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Author Topic: Specifications of the Magnetic Sound? Christian Mueller Film Handler Posts: 3 From: Austria, Europe Registered: Nov 2001 posted 09-29-2003 03:47 AM                        Hi! First of all: This is my first Posting here. Big Compliment to the Producer(s) of this GREAT Site. Is one of my Favorite in the Net! My Question: Everyone knows everything about the conventional optical Dolby Formats and the three digital Sound Systems. But I'm not able to find any Specifications about the Magnetic Sound. Just: http://members.aol.com/cds3570/specs1.jpg and http://members.aol.com/cds3570/specs2.jpg But I really can't imagine that these Specs are correct. Can you tell me the true Specs and for example the Frequency Ranges of the 35mm-4-Track, 70mm-Conventional, 70mm-Dolby-A and 70mm-Dolby-SR Formats? Or the Dynamic Range, Distortion, Noise Level and Channel Separation of these Magnetic Sound Systems? Thanks a lot. Chris from Vienna  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 09-29-2003 10:19 AM                     There is a lot of variable involved and in many cases varried from sounding facility to another Also the oxide used made a big difference The Standard Formats for Comag prints were 35mm Format 20 35mm mag no nr no surround Format 21 35mm mag no nr with surround Format 22 35mm mag NR (dolbya) no surround Format 23 35mm mag NR (dolbyA) with surround 70mm Format 40 6 track toddao configuration no nr Format 41 6 track toddao configuration with nr (dolby a typical) Format 42 6 track with baby boom (LC RC bass info only) with nr (dolby a typical but could be SR no code number different though) Format 43 6 track with baby boom and split surrounds with NR (typically Dolby a but could be sr) The level of reference could be all over the place as well as the recording eq even though dolby applied acadmeny filters to all non nr formats some of the 4 track stuff in particular was wide range. The level is officially 50% modulation is 185nwb currently On a dubber full coat 35mm mag is up to 8 channels and the audio cyclopedia is the best source of response covverage with the SMPTE and CCIR curves discussed  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 09-29-2003 10:58 AM                     Gordon, is there a format number for mono mag on 35mm?  |  IP: Logged Christian Mueller Film Handler Posts: 3 From: Austria, Europe Registered: Nov 2001 posted 09-29-2003 11:25 AM                        Thanks for your Answer! And what do you think was/is the best possible Sound Performance of all Mag Formats? I guess 70mm-Dolby-SR? What Frequency Range, Distortion, Dynamic Range, Noise Level and Channel Separation was/is possible at the Best 70mm-Dolby-SR Presentation? quote: Gordon, is there a format number for mono mag on 35mm? Was there any Filmprint with mono Mag? I only know Magopticals incl. 4-Mag-Tracks and a very small optical Monotrack on the same 35mm-Print... Chris  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 09-29-2003 11:47 AM                     There was a mono mag combined format, but it was almost never used. I've seen it once. More common was a separate track.  |  IP: Logged Christian Mueller Film Handler Posts: 3 From: Austria, Europe Registered: Nov 2001 posted 09-29-2003 11:54 AM                        Which Filmtitles? And which of the 4 Mag-Tracks was it (maybe Track 2)? Chris  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 09-29-2003 12:04 PM                     I can't remember, it was many years ago, I remember that it was sent to a cinema which couldn't run it, and couldn't get another print in time, so they had to cancel a show, which suggests that it may have been mag only, but I'm not sure. the projectionist did show me a roll of film, but I can't even remember what perfs it had. This was when I was still at school, so it would be over thirty years ago.  |  IP: Logged Hugh McCullough Expert Film Handler Posts: 147 From: Old Coulsdon, Surrey, UK Registered: Jan 2003 posted 10-01-2003 04:11 PM                        Stephen. I believe the film that you are thinking of is 'Summer Holiday'. I remember showing this in mono mag with standard sprocket holes. There was a mono optical track under the mag stripe. The idea was that when cinemas equipped with mag had finished with the print the stripe was washed away leaving an optical track for use in non mag houses. This was the first film we showed at the ABC Croydon on the, then, new Philips FP20s that we had on evaluation test for philips. They also had the pulse discharge lamps. Hopeless for a 135ft throw. In theory if say a fuse blew we were supposed not to replace it, but to inform Philips and they would send an engineer down to find out why it blew. Oh yeah, we followed this instruction to the letter.  |  IP: Logged Peter Hall Master Film Handler Posts: 314 From: London, UK Registered: Dec 2000 posted 10-01-2003 11:40 PM                        Hugh - I note you have worked in the ABC Croydon - I guess you know but it closed a few weeks ago. Twas in a pretty sad state when it closed, with a very poor fourth screen (in the bar adjoining screen 2) never having seen much business. Curious to know when you were there - the site had obviously really been something in it's day (did it have 70mm in screen 2 and not screen 1?). Seats remained for the bulldozers, all projection gear stripped although the Westrex and Vitavox speakers, some stuffed with JBL drivers, remain Regards  |  IP: Logged Hugh McCullough Expert Film Handler Posts: 147 From: Old Coulsdon, Surrey, UK Registered: Jan 2003 posted 10-02-2003 06:47 AM                        Hello Peter. I was the Chief of the ABC Regal Purley, but used to run both the Purley, and Croydon cinemas when the Croydon Chief was away being stage manager on the live shows that some ABCs had at the time. Blackpool being one of these venues. The 70MM was, for some unknown reason, put into the smaller screen 2, and not, as one would expect, the large theatre No1. The only 70MM film I can remember being shown was 'Dr Zhivago', but there might have been others. The last time I was in the cinema was as a patron sometime in the middle 1970s. Can not remember what the film was. In the 60s it used to be used for stage shows, Bert Weeden, the Walker Brothers, and other pop stars of the day. At this time it was the ABC circuit southern England flagship. I never knew that a fourth screen had been added. By the way, I have not yet received my 16mm spacing.  |  IP: Logged

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