In Beebug Vol. 4 No. 1, we looked at the Island Logic Music System, the Clef Computer Music System, ATPL's Symphony Keyboard and Acorn's (or Hybrid's) Music 500. Since then, new utilities and Song and Sound Library discs have been produced for The Music System and two MIDI interfaces have appeared too; not to mention Beebugsoft's own MUROM and Studio 8. Here we will see what The Music System extras and MIDI has to offer the budding Beeb musician.

System, 12 Collegiate Crescent, Sheffield, S10 2BA. 0742-68321.

The Music System (TMS) at £29.95 is undoubtedly a most sophisticated music editor. The program comes supplied with a Song and Sound Library containing examples of songs and sounds (what else?) which you can use yourself in the program. Five other Song and Sound discs have been produced by independent programmers and these are available at £4 each. They include, Toccata and Carols, 400 Years of Music, Mainly Bach, Ian Waugh Originals and O1d Favourites. (Yes, that's me. Well, I thought the program so good that I wrote some pieces for it).

System has also released a Utilities Disc at £6 which includes a program to play TMS files from Basic. The Music System uses different envelopes and music protocol to the Beeb, so this is not easy.

Before it can be attempted the TMS file must run through a converter. Every envelope and amplitude may not be converted exactly and the tempo may need adjusting. The noise channel is not converted at all, nor can it handle certain notes, but it tells you which ones so you can alter them. In spite of this, the ability to play tunes in your own Basic programs will appeal to many users.

There is also a utility to convert a keyboard file to a music file. Again, it does not promise to convert it exactly but it does the best it can. A third converter is for owners of System's Music Editor, the forerunner to The Music System, and this converts ME files to TMS files.

The Utilities and Song and Sound discs are only available on disc from System by mail order (or at computer shows).

Electromusic Research, 14 Mount Close, Wickford, Essex, SS11 8HG. 0702-335747.

On to something a little heavier now - MIDI - and a few words of explanation for anyone to whom this is unfamiliar. MIDI is an acronym for Musical Instrument Digital Interface and was developed to allow different electronic instruments to communicate with each other. Typically, one synthesizer can be used to control others in synchronization with a sequencer and drum machine.

As MIDI uses digital signals it is a prime target for computer control. A MIDI interface bridges the hardware gap between the computer and external instruments and the software allows you to compose a piece and play it back on one or more instruments. There are 16 MIDI channels three other packages and updated the original. They fall under the general title of Miditrack and include the Performer (£49.95), the Composer (£44.95), the Music Editor (£39.95) and Vu-Music (£24.95). EMR's MIDI interface itself costs £79.90.

There are two ways to put music into a MIDI system: real-time and step-time. Real-time music is recorded from a keyboard 'live'. Step-time music is entered one note at a time from a music keyboard or from the computer. Although real-time is great if you are an accurate player, step-time lets you program pieces which are impossible to play, and with 100% accuracy. The Performer is a real-time system and the two demo programs on the disc - an excerpt from the fourth movement of Beethoven's Sonata in C minor and some jazzed-up Christmas carols - show what can be achieved.

You can record on up to eight tracks, working in a similar way to recording on an eight track tape recorder, but you can transpose a track up or down 12 semitones and cause it to loop continuously. Performance information, such as pitch bend, can be recorded too. A polyphonic and mono mode allows you to use multi-timbral instruments (which can sound more than one voice at the same time) such as Casio's CZ-101 and CZ-1000@. These are a cheap and effective way of using MIDI's multi-tracking ability. Unfortunately, the metronome sends its 'tick' through channel 1 which affected the Casio when in multi-timbral mode. A tick through the Beeb's speaker would have been better.

You can create 64 arrangements of the recorded tracks and an auto note-correct feature (often called 'quantization') will correct any small timing mistakes you may make. By routing the output to the input you can also merge tracks.

The Performer is reasonably easy to use in spite of its wealth of facilities, but it does take a while to get to grips with and the program crashed once in the process. The only editing facility is a punch-in system but the Music Editor was designed for that purpose.

The Composer is menu-driven and gives you six tracks to record on. You can allocate MIDI channel numbers to the tracks and set Mono or Polyphonic mode. Multi-timbral instruments perform superbly.

Notes can be entered from an instrument or the computer. They are shown as a series of numbers representing such parameters as pitch, duration and volume. It can be more difficult to read than traditional notation but it has advantages and it soon becomes familiar. You can insert and delete notes and rests, alter the voices, change dynamics and add modulation control. A function key strip helps. You can also copy sections to other tracks with optional transposition.

The Music Editor complements - the Performer and the Composer. It converts Composer files to Performer files and allows full editing of a polyphonic track. Each byte of MIDI information is shown and you cannot get much further into the system than that. Full editing is therefore possible, once you have come to grips with the numeric notation. Demos are included for you to sift through and learn from. Such delvings are not for the faint-hearted but they do improve your ultimate control over compositions.

Files can be linked for continuous playback and free memory has been increased by 50% over the Performer program. Another program called Music Player loads and plays Performer files.

Vu-Music produces a graphic display which varies according to the music played. Input is only in real-time via a MIDI keyboard and you cannot play pre-recorded pieces, which is a pity.

EMR are also working on The Notator which should retail for £34.95. This will print out a track from the Composer in traditional music notation.

For MIDI software, these programs are cheap and they offer a lot of facilities not always found in MIDI packages. They may take a little getting used to, but as your music system grows, it should keep pace with you.

The London Rock Shop, 26 Chalk Farm Road, London, NW1 8AG. 01-267 7851.

From one end of the MIDI interface spectrum to the other - the UMI-2B retails for £495. It is probably the most expensive MIDI interface system on the market even though you get the hardware interface and software (on EPROM) for your money.

The box has enough plugs and sockets to ensure compatibility with just about anything. Note entry is really geared to real-time but it does have a step-time facility too. The program is menu driven from a series of mode 7 screens.

Recording is as simple as pressing a button and playing some notes. The sequence will automatically play back so you can develop other lines to go with it. It is really the ideal tool for the songwriter or jingle writer and many professionals are already using it.

Each sequence you record is called a pattern and up to four will play back on auto replay. Patterns can be linked together to form a song and saved to disc together with a notes page onto which you can enter details of the recording.

The program remembers all modulation controls and, as these use a lot of memory, a pack function will reduce them bit by bit until they nearly disappear. If you go too far, all is not lost as you can call up the original setting again. There is also an auto note correction facility and, as with 'pack', you can return to the original, too.

Step-time and real-time note entry can and instruments can be instructed to send or receive information on any channel.

To produce MIDI music with your Beeb you will need a MIDI interface, a synthesizer, or other instrument with MIDI connections, and suitable software. Most of this turns your MIDI/micro system into a super sequencer or a digital tape recorder - only better, as pieces can be speeded up, slowed down, and individual notes and phrases very easily edited with no loss of timing or signal quality.

EMR have produced more MIDI packages for computers than any other company and the BBC micro ranks high on their list; in fact they were the first to produce a MIDI package for the Beeb. That was almost two years ago and they have since produced be combined so you can enter difficult sequences easily. The program also includes a patch and bank dump for Yamaha's DX7 synth.

This is really a professional package aimed squarely at the professional musician, not the computer buff. It has, unfortunately, a professional price tag to match, but if you can afford it, it is a very useful piece of equipment.

Music, and MIDI-controlled music especially, is a complex subject at the best of times. However, a micro can do much to alleviate this and change the skills needed of a musician from pure technique to a more artistic bias. Indeed, you can now have next to no technical skills at all and still produce good music. With the products I have looked at here, owners of a BBC micro will find help on this score at all levels.