know what they are missing, or even care to plug in an ear bud?

[kfbkfb]

Originally Posted by Kevin Kuehn

Do you seriously think there was a conspiracy?

AFAIK, the limited frequency response of the USA national audio distribution system existed since the first (AM) radio network was set up, it's just interesting to me that, after ~40 years of (known?) poor fidelity, a composer would use instruments (musical bells in the VTTBOTS case) that almost no TV viewer would hear.


Kirk Bayne

[Electronic M]

Originally Posted by kfbkfb

I guess my question could be summed up as:

The limitations of the (USA) radio and TV national audio distribution systems were well known, did anyone tell the composers about the limitations?


Kirk Bayne

Given the fidelity limitations were on the transmitter end, NO TV could make it sound better than it was....Thus if the composers owned TVs or spent enough time around someone else's TV logically they should be able to hear for themselves how limited the medium was....All except for Bethoven.