Q-Sheet: Thomas The Tank Engine:

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1 Q-Sheet: This is my third article for AudioMedia offering a "hands-on" review of Macintosh hardware and software for Video Post-Production. The first article looked at Mark of the Unicorn products such as the Video Time Piece and Performer sequencer; the second compared Cue and Clicktracks film composer's software; and this article will look at Digidesign's Q-sheet A/V software working with Sound Tools. As the A/V (for Audio-Visual) part of the name suggests, this software provides a cue sheet or edit decision list for putting audio to picture. Q-Sheet lets you organise the playback of your samples from a MIDI sampler, audio files from your hard disk, and MIDI files created via your MIDI sequencer. You put these into a list format, called an Edit Decision List, showing the SMPTE times for each item corresponding to the picture frames where these events should take place, or start playing from. Automated faders can be set up to control the volumes or other parameters of your MIDI devices from the tracks in Q-Sheet. You can also automate MIDI controllable mixers, such as the Yamaha DMP7, and MIDI controllable FX units such as the SPX90, using visual representation of faders, switches, and other controls on screen. As fate would have it, just at the time I was discussing this review with Ian Gilby, I was hired in to use Q-sheet to lay up the sound effects, dialogue, and music to the popular children's video, "Thomas The Tank Engine". This afforded me with an ideal opportunity to describe exactly how Q-Sheet worked out on a 'real-life' project! Thomas The Tank Engine: Gavin Beckwith and Gary Dixon recently launched a new Audio-for-Video production company called Ga-Ga Productions when they won a contract from Britt Allcroft Ltd (the producers of 'Thomas') to work on the third series of 'Thomas' programs, TTTE III. 16 episodes were proposed, with a further 10 provisionally planned. Gavin spent a week or so gathering together the original sound effects from the previous series onto DAT cassettes, and transferring them into Sound Tools. He brought me about 400Mb of these in Sound Designer II format, which I transferred to my DAC 780 MB hard disk. I was supplied with sixteen 1/4", 7.5 ips tapes with additional FX, and with three more DAT cassettes full of fx. So, I spent the first two weeks transferring these into Sound Tools, and setting up Q-Sheet files for each episode. Britt Allcroft supplied 'breakout' sheets with a provisional list of the sound effects required for each episode, and a copy of the script for each episode. I simply arranged the effects in order in Q-Sheet, with short gaps between each, so that Gavin and I could check their suitability. Very quickly, I filled the entire 650MB formatted DAC disk. I realised that I would need additional disk space for room to work. I also realized that it would be inconvenient and time consuming to back up the SFX files to DAT, as they were all in different folders, and the DAT backup software from Digidesign won't let you do a batch backup from separate folders. I would have preferred to back up to optical, but this is still quite an expensive option! My 45MB removable Syquest came in handy for moving stuff around, but wasn't really large

2 enough. Gavin also had a DAC 780Mb, so we backed up everything from my disk to his, and the intention was to take this to an optical drive and back up to a cartridge, or to put all the fx into one folder and back up to DAT. We decided to transfer the SFX from Sound Tools into an Akai S1000PB, so that we could have several playing at once, such as a background atmosphere with some particular sounds - like a train sound and a whistle sounding at the same time. This was not really possible from Q-Sheet, as the Sound Tools system only provides two separate outputs (although we could have mixed various sound effects together using Sound Tools - but we wanted easy control over all the effects up until the final mix). The dialogue and music would be in mono, so these would use one Mono track each via Sound Tools. We used a 200 Mb DAC drive with the S1000Pb, and had 20Mb of RAM installed. This amount of RAM proved to be just about adequate to hold all the samples for one episode, but, due to the limitations on the number of key groups, samples, and programs in the S1000, we could not access the last 10% or so of RAM. I felt that we should have had a full 32Mb of RAM installed in the S1000, to allow plenty of room to play with. I synchronized up a U-matic 5850 VCR using VITC with a Video Time Piece to convert this to MTC, which was then sent to a MIDI Time Piece to interface with Q-Sheet on the Macintosh. Episode 16 was the first we worked on, and some problems immediately surfaced which we had to overcome while we were transferring samples from the Mac to the S1000. We had to keep re-configuring the SCSI connection between the S1000/200Mb and between the S1000/Macintosh by walking round the back of the equipment and re-plugging. The first half dozen or so times we did this on the first afternoon, we didn't mind too much, but when we had to change the connections about 15 or twenty times on the second day, I realised why DAC produced a system on their rackmounted hard disks which lets you connect both Mac and S1000 via SCSI to various hard disks, and switch between these from a hard disk drive's front panel! It was also very obvious that we needed a remote for the video player! Fortunately, Gary Dixon (who was extremely keen to have everything working at maximum efficiency) organized a remote for the VCR and a modification to the DAC 200Mb hard disk as soon as we realized this! The next thing that happened was that some of the last samples we transferred to the S1000 played back severely distorted when we still had about 10% memory free. I realized that we had used a couple of programs, each with 76 key groups, and about 30 samples in memory. When we removed all unused key groups and samples, and reduced the sizes of the samples to the absolute minimums, everything fitted comfortably with no problems. Once everything was allocated to suitable MIDI note numbers and so forth, we were able to start laying these up to picture at last! Now it got easier! When we had constructed just the right sequence of effects to suit a train pulling up and stopping, and a bridge collapsing into a fast-flowing river, I got my first real 'buzz'. Up till this point I had found things a little tedious - especially having to work on the S1000 with its fiddly buttons and tiny screen! Working in Q-Sheet was, by contrast, a dream! A popup keyboard lets you assign the MIDI Note number for each event you have inserted, and clicking

3 on any SMPTE in-time or out-time brings up a dialogue box to let you alter these. We put a long 'Wind' atmosphere in to cover the time the trains were in a deserted quarry, for instance, and here we were able to use one of Q- Sheet's automated faders to control the volume of this. To set this up, you just drag a fader onto the Automation Window from a palette at the left, click on it to access its parameters, and set it to control MIDI Controller 7, which controls MIDI Volume - a piece of cake really! We had to create our own spotting notes or EDL by watching the episodes supplied on U-Matic with burnt-in timecode. For the first episode, we wrote a rough list of these on a pad, then typed them into Q-Sheet's EDL, and finally went through in sync with the picture and corrected all the times. For the subsequent episodes, it proved quicker to work directly to picture, in several passes, till we had spotted and filled in all the effects. One of the more timeconsuming tasks was to match up the unmarked engine and whistle sound effects to those used on the original two series of 'Thomas'. This had to be done by 'ear', listening to VHS tapes of original episodes and comparing these with the effects supplied. Also, a couple of new sound effects had to be created from scratch, and my DX7II came in handy here for Diesel's and Mavis's engine whines! At the time of writing, the mixing was being done mostly in Q-Sheet. However, the longer-term plan was to use some combination of Yamaha DMP7/DMP11/DMP7D or MotU Mixer 7s's straight to Fostex D20 DAT recorder. We figured that we would be able to do a nearly-all-digital mix if we used a DMP7D with the Fostex D20! We also discussed using SampleCell cards, and Pro Tools as alternatives for the Macintosh system. Pro-Tools would be more suitable, especially for stereo work, and SampleCell cards would have been more convenient than the S1000 in some ways, although their 8Mb RAM limit would probably dictate the use of three or even four of these to match the RAM capabilities of the S1000. The music was to be supplied on centre-track time-coded 1/4" tapes which would be transferred to DAT, then digitized onto hard disk to be played from Q-Sheet's EDL via Sound Tools. The dialogue would be handled similarly, and would ideally be supplied on time-coded DAT. One possibility would be to run the music and dialogue from time-coded 1/4" and DAT machines in sync with the Macintosh via SMPTE, although this would be a more costly option involving the purchase or hire of additional DAT and 1/4" machines with suitable machine synchronization facilities, such as the Fostex models. General Program Features: It can be difficult to put across all the features of a piece of sophisticated software in print, but here goes! Q-Sheet is an Event Sequencer with SMPTE sync. It may be used for MIDI automation and for Audio Post-Production for Video and Film. Like a music sequencer, Q-Sheet organises sequence data into tracks. Unlike a music sequencer, you do not enter musical notes onto particular beat locations within a musical bar, but instead you enter MIDI events against particular SMPTE time locations throughout the duration of the piece. You then combine one or more tracks to create a cue-list. The cue list format is often used in studio automation and electronic video editing systems. It is usually called an Edit Decision List (EDL) when it is used in video

4 editing systems. Q-Sheet can record the following types of MIDI events: Note on/off, Control Change, Program Change, Polyphonic Pressure, Channel Pressure, Pitch Bend, Channel Mode, and System Exclusive. These in turn can be used to communicate with the various MIDI devices to be found in a wellequipped Midi/Audio/Video Post-Production Studio. Q-Sheet Control Window Q-Sheet Audio Meters Midi/Audio/Video Post-Production Set-up: The aim of such a system is to allow you to have a near-total degree of recall of the complete studio setup so that you can work on a particular piece one day, and come back to it at some point in the future and automatically recall all the data for all the MIDI devices. This may include the automated faders & mutes on a MIDI-controllable mixing desk, DMP7/11 submixes and setup, the synthesizer voices, the samples and sampler setups, the reverb, delay, and studio effects programs and the MIDI music and event sequences, as well as any digital audio recordings on disk. During a session all the appropriate data may be stored via MIDI system exclusive messages into either a MIDI sequencer or directly into Q-Sheet. At the end of a session all this data can be stored onto backup media and filed away until the next time it is needed. A large MIDI patchbay is needed with such a system, because all the MIDI Ins and MIDI Outs on every device must be connected to the software in order for this automatic loading of the complete system to take place. To record data from several MIDI devices at once you will need several MIDI merge processors - for instance, if you wish to have more than one MIDI musician

5 playing at once, or if you wish to record more than one device's MIDI Automation moves at once. The MotU MIDI Time Piece would be ideal for this, with its 8 merge-able and separately addressable MIDI Ins and Outs, and its various expandability options. Unfortunately, Q-Sheet does not support the MTP's 8 separate MIDI data streams as yet, although you can have two separate MIDI data streams by using both Printer and Modem ports from your Macintosh with the MTP. Yamaha, Roland, ART, Drawmer, and others manufacture various MIDIcontrollable Studio effects processors including various types of EQ, compressors, and so on - which can be controlled directly via Q-Sheet. There are also many MIDI mixing console fader/mute systems available, with more becoming available every few months. Templates containing on-screen controller interfaces (called Automation Windows) for a couple of such devices and for the Yamaha DMP7 MIDI-controllable mixer are supplied with Q-Sheet. However, it is relatively easy to create your own Automation Window for any MIDI mixer, assigning MIDI control numbers to the appropriate parameters of the MIDI device so that you may control it from a window on the Mac. You are provided with a selection box containing a fader, a rotary control, a push-button switch, and a counter, and you can just drag as many copies of these as you wish onto the active part of the screen and adjust their sizes to get the layout you require. Q-Sheet Syncing: Q-Sheet has an internal timer that allows the program to synchronize to its own internal clock, and you can just use this internal clock if you just want to use the program to automate your MIDI set-up without syncing to SMPTE. Normally, however, you will be synchronizing to external clock via MTC. This proved to be a very 'painless' operation on the 'Thomas' sessions, using a MotU Video Time Piece to read VITC from the U-Matic and converting this to MTC - which was then sent to a MIDI Time Piece for input to the Q-Sheet software on the Macintosh. Everything locked up quickly and easily the first time I ran a videocassette, with no problems at all. Quite often I forgot that it was synced up and was surprised to see the display registering as I ran the video to spot some effects - it was that 'transparent' to me as a user of the system! Q-Sheet Windows: There are two versions of the Control Window, one for syncing to MTC and another for syncing to the internal clock. Both display SMPTE time and Record, and the internal clock window has controls for play and stop as well. When syncing to MTC, Play and Stop are controlled from the tape/ video recorder via the SMPTE/ MTC synchronizer. The main window is the Track Window which allows you to record, overdub, play, or mute any track, auto punch-in/out on a track, set the MIDI channel and the output port and any SMPTE offset you may require, name the tracks, and arrange the order of the tracks in the list. In addition, each track has a Controller or Automation Window Icon, which will display on-screen animated controls assigned to various MIDI Controllers when you click on it

6 with the mouse. This is where you may construct your own on-screen interface for virtually any MIDI device. Q-Sheet Tracks Window There is a Cue List Icon for each track, which you can click on to display the track's Cue List Window containing a list of all the events stored on the track. In the 'Thomas' series, we used a separate track for each engine and its associated effects, and one for the general effects. These tracks mostly consisted of lists of MIDI Note Numbers, which I entered by hand, and which were used to fire the samples from the S1000. A track can alternatively be configured to accept a cue list of Sound Designer II digital audio files. This is where we set the cue points for the dialogue and the music to be played back from hard disk via Sound Tools. Q-Sheet MIDI Track/Cue List (Also showing automation data)

7 In the upper left hand corner of the track window there is a Master Cue List Icon that will allow you to display all the events from all the tracks combined into one master list, (but will not allow you to edit these events; you must do this in the appropriate individual track). This Master Cue List lets you see an overview of all the cues, which you may have split up onto different tracks for operational convenience. There is also a Print option under the File Menu, which will let you print out copies of any of these Cue Lists, Automation Windows, or Track Windows for use during your session. Q-Sheet Automation Window Q-Sheet Automation control dialog box Tracks: There are two types of tracks in Q-Sheet - Audio and MIDI. The MIDI tracks let you record MIDI Note Numbers, Controller information, Patch Changes,

8 and so forth, and you use these to control your samplers, synthesizers, and MIDI-controllable effects units. Each track may be offset individually, and both incoming and outgoing MIDI data may be filtered to block either recording or playback of specified MIDI messages. Each track has a "Chase Delay" function to delay transmission of MIDI for a specified time period after a program change message is transmitted. When you start Q-Sheet from the middle of a cue list, the program will automatically chase all MIDI Program and Control Change events that occur before the playback start point, thereby setting all MIDI devices to the correct state that they should be in at that point in the proceedings. However, some MIDI devices don't respond to MIDI while changing programs, so you may need to set a time a delay before sending any more MIDI messages to such devices. Typically, this delay could be as much as one second, and entering a chase delay will enable you to get around this problem. The audio tracks let you replay mono or stereo audio files in Sound Designer format from your hard disk - if you have the Sound Tools 'Audio Accelerator' board installed in your Mac. You can even use Q-Sheet to record audio directly and save it to hard disk as Sound Designer format files - if you have a Sound Tools 'AD In' or 'DAT I/O' unit. Music Sequences: If you are using your Macintosh to run MIDI Sequencer software to record your Music sequences, you may be wondering how you can also run Q-Sheet to handle the MIDI Automation and Cue List if you only have one Mac. One solution might be to run both the sequencer and Q-Sheet under Multifinder using the MIDI Manager software to let both programs communicate with each other and with the outside world. This is still asking the Macintosh to do perhaps too much processing, though, especially on the slower models. However, you can save files from most MIDI sequencers as MIDI files. Such a sequence file can then be loaded into Q-Sheet and assigned a SMPTE start time, initial tempo, chase delay, and serial port. If you are using a stand-alone MIDI sequencer or drum-machine that does not support the MIDI file format, you can play such a sequence into Q-Sheet's Capture Sequence function and save it as a MIDI file. So in practice you can run any MIDI sequence from Q- Sheet one way or another. Conclusions: Q-Sheet is an extremely well designed and well thought-out piece of software, and proved to be 100% stable in use. Although you could use a fullfeatured MIDI sequencer with digital audio capabilities (such as Digital Performer or Studio Vision) to do pretty much the same things, I found Q- Sheet's user-interface to be eminently suited to the tasks I needed to carry out while putting audio to picture on the 'Thomas' series. I wish Digidesign would add MTP-compatibility, as well as full sync to other MIDI software running under Multifinder via the MIDI Manager! One of the main advantages to using this system over conventional multitrack tape recorder techniques was the ability to quickly swap sound effects or adjust the timings of the cues in the EDL. The Akai sampler proved to be

9 quite suited to the task, although I would have liked to be able to program it from the Macintosh using the new software, which I have heard is now available from Akai. Better still, I would have liked to use a Samplecell card with 32Mb of RAM! As we were working in Mono, the two tracks of digital audio via Sound Tools proved adequate for the mono vocal and music tracks, although we had to use a sampler for the sound effects. For working in stereo, at least four tracks, if not eight or more, would be required. The new Pro Tools multi-track system from Digidesign should be available by the time this article is in print, and this should provide the perfect low-cost system for putting stereo audio to picture, which will be more commonly required for future TV/Video projects. Equipment Used: Q-Sheet A/V version 2.01 Sound Designer II version 2.0 Dat I/O, AD In, Sound Accelerator card. Macintosh II with 8Mb RAM, internal 40Mb hard disk. DAC 780 Mb external hard disk. PLI/Syquest 45MB removable hard disk drive. Sony DTC1000 DAT recorder with HHB 44.1kHz modification. Akai S1000PB sampler with 20 Mb RAM, and a DAC 200Mb external hard disk. DX7IIfd synthesizer. Macintosh Computer: For serious professional use you really need an SE30 or a Mac II with at least 4 (and preferably 8 or more) Megabytes of onboard RAM and a 780 Megabyte Hard Disk. You need the extra RAM because part of the Q-Sheet program is loaded into RAM when you boot the program, and you may well wish to have other programs (such as Sound Designer II, or Performer) running under MultiFinder or the new System 7. Also, to hear audio loops in Sound Designer II, they must be able to fit into RAM, so you can easily use up your RAM. The longest samples I looped were about 7 seconds, and these fitted within the 8Mb of RAM installed in my Mac II, as long as I ran under the Finder. You will need to use a 780Mb hard disk (which formats to about 650Mb) to give you enough space to store up to an hour of stereo audio. MIDI Interface: You will need a suitable MIDI Interface, preferably one which will allow you to use both the Printer and Modem ports on the Mac, such as the Opcode Studio Plus or the MotU MTP which actually has 8 separately-addressable and mergeable MIDI ins/outs and a SMPTE/MIDI converter as well, although you cannot address these individually from Q-Sheet as yet. If you wish to run Q-Sheet while syncing to time code and simultaneously record MIDI data in from a keyboard or other MIDI device, you must either connect the time code to one of the Mac's serial ports and the keyboard to the other Macintosh serial port, or you must merge both sets of data through one port. This can lead to problems because of the nature of the MTC messages, so it is best to avoid merging the inputs by using 2 MIDI interfaces or a double interface like the ones previously mentioned.

10 Synchronization: Q-Sheet synchronizes events to MIDI Time Code. MIDI Time Code must be sent to the Mac from a SMPTE/MTC converter, such as the Mark of the Unicorn MIDI Time Piece MIDI Interface for the Mac, or the Opcode Studio 3+ SMPTE/MIDI converter, or from a unit such as the JL Cooper PPS1. SMPTE stores an exact time reading on the tape 24, 25, 29.97, or 30 times a second corresponding to the appropriate Frame rate in use. So a particular sound effect or MIDI event can be initiated at a precise Frame location. For instance, a gunshot sound effect can be played at the exact instant the gun's flash appears on-screen, a fader level can be increased the moment a guitar solo starts, or a digital reverb can decrease the "size" of a simulated room as an on-screen actor walks from a large room to a smaller one. MIDI Time Code (MTC): It is not practical to transmit actual SMPTE Time Code over MIDI because each SMPTE message (one frame) is composed of 80 digital bits. Transferring this much information over MIDI24-30 times a second would use up too much of Midi's limited bandwidth, and would compete for available bandwidth with normal MIDI messages, possibly causing delays. As it turns out, full SMPTE Time Code is only necessary for synchronizing the transports of tape recorders. For triggering MIDI events and automating MIDI devices, MTC transmits SMPTE time code locations over MIDI every quarter frame. There are 4 messages per frame, each 2 bytes long, and 8 quarter frame messages (ie 2 frames) are needed to definitely establish the SMPTE time. Once a receiver has received 8 messages and has assembled a valid time, it can keep counting internally and just use the new messages to track fluctuations in the tape speed and the like. If necessary, the receiver can also interpolate finer times between the messages to keep up accurately and place such things as tempo clocks. At 30 fps a 2-byte message (640 microseconds long) is sent every 8.33 milliseconds (every 1/4 frame). This takes 7.68% of the MIDI bandwidth, a reasonably small amount. It is still better to keep the MTC and normal MIDI data streams separate because problems can occur if you try to merge MTC, and normally you would find that there is no need to send both to the same device, so this is not a problem. The MIDI Time Code spec also includes a standard format for transferring "cue lists" between MIDI devices that have internal cue list capabilities. LTC & VITC: There are two types of time code that Q-Sheet can use, Longitudinal Time Code (LTC) and Vertical Interval Time Code (VITC) [pronounced vitsee]. LTC is recorded as an audio signal on one of the tracks on the audio or videotape. VITC is recorded between the video frames of the video signal. Obviously, VITC cannot be recorded onto audio tracks. Each type has advantages and disadvantages: LTC can be read at up to 50 times play speed so everything will stay in sync when the tape machines are in fast forward or rewind, but minimum speed is about 1/10 normal play speed, so the SMPTE time cannot be read when the VCR or VTR is "crawling" or stopped. With VITC it is the other way round; it can be used when "crawling" or stopped,

11 but maximum speed cannot exceed about 10 times play speed, so it cannot maintain sync in fast forward or rewind. Using VITC in practice on 'Thomas', I found that if I stopped the VCR playing and captured a SMPTE time, this worked perfectly. However, if I used fast wind and then stopped and used capture, the wrong location would come up. Frame-Lock: When working to time code coming from an audio track of a VCR, each frame on this time code must correspond to the correct frame on the video. So when striping the audio track with SMPTE code, this code must be referenced to the video signal from the VCR itself, or both must be referenced to a "house code" video frame sync generator. This is known as 'Genlocking'. Professional Time Code Generators from Adams-Smith and similar manufacturers allow you to do this. I used Mark of the Unicorn's Video Time Piece which also includes a genlock facility, although the supplied U-Matic came with genlocked LTC on one of the audio tracks, as well as genlocked VITC, so I did not need to stripe the video myself anyway. Most currently available SMPTE/MIDI converters with time code generators included in the unit do not allow you to do this. If you stripe your VCR audio track and your MTR and ATR tracks with SMPTE from a device such as a Roland SBX80, C-Lab Unitor, FriendChip SRC, or even an SSL Mixing Console - without Genlocking - you will have the illusion of frame accurate sync-to-picture, only to find that the audio and video won't lock up correctly at layback (because the SMPTE code on the audio tracks is not locked to the video frames). So don't forget, always stripe all your audio tracks from a SMPTE Generator, which is frame-locked to the video which you wish to synchronise with! Mike Collins August 1991