STUDIO

4 The sample rate converter is used to take digital audio fromthe digital 1 inch machine -either 48 kHz or 44.1 kHz. If the jobis to make a 1630 copy, it will require a sample rate conversionfrom 48 kHz down to 44.1 kHz. Other clients require 1630recorded on 1 inch NTSC video tape and not '/a inch video tape.A typical programme would involve playing back on 1 inch PALvideo tape plus a 1630 44.1 kHz tape. The picture would begoing through a standards converter and recorded on an NTSC1 inch machine; meanwhile the sound would be going through asample rate converter to 44.056 kHz and then coded back to1630 format and recorded on a second NTSC 1 inch machine.This complex procedure involves four tape transports, a picturestandards converter as well as an audio sample rate converter.It can be offered by the united strengths of Ultrasound andDoublevision and is, in Woolley's opinion one of theirundeniable advantages over the competition."I don't think anyone else in town can offer those kind offacilities. It is quite popular with American VHS duplicationplants. They would like to run their video from 1 inch and theiraudio from a PCM1630, also on 1 inch. They prefer to have the1630 on 1 inch firstly because the tapes can go up to 3 hourslong compared with the 3/a in which is about 75 minutes, andsecondly because they then have two similar tape transportsthat can be controlled more easily as a pair."There are three headblocks for the Perfectone 16/35 magneticmachine."On 16 mm we run 'centre & edge' a 2 -track system whichgives you one good track and one medium track. In 35 mm thereare two interchange formats (a) triple track and (b) four tracksacross the width of the tape. Film dubbing theatres usemachines with many more tracks but when people are sendingmaster tapes around they are either 3 -track for stereo or 4- track.000000 00000 Uaaánex®çtaaeorsaaa aaraaaa(aññeeáarssaoresaaaaaaaaGaaaaaaaa.09aatltlaa aaaIel wawapoilaan1116 SAM ,bïrAAdams -Smith AV26OO synchronisation system with the Sonyautolocate76 Studio Sound, June 1989Four track is used mainly for LCR tracks which willsubsequently he matrixed together into the two Dolby Stereotracks."The discrete and matrixed tapes are interchangeable. You getdiscrete left, centre, right and surround on the 4 -track tape oron the triple you get what Dolby Stereo call left total and righttotal; these are decoded to be left, centre, right surround in thecinema. For CIC films we master maybe three titles a month inperhaps five languages each for video release. They will send us12 cans per film per language. Those are normally the 3 -trackformat (left total and right total) and we edit those 12 reelstogether and relay them onto the video master tapes. That's amajor contract for us, which doesn't involve our mainstudio /control room."Ultrasound has been Dolby approved for Dolby Stereo dubbingof film soundtracks -an aspect of work which the company hopesto develop further, having worked on a couple of short projectsalready. Dolby approval is required since the processors are notavailable for sale, being lodged with studios to use them onproductions where a contract has been made and a royaltynegotiated. In order to earn approval a studio hosts a visit fromDolby engineers whom they must satisfy that their methods,listening environment, desk, and monitoring etc are suitable."We were a little bit unusual since all of our equipment isdigital and the Dolby Stereo masters are more usually recordedon 35 mm magnetic. 'We don't usually do it like that' seems tobe a fairly stock response from people in the film industry. Andthere was a procedural restriction that meant that because ourdigital master was going to be the 'Dolby Stereo printingmaster' it had to be Dolby A encoded, even though we weregoing to present it on PCM1630. It doesn't really make anysense but nevertheless that was the way that it had to be. Thosetapes were then taken to Abbey Road for transfer from 1630 to35 mm."The control room monitoring is expanded during Dolby Stereosessions. A third, centre, Genelec monitor is required plus a pairof speakers at the back of the control room for the surroundchannel."Something like Yamaha NS10s are sufficient for the rearpair of speakers. The surround channel is frequency limited tobetween 100 Hz and 6 kHz or something; there isn't a great dealgoing back there."With timecode DAT now a reality in the Fostex D -20 Woolleyis already well advanced down that road. They are currentlyworking on a series of six 1 -hour long episodes for Channel 4,shot on 16 mm film and recorded on a Sony PCM2000 DATmachine. The tapes come back to Ultrasound to be striped withEBU timecode on the Fostex D -20 which has an interface to theAdams Smith controller. Those same DAT tapes are thentransferred onto 16 mm magnetic with timecode on the edgetrack. The film editor listens only to the audio track and whilstmaking his razor blade edits in the audio track will also cut thetimecode track. These cuts relate directly back to the FostexD-20 timecodes they started out with which can now be autoassembled digitally from the DAT onto the PCM3324."The technique has equal applications in trying to offer digitalaudio for programmes that have already been cut in video editsuites. Ampex, CMX or ISC format floppy disks can all be fedinto the AV system. By being more open minded and flexibletechnically we can now offer to reconform from people's originalaudio master tapes. That is something which has been far tootime consuming to consider with older synchronisers where youhave to enter in all the numbers manually on a keypad -youjust wouldn't do it; it would take you far too long and cost fartoo much money. Having the edits loaded into the machineautomatically is a far more attractive proposition. It really isworth going back to the original tapes. I am convinced thatsooner or later the feature film industry will move away from35 mm magnetic sound recording and use more digital audiotechniques. I would like to be involved in that."Film editors generally are able to spend more time beingcreative, deliberating over editorial changes, paying attention todetail as the facilities are less expensive than those in audiopost -production. Digital audio can offer superior quality to the16 mm magnetic in every generation but until now there hasn'tbeen a workable system to allow the marriage of these twotechniques."What I think we've found now is some way to meet half wayand accommodate productions who want to edit on film. We canvery quickly and efficiently spin through and recreate all thoseedits using the digital master tapes due to the very good editlist management and edit list interchange we've beendeveloping with this Adams Smith machine. When you use theauto assembly function, as long as you keep putting the rightplay tapes in it goes through and recreates all the edits as theyhappened in 16 mm. That is a very good offer we can make toproducers: better sound quality without imposing completelynew work methods. There is no doubt in my mind that thedigital audio equipment is far superior, especially in multigeneration film productions. "Ultrasound, 2 Golden Square, London Wl, UK. Tel: 01.4397138.