David Mellor does the impossible and reviews a product that does not exist! Perhaps one day it might, but for now this 'ideal' MIDI sequencer program lives only in the imagination of the author.

Am I unusual, or just plain unusual? My trouble is that I can never find a MIDI sequencer that really suits me. There are plenty on the market with interesting capabilities, but I have yet to find one that really makes me go weak at the knees.

It's different with other pieces of equipment (can you call software equipment?). I can get my hands on a new synth and think 'Wow! This has got a lot of good features!' and get on using them straight away. Sequencers are more awkward. I can't seem to get hold of all the features I want in one package. At the moment I use a Hybrid Arts SMPTEtrack, which I am extremely pleased with. It has two very important features that I must have - the facility to define sections right down to 384th note accuracy (some sequencers only work in whole bars) after recording them, and an integrated tape sync box. I use tempo changes a lot in my music, and if you don't have communication between sequencer and sync box, you have to enter tempo changes into the box rather than into the sequencer where they belong, which is inconvenient.

Something that seems puzzling to me is why computer-based sequencers seem to want to work in 'numbers' so much. If you use one already, you must know the feeling where there is a wrong note somewhere in a lengthy MIDI event list, if only you could find it! With a computer screen, there is the perfect opportunity to link sound with vision - that is vision in the form of graphics. Words and numbers can only get in the way. What is needed is a way of linking the music that you are creating to a graphic display which shows you what is happening and where. Some highly trained musicians can look at a musical score and 'hear' the music; nobody can look at an event list and get any music out of it, I'm sure of that. There has to be a way where the structure of a piece can be seen and appreciated, for trained and untrained musicians. This is the principal feature I have tried to achieve in my as yet non-existent MIDI sequencer, Imagination.

DESIGN

The first thing I have to say is that I don't know the first thing about computers. Actually, I did write a computer dating program when I was at school, but that got me into so much trouble I didn't care to repeat the experience! What I do know about is what I want from a MIDI sequencer - always hoping that other people will find it to their liking too. What I have done is to work out in as much detail as I can how Imagination will appear to the user. A programmer would have to sort out the internals, and probably tell me that I am asking for the impossible in a few cases. There would have to be dialogue between musician and programmer to achieve an end result that was acceptable to all.

Most sequencers are based on the concept of tracks and sections. A 'track' is analogous to a tape track; a 'section' is a verse or a chorus of a song which you can string together to form a complete piece of music. Imagination has neither tracks nor sections - at least, not as they are conventionally known. Instead of tracks, Imagination has 'Instruments'. Hopefully, there would be at least 60 of them, but that would be up to the capabilities of the computer and the programmer. Each Instrument represents one program on a MIDI synth. On a conventional sequencer you would assign your DX7, say, to Track 1. Track 1 would then record everything you played, and also any program change messages received. In this way, Track 1 could be skipping around from Electric Piano, to Strings, to Marimba or anything else. Imagination will only let you place one sound on one track - which is why Imagination's 'tracks' are called Instruments. If you need to change programs, then a new Instrument will be allocated and you will be invited to supply Program Change instructions (by pressing the buttons on your synth of course, not on the computer keyboard). As you can see from Figure 1, both Saxophone and Flute share MIDI channel 15. The same synth would play both, and Imagination would output MIDI Program Change messages at the appropriate time.

The advantage of doing it this way is that if the sounds have different attack times, you can shift each Instrument forwards and backwards in time independently to compensate and bring them in line with the rhythm track. If everything was together on one track, this would be more difficult. I also think it gives you a better idea of the orchestration of the piece.

To compensate for the small number of Instruments that Imagination can display on screen at any one time, there is also a display of the 'Orchestra'. When any Instrument is active, this will show up in the Orchestra display, even if that Instrument is off the screen. Editing can be done locally on the Instruments and globally on the Orchestra, as I shall explain.

There are no 'sections' in Imagination, not as we usually know them anyway. It is possible to define the screen into sections, and you will see that the example in Figure 1 is marked 'Intro', 'Verse 1', 'Chorus' etc. This is purely for the composer to find his or her way round. Imagination runs linearly from beginning to end. There is a cursor which tracks across the screen in time with the music, or in correspondence with the movements of the mouse.

To construct a song from parts, we use the concept of the 'Fragment'. All editing operations in Imagination are performed on a Fragment of an Instrumental or Orchestral part. There can be one marked Fragment at any time. This Fragment can be quantised, transposed, punched-in upon, or it can be copied or moved to another location. Since a Fragment can be marked in the Orchestra, you can copy a whole verse to a new location in a song and build the piece up that way. Why, you may ask, is this better than working in sections?

- With separate sections, it is hard to hear how a verse and chorus will join together. Imagination lets you hear the passage you are working on, and also the run up to it, if you wish.

- Timing. You can't sensibly run a MIDI sequencer using quantisation unless you can slip tracks back and forth against each other to compensate for their attack times. If you do this on a section-by-section basis, you find that the first note of a section can often be time-shifted to before that section is meant to start! The result is that it is either lost, or appears on the first beat of the section - which, of course, is out of time because it doesn't account for the time shift you had programmed.

- Versatility. If you work in sections, your music will sound like it was written in sections. With Imagination, you can do this if you want, but you also have the option of composing in a less 'regimented' manner.

EXERCISING IMAGINATION

This is how you do it. Suppose you have just started on a new piece of music - and by the way, in Imagination that is called a Piece, not a Song; I haven't heard a sequencer sing yet! Let's lay down a few Instruments...

To get started, you need to activate an Instrument. You do this by pointing the mouse at the space where the Instrument's name will appear and clicking the left-hand button. The name space for the Instrument will then go into reverse video (white on black), and you will be asked to supply a name and MIDI channel before you proceed. No un-named tracks allowed here!

Having done the housekeeping, click on the RECORD button and you will be given a count-in. The count-in corresponds to the pre-roll time you have set from the Options menu. More on this later. Record for as long as you like, and click the right-hand mouse button to stop. (The right-hand button always stops Imagination). To hear what you have done, click on PLAY. If everything's recorded alright, repeat the procedure with another Instrument. After a while you will have something that looks like Figure 1.

Now we shall do a spot of editing. To edit, we need to mark a Fragment. First, the appropriate Instrument is activated, in this case the Piano on MIDI channel 1.

Click the Fragment button (second down on the left). Moving the mouse horizontally will scroll through what you have recorded. If the mouse pointer is in the display area of the screen, where Instrument activity is shown, you will hear the music scrolling through, keeping pace with your mouse movements. If the pointer is out of this area, all will be silent. By scrubbing the mouse backwards and forwards, like editing tape, you can home in on the point you want to be the beginning of the Fragment. A glance at the counter will help you get spot on the right beat. Click the mouse and the Fragment start is marked. The end is marked in the same way. If you want to hear the Fragment to satisfy yourself that all is OK, click on AUDITION and you will hear it (just the active Instrument). As the Fragment has not yet been edited, you will hear it without pre-roll. If you wanted to hear the Fragment with all the Instruments playing, click on AUD. ORCH, which auditions the Orchestra.

To perform any editing operation, click on the appropriate button, eg. QUANTISE. A dialogue box will then open on the screen asking you whether you want 8th notes, 16th notes or whatever, together with an EXECUTE button. Once again, the AUDITION button will let you hear what you have done, this time with pre-roll and post-roll (remember that the times for these have been set from the Options menu). If it's not right, the UNDO button will return you to the point before the last editing operation. For now, let's assume that all is well and continue with the recording.

This time, you might not want to go from the start of the Piece. You might want to add a touch of Flute to the chorus, for example. This brings in the concept of the 'Marker'. The Marker is pretty versatile, and is set using the MARKER button in a similar way to how the Fragment start and end points are set. Used while recording, the Marker gives you the start point of the recording. If the Flute is to start on bar 32, then set the marker to bar 32, click RECORD and you will get a pre-roll, then you're off.

The Marker also facilitates editing operations. Suppose you had marked a Fragment and you wanted to copy it to another part of the Piece. The copy is made so that it starts at the Marker position. The same goes for moving a Fragment.

NO EVENT LIST?

There is no MIDI event list used in Imagination. Shock horror, headlines in the tabloids! Do you need an event list when you play live with your band? Do you need one when you record conventionally to multitrack tape? Well you don't need one in a MIDI sequencer either.

Event editing in Imagination is all done from the MIDI keyboard while listening to the music. There is no need for any numerical display of MIDI parameters.

The most obvious thing you might need to edit is the unavoidable wrong note. This is simple. You mark a Fragment and use the punch-in function to play the right note. Next come things like velocity editing, note duration and aftertouch. Here, Imagination uses the modulation and pitch bend controllers which any decent synth is proud of. Click on the EDIT button and a pop-up dialogue box asks you which parameter you wish to alter. Having done this, the music plays through and you enter the new data. The pitch bend wheel changes the data you have already according to how far you move it up or down; the modulation wheel erases the original data and replaces it with new data. Since you can set the Fragment to be as small as you like, you could accurately change the velocity of just one note if you wanted. The type of data you could change in this way could be anything except note number, even note duration.

To extend this idea, if you had a 16th note hi-hat pattern and wanted to accent the third note of each group of four, you could do this on one bar and then use the COPY DATA function to replicate this data right the way through the Piece. Specified data in the Fragment is copied to any other location in the Piece, to the same Instrument or to a different one.

Don't forget that clicking on the AUDITION button will let you hear the result of your edit straight away, and UNDO will get you back to your starting point if necessary. The separate panel lists many of Imagination's functions in more detail.

WISHFUL THINKING?

If this were a real review, at this point I would be asking 'How well does it perform in practice?'. Since Imagination doesn't actually exist, I don't know. There could be three potential problems. Firstly, I may not have thought out in sufficient detail the sequence of operations to make the thing workable. (I have thought a lot more about Imagination than I have written about it here, so I think it is mostly OK). Secondly, the programmer could come up with something slow and bug-infested. Thirdly, if Imagination did turn into reality, I might find that things don't work as smoothly as I anticipate.

Still, I believe there is a combination of features here that isn't found in other sequencers. It's the link between sight and sound that is important, and the jettisoning of excess numbers.

As a parting thought, any criticism of Imagination, from potential users or from the writers or distributors of current MIDI software, would be more than welcome. Perhaps Imagination can turn into a real product that incorporates the ideas of lots of people right from the start. Maybe one day...