See Also: What is SDDS? (courtesy the official SDDS site) (Alan Jay)

SDDS - Sony Dynamic Digital Sound

Date: 12 Jul 1993 09:29:15 +0100
Newsgroups: rec.arts.movies
Subject: SDDS [Sony Dynamic Digital Sound (TM)]. (long)

by Alan Jay (c) Copyright 1993

SDDS [Sony Dynamic Digital Sound (TM)].

Sunday morning I had the pleasure to hear the latest in the line of Digital Film formats. At a special screening of "In The Line of Fire" at the Odeon Marble Arch (London, UK). I also spoke to a number of the developers of the system, which according to them, has gone from the drawing board to having 4 cinemas equipped with the prototype in under 6 months. Talking to the main designer of the sound system the following seemed to me to be the most interesting. As has been mentioned before the system has the capability of up to 8 discrete tracks and uses a 5:1 compression technique (probably based on that of the mini-disk from Sony) and the writing algorithm maintains 100% data redundancy so enabling quite large flaws in the print to be survived. Already they have run prints 500+ times without noticeable loss. How does this specification compare with other on-film digital systems Dolby SR-D and the now defunct CDS system. Dolby SR-D has a 10:1 compression ratio and from my experience can fall back to the standard SR mode too easily (one print I saw cracked and popped its way along most annoyingly on a couple of occasions). SR-D also only has 5.1 discrete tracks (I think). CDS on the other hand had a similar 1:5 or 6 (?) compression ratio but because of its lack of optical tracks made print production and inventory control difficult. Sony representatives also stated that they are very aware that the system must be able to be completely dealt with and optically printed at the mix down studio and not require special facilities. Also that when the system becomes widely available in the 2nd quarter of 94 that they hope that all prints of say a 2,500 run will be SDDS. SDDS seems to be aimed to provide complete compatibility with any setup, the system although inherently 8 track can have 4 or 6 discrete track mixes placed on the system and the decode electronics will interpolate and spread sound to other channels if available without user intervention. The reverse is also true the system can be used in 4 and 6 track auditoria and the system will happily convert the data correctly again without the operating having to do anything. Most noticeable this would be a house with 6 track (3 speakers behind the screen) where the left center and right centre tracks can be mixed into left/right and centre channels to give phantom left/right centre speakers. This leads Sony to claim that the system can be all things to all people, providing digital grade sound in a range of auditoria with a standard release format that is backward compatible with the current Dolby optical surround systems. How did it sound? Well I was reasonably impressed, although "In the Line of Fire" was mixed 6 track the extra screen channels gave an extra width to the picture and voice track which was very nice but I suspect missed by most of the listeners. Having the split left and right surround channels has noticeable advantages. Overall the sound quality was more than acceptable for a cinema experience (a slight loss of high frequencies that I felt was most likely due to the cinema speakers rather than inherent to the format, also the noisy air conditioning unit wasn't heard by my companions but was also noticed by the Sony technical staff). One of the designers, a sound mixer, said that the reason he wanted an 8 track system was that when he remembers mixing in the 70s when 6 track mixes were for 5 speakers behind the screen and a mono surround track it gave composers and directors the opportunity to fill the space in front of the screen in a way that it is impossible to achieve with 3 speakers (especially in wide screen movies 2.x:1 Panavision etc). And that this flexibility was why he insisted on a full 8 track system. The other fun story behind the development of SDDS is that the people involved in the US went to the hardware side of Sony in Japan and asked for them to become involved in the project the people in the hardware business wanted to know how many million units they could hope to sell. After a little persuading they cottoned onto the idea and different initial market size and now have seen the synergy between Sony as a hardware company and their US software arm and see this as the medium of the future with an eventual goal of providing this level of sound to the Home Theatre Market (but don't hold your breath). Also I was told that DTS promised Steven Spielberg 1000 DTS units installed at the launch of Jurassic Park and managed 700, still not bad but only 700 out of the 2,400 showing the movie. Overall I think this is an interesting system that seems to be providing a universal release format and backward compatibility. If the price is right when it is fully launched next year then things could be interesting. I was told that Dolby have reduced the price of SR-D installations since the announcement of the system. SDDS is seen as a competitor to SR-D primarily and not against DTS. How this compares to the DTS system I don't know but I suspect that an offboard system will be considered as yet another thing to go wrong by exhibitors. Only time will tell. Sony's view seems to be to persuade exhibitors to do nothing for a year until things start to settle. I'm looking forward to more digital sound in the cinema. ------------ And now the credits: 35mm SDDS film has the digital tracks outside the sprocket holes on both sides of the film ie: __Digital track | | _Optical Track ____Digital Track | | | \/ \/ \/ DD[] XXOOOOOOOOOOO []DD DD XXOOOOOOOOOOO DD DD[] XXOOOOOOOOOOO []DD DD XXOOOOOOOOOOO DD DD[] XXOOOOOOOOOOO []DD DD XXOOOOOOOOOOO DD DD[] XXOOOOOOOOOOO []DD ^ ^ ^ | Image | | | --Sprocket holes-- Preliminary Specification from data sheet: Analogue Outputs: Left, Left Centre, Centre Right, Right Center, Sub Woofer, Left Surround, Right Surround 8x +4dBs, <100 Ohms, Balanced, XLR3 M (+24dBs max) Frequency Range 8x 5-20,000Hz Dynamic Range 8x 105bB Wow & Flutter Immeasurable The system also comes with auto changeover between projectors (if required), remote control and analogue bypass inputs. Mix & Theatre formats: The system can be mixed in 8 discrete, 6 discrete, 5.1 discrete and 4 discrete channels. The system can be played in the theatre in 8 discrete, 6 discrete, 5.1 discrete and 4 discrete channels. Any dub stage format listed above can be played on any Theatre reproduction system listed above the electronics doing the best conversion possible without operator intervention. The system will be released in early 1994 and kits will be available to dubbing studios and film printers to adapt industry standard film printing equipment so as to provide an easy ability to record and print SDDS films. Then they will try to sell the idea of installing the system to your local theatre. They will also be allowing 'any' studio to use the technology it will not be limited to Columbia, Tristar. Currently if you live in LA or New York there are two cinemas in each kitted out with prototype systems showing "The Last Action Hero" and "In the Line of Fire". In the UK hold your breath for 1994... though they were courting the head of MGM cinemas this weekend and now doubt the Odeon chain as well. On a final note I think that the SDDS promo (which is good) is still not up to the Dolby SR-D train. Overall I am not sure that the general cinema going public will be able to tell the difference. I can and will go out of my way to see a digital format or 70mm print but we are the exception. Lets hope that one of the formats becomes widely available because the advance over standard Dolby Surround is enormous. Last week I saw a Dolby SR print of Cliffhanger also at the Odeon Marble Arch and would say that the advantages of a this analogue technology over say a 4 track lossy digital technology are not noticeable except to the film and sound buff. More channels give noticeable effects that are easier to quantify and so can be noticed by the general public weather they will go out of their way to see digital sound systems is another matter that I am yet to be convinced by. Personally I hope they are, as there are improvements to be achieved over standard optical film sound tracks and I am looking forward to seeing and hearing more digital film.
For more information: Sony Dynamic Digital Sound Inc 10202 West Washington Boulevard, Culver City, CALIFORNIA 90232- 1395. Tel 1 (310) 280 5777 Fax 1 (310) 280-2024. by Alan Jay (c) Copyright 1993 July 11th Tel: +44 (0)81 863 1191 Fax: +44 (0)81 863 6095 PS I enjoyed "In the Line of Fire" good thriller, Clint hold the piece together well and John Malcovich is excellent. -- ALan Jay, PC User Group, PO Box 360, HARROW HA1 4LQ, ENGLAND Tel: +44 (0)81 863 1191 Fax: +44 (0)81 863 6095 [+ Usual Disclaimer - I didn't say it, can't spell and dysleexia rules KO]