Lizzy reviews Electromusic Research's new BBC MIDITrack Composer and Interface Unit.

ElectroMusic Research is run by Mike Beecher, ex-editor of Electronics & Music Maker, which suggests that Mike is putting his early knowledge of MIDI to good use. The package presented for review consists of the usual UART (Universal Asynchronous Receiver/Transmitter) MIDI hardware, familiar to all who have jerry-built their own from magazine plans(?), designed for connection to BBC B computers. The MIDITrack Composer is supplied on tape or disk and allows the purchaser to step input music parameters from the computer for composition on six monophonic tracks, suitable for reproduction on all MIDI equipped instruments. All this is offered at £152 inc. VAT with the comforting reassurance that the software supplied is merely introductory and that further, more interesting, software packages will be available shortly at extra cost.

Hardware

There is little point in going into circuit level descriptions as MIDI facilities are standard so from the outside of the hobbyist-type project box, clockwise from the top left, are 5-pin DIN Clock Start/Stop, suitable for connection to Roland sequencers and drum machines etc. (Sync Out/In usually), MIDI In, MIDI Out 1, MIDI Out 2, 34-way ribbon cable connector to BBC 1 mHz Bus and 20-way ribbon connector to BBC User Port. On the front of the box are two LEDs, a red one that lights when MIDI data is output and a green one for MIDI data input (the supplied software cannot deal with data input so this and MIDI In are for future developments). Also supplied is a function key chart that slips under the clear plastic strip above the ten BBC function keys indicating the parameters assigned to keys during composition, like so:

Software

On loading the operating program from disk or tape you are invited to specify the MIDI configuration you require by stepping through five menu pages, as follows:

Page 1 — Track Assignment — Default 1 .Allows you to select the maximum number of tracks (1 - 6) needed for the piece to be composed or performed. This divides the available RAM between the set number of tracks so that, for example, selecting one track allows 6,900 events on that track and selecting six tracks allows 1,150 events per track (an event is any single MIDI instruction which can be a note, a rest, a performance/modulation control command or a voice change). All this seems fair enough but if, part-way through a composition, you find you need more notes and less tracks or vice versa — you're stuck! There is no facility to re-configure the MIDI information already entered so if you want to change it you have to start again. Also, it is likely that one or two synth parts, say — a twiddly fill or a bass line, will only require a small percentage of the available events on a track, wasting the unused memory. Because of this it's easy to run out of events on a fairly simple arrangement using all six tracks. It is eminently possible to organise the software so that memory allocation is automatic and flexible, making track memory assignment unnecessary — unless you're cutting corners.

Page 2 - MIDI Channel Mode — default Omni on, Poly on. Selects combinations of Omni on/off and Poly/Mono modes for the MIDI instrument receiving.

Page 3 — Track To Channel Allocation — default channel 1. Any track can be assigned to any of the 16 available MIDI channels. All six tracks can be assigned to a single channel, giving full six note Polyphony, or they can be assigned to six separate channels giving six monophonic parts, or any track combination of 2 & 4, 2, 1 & 3, 1,1,2,1, etc.,etc.

Page 4 - Synchronisation — default Internal. Selects the system timing as internal, derived from the computer under software control (see Main Menu — (5)), or external from a sequencer or drum machine into Clock Start/Stop. In addition, the internal clock can be used to drive MIDI equipped sequencers and drum machines from one of the MIDI outs.

Page 5 — Main Menu. This is the most used page during composition and consists of eight options thus:

(1) Catalogue — lists files contained on disk or tape.

(2) Load Music — from disk or tape, by name.

(3) Save Music — to tape or disk, by name. All current MIDI info stored.

(4) Create MIDITrack — on confirmation of an "Are you sure?" prompt the current composition is cleared from memory and option (5) is actioned (see below).

(5) MIDITrack Composer — this is the guts of the program where all event data is input. Selecting five calls the composition page which lays out event parameter titles in reverse field at the bottom of the screen, like so:

Event data is input by pressing the 'space' bar before entering each parameter or editing command. With reference, in brackets, to the example data line above, the order of input is:

Track — Any track number up to the maximum assigned on page 1,(1).

Event — Allocated automatically as the next available event on the specified track.

Value — Note data is entered direct in the format - Note letter (G) — sharp or flat, if required (#) — octave, 0-7 (3). Middle 'C' is usually C3.

Further Value options are:

'V' then enter preset voice number required, 0-127.

'M' then modulation or performance control codes, range 0-127.

'R' for rest, select rest length in 96ths of a note from function keys, 3-96.

'/' ends event data input for the current track.

Dynam — Enter the required relative volume of the note, ppp-fff, from the function keys (f). Only relevant for instruments capable of touch sensitivity.

Length — selects the length of a note event using function keys. 3/96ths to 96/96ths of a note relative to the Tempo set (24).

Style — Selects the style of note played by varying the Gate On time. Options — 1 Tie, 2 Staccato, 3 Legato and 4 Pulse, from function keys (2).

As each line of track and event data is completed the screen Scrolls upward, with lines disappearing from the top as the screen fills.

While in MIDITrack Composer there are nine further editing commands available:

(I) Insert event in given track.

(D) Delete one or more events from given track.

(R) Replace event in given track.

(C) Copy one or more events from track to track

(L) List a sequence of events on a given track— (H) outputs the listed events to the instrument for audible reference.

(B) Prints a beat/bar count that tells you the number of notes and rests between two given events.

(T) Displays current tempo and enables you to vary playback clock speed from 35-8784 (96 clocks equivalent to one whole note).

(P) Sets MIDITrack Composer to playback. 1-254 repeats can be set or (I) sets infinite repeats. During playback a clock counter is displayed on screen and tempo can be continuously varied using the "<' key for slower, '>' key for faster.

(Q) Return to Main Menu

(6) Memory Free — displays free events available on each track.

(7) Select Play Tracks — sets tracks to be heard on playback.

(Q) MIDI Configuration — returns the program to Page 1.

"EMR seem to have taken a great deal of trouble over providing most MIDI control features without thinking too much about the poor musician who has to struggle with them."

Composition

The complexity of the composer software is pretty daunting and despite assurances from EMR that, with a little practice, "you'll find yourself virtually 'typing' the music onto the TV screen" I think it will cause problems among prospective Beeb MIDI musicians. Grasping the principle of inputting single track events is okay, assuming that you're all about on music notation, but juggling a number of tracks/events to produce chords etc, makes the brain hurt and you have to resort to much scribbling to work out timings, note parameters and rests. A good pointer to the likely hassles is that it takes 16 procedure steps just to play one of the unimpressive example pieces supplied! Well, at least it all works.

Judging by comments from Rose Morris staff, and the play I had with it, a great deal of practice is necessary before all the editing procedures fix themselves in your mind. A major problem in keeping account of things is that you can't list timing interrelations between tracks to see where chords etc, should occur as notes that sound together probably won't share the same event numbers. This means that either you have to laboriously write out each event for all tracks before you start or struggle along by trial and error listening to a small chunk of the composition at a time — a method that leads to much confusion as, even after a mere dozen events, what you've composed nearly always turns out to be nothing like what you intended.

Bearing in mind the gnashing of teeth and banging of heads that's likely during composition it's terrifying to discover that if you accidentally press the 'Break' key, all current MIDI data is lost! I know you can save part-written pieces for security but it is ridiculous that the 'Break' key isn't disabled from within the program.

Conclusion

EMR seem to have taken a deal of trouble over providing most MIDI control features without thinking too much about the poor musician who has to struggle with them. It is very difficult to make a step input only composer easy to use but just allocating editing features to different combinations of single keys is not the answer. Less menu pages, intelligent use of graphics and selection of parameters by cursor is preferable. Even better would be a combination of real time input from the instruments with editing/step time modification from the computer. This would be a boon to non-music literate musicians (like most of us) and much, much easier to use.

Disregarding the unfriendliness of the software it is strange that no real polyphonic facilities are supplied. MIDI is capable of unlimited polyphony on all 16 channels. While it is unrealistic to expect full implementation with the limitations of processing time and free memory, the optimal arrangement is eight polyphonic tracks. This does require some sophisticated machine code programming but the provision of just six mono tracks suggests software short cuts.

All in all it seems that, along with everyone else, EMR put the MIDITrack Composer together in a hurry so they could be first on the scene with Beeb MIDI product. Ten out of 10 for speed. Two out of 10 for programming. I'd wait until they provide more sensible software or look elsewhere.