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Who Would LOVE White Christmas In 4K And Perspecta Sound For "Holly-days" 2022 (1 Viewer)

Vern Dias

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Theodore V Dias
I am not sure that everyone here understands exactly how Perspectasound works.

You start with one audio channel (mono), filter any content below 50 Hz (to avoid any interacttion with the keying frequencies), and mix it with 3 subaudible (only if the theatre strictly complies with academy curve) tones.
I've heard Perspecta prints played in certain (non Perspecta equipped) theatres that did not use the academy bass rolloff where you could clearly hear the constant rumble throughout the entire film.

The tones (30Hz, 35Hz, & 40Hz) are mixed in with the mono audio at varying levels corresponding to the desired gain to be applied to each (L, C, R) channel. IOW, the higher the level of the specific tone, the higher the level from the corresponding channel.

It's the responsibility of the Perspectasound integrator unit in the booth to respond to the level of each specific frequency tone and alter the gain of each channel based on the level of each tone.

None of this changes the fact that it is an optical track with its inherently limited high frequency response (maybe 6K on a good day using a perfectly adjusted sound head with no oil contamination on the scanning lens) and a limited low frequency range (50 Hz mandated by the fact that the control tones have to be filtered to avoid being audible in the auditorium).

With all these compromises, I'll take a BD audio track remastered from the stems any day. I suppose that if the studio had access to a mag element with the encoded tones, you could avoid the HF loss, but I'm pretty sure there is no way way around the 50 Hz restriction.

So, while having a Perspecta track included could be interesting for historical purposes, I doubt it would be the track an audiophile would choose in order to hear the highest quality audio.

Oh, yeah, I'm pretty sure that the White Christmas BD is stereo, not re-channeled mono. (But I'll have a listen later today to double check.) I was wrong, not sure where it sourced from.

Just my $.02 YMMV
 
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RobertMG

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I am not sure that everyone here understands exactly how Perspectasound works.

You start with one audio channel (mono), filter any content below 50 Hz (to avoid any interacttion with the keying frequencies), and mix it with 3 subaudible (only if the theatre strictly complies with academy curve) tones.
I've heard Perspecta prints played in certain (non Perspecta equipped) theatres that did not use the academy bass rolloff where you could clearly hear the constant rumble throughout the entire film.

The tones (30Hz, 35Hz, & 40Hz) are mixed in with the mono audio at varying levels corresponding to the desired gain to be applied to each (L, C, R) channel. IOW, the higher the level of the specific tone, the higher the level from the corresponding channel.

It's the responsibility of the Perspectasound integrator unit in the booth to respond to the level of each specific frequency tone and alter the gain of each channel based on the level of each tone.

None of this changes the fact that it is an optical track with its inherently limited high frequency response (maybe 6K on a good day using a perfectly adjusted sound head with no oil contamination on the scanning lens) and a limited low frequency range (50 Hz mandated by the fact that the control tones have to be filtered to avoid being audible in the auditorium).

With all these compromises, I'll take a BD audio track remastered from the stems any day. I suppose that if the studio had access to a mag element with the encoded tones, you could avoid the HF loss, but I'm pretty sure there is no way way around the 50 Hz restriction.

So, while having a Perspecta track included could be interesting for historical purposes, I doubt it would be the track an audiophile would choose in order to hear the highest quality audio.

Oh, yeah, I'm pretty sure that the White Christmas BD is stereo, not re-channeled mono. (But I'll have a listen later today to double check.) I was wrong, not sure where it sourced from.

Just my $.02 YMMV
I had thought the same thought the Laserdisc said it then when I posted the other thread I read the back of the Laserdisc jacket - not stereo when released 1954
 

RolandL

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List of some of the films that used the system - wow even GWTW 1954!
Some other films, such as Around the World in 80 Days (United Artists, 1956) also used Perspecta to convert their non-encoded mono optical soundtracks to three channel surround.

See also​


Watching The Power and The Prize 1957 from TCMHD. Perspecta is mentioned in the credits.
 

roxy1927

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vincent parisi
I'm very surprised that Kismet and Gigi were Perspecta as opposed to 4 channel stereo as these were deluxe Cinemascope film productions and a number of MGM around the same period were stereo. Especially Gigi which had Rolls Royce production values and was a roadshow presentation. Does 'also magnetic' mean it was also produced and presented in genuine stereo in certain markets?
 

Lord Dalek

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Joel Henderson
I'm very surprised that Kismet and Gigi were Perspecta as opposed to 4 channel stereo as these were deluxe Cinemascope film productions and a number of MGM around the same period were stereo. Especially Gigi which had Rolls Royce production values and was a roadshow presentation. Does 'also magnetic' mean it was also produced and presented in genuine stereo in certain markets?

Kismet, Gigi, and Forbidden Planet were all issued in 4-track Stereo with optical backup tracks. Said optical backup tracks were Perspecta encoded but are obviously grossly inferior to the magnetic mixes.
 

RobertMG

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Many first-run theaters had either one or both of the formats. MGM had installed Perspecta in all of their Loew’s theatres around the country.
Fascinating history all in an effort to get them off the couch and free tv and into theaters - tons of blockbusters in the 50's and mid 60's interestingly then the studios tanked till The Godfather, Jaws, Star Wars etc. All because the gov't decreed Studios could not own theaters - guess they did not get it the studios made films to supply their theaters
 

Jim*Tod

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I have a strip of a VistaVision horizontal print of STORY OF A PATRIOT from Williamsburg. The print actually was magnetically striped for the 6 track sound. That presentation which showed for years was a decidedly unique situation with dual theaters specifically designed with floor to ceiling curved screens. It ran for decades and was restored by Robert Harris to a more standard 70mm version about 20 years ago. Then later it was shown digitally. Sadly it is no longer being run at all. I lived in Williamsburg in the late 70's/early 80's and it was free to see the movie so I saw it many times.
 

Will Krupp

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Only VistaVision film made in actual stereo in the 50s was Williamsburg Story of a Patriot. Interlocked 6-track.

SILK STOCKINGS was credited as CinemaSope but I believe it was made with MGM's Panavision lenses (can anyone back me up on that?) and Perspecta.
 

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