One of the nice things about having specifications like the MIDI file format is that it frees you from having to use a single piece of software for the creation of your music. Since most software packages can read and write Standard MIDI Files, you can build up an arsenal of MIDI software that allows you to give free rein to your creative urges. You could (for instance) take the output of an algorithmic or stochastic composition tool like M, or your favourite fractal music generator, and import it into your sequencer for further manipulation. This method can also be used to obtain features that are not already included in your current sequencer without having to fork out extra cash for a more expensive piece of software.

COOL SHOES DRUMMER

One interesting piece of software in this vein is a package called Drummer from Cool Shoes Software in the US, which is essentially a drum programming page. If, like me, you use a track-based sequencer, you can sometimes miss the ability to play around with a pattern-based rhythm programmer. Drummer satisfies this need, allowing you to create up to 25 patterns of one to eight bars (which can have from one to eight beats). Each note in the pattern is displayed as a box on the pattern grid with the note velocity (ie. loudness) information being displayed as different shadings, the notes being set (or removed) by clicking the mouse on the appropriate box in the grid; dragging the mouse pointer creates longer notes, and you can edit a pattern in real time while it plays.

The patterns can be chained together on the score page to let you compile them into a longer piece, which can then be saved as a standard MIDI file, as well as in Drummer's native file format. Each line of the grid can be labelled with either the drum name or the MIDI note value and channel, and there are grid templates supplied for a number of popular drum machines. Of course you are not limited to using it to drive a drum machine and, since you can individually set the MIDI channel for each line of the grid, you could set up complicated multi-timbral patterns. The software uses its own peculiar GEM-like user interface (so you need a mouse) and can be run on any PC with at least a CGA video card and an MPU401-compatible interface; there is also a Yamaha C1 version available. Overall, Drummer is very useful piece of software — albeit with a few rough edges — and is very good value for money at US $99; it is available direct from Cool Shoes ((Contact Details)) or from CMS in the UK ((Contact Details)). You can download a demo of both the PC and C1 version of Drummer from the route66/progs area of CIX ((Contact Details) modem).

WINDOWS 3.1 — ALTERNATIVE SOUND DRIVERS

If you've upgraded to Windows 3.1 then you'll know that you can use digitised sound with both the operating system and MPC compliant applications. If you haven't bought, or don't want to buy, a sound card that supports digital audio, then there are a couple of low-cost alternatives. This makes a lot of sense if you already have a synthesizer card (like the Roland LAPC or SCC-1) or a MIDI interface and an external expander module that is already supported by Windows, since the cheaper MPC sound cards available at the moment can't compete with the Roland cards in terms of sound quality. The cheapest way of making your PC speak is to get hold of one of the public domain PC speaker drivers which can be downloaded from various bulletin boards. These drivers actually use the PC's internal speaker as a '1-bit' digital-to-analogue convertor! The sound quality is pretty awful, but it's amazing that it works at all. Unfortunately, the drivers take complete control over the PC whilst they are playing back the sound, which can be a fatal problem if the sound is being looped, as Windows will effectively 'lock up'. The two drivers I have seen are called SPEAK.EXE and SPEAKR.ZIP, both available from the windows/mmedia topic on CIX.

WAVE-PLAY RS

Another low-cost solution to getting sound from your PC is available from Speech International in their WAVE-Play RS unit. This is essentially an 8-bit DAC that fits onto one of the PC's parallel printer ports, and can replay mono digital audio at sample rates up to 44.1 kHz. The audio output is powerful enough to drive high impedance headphones (a set is supplied with the unit) but if you want to use speakers you will need to use a small amplifier. The unit comes bundled with various bits of software, to allow you to use the WAVE Play with either DOS or Windows, plus some 'sound clip' files. The unit is also compatible with games software from Electronic Arts. One of the advantages of this unit is that you don't need to have a spare expansion slot, although you do need to have a spare parallel printer port, since WAVE-Play can't share the port with a printer. If you don't have a second port, you can pick up an I/O expansion card with a parallel port and a couple of serial ports for around £20, which still makes this a pretty cheap way to get your PC to speak to you. The WAVE-Play RS unit costs £39.99 including VAT and is available from Speech International ((Contact Details)).

MORE ON PROGRAMMING TOOLS

Last month I mentioned that Voyetra were about to release some multimedia programming tools. These are called Sound Factory, and are due to hit the shops this month. Sound Factory will cost around £150 and consists of a set of Applications Programming Interfaces (APIs) for both MS-DOS and the Windows operating environment. The package comes with support code for the C and Pascal languages and assembly code, and allows the real-time control of digital audio, MIDI, and CD-ROM audio, as well as giving timer and external synchronisation hooks (ie. SMPTE/EBU and MIDI). For more details about this, contact Julian at Computer Music System ((Contact Details)).

MUSIC QUEST INTERFACES

We have some updated information on the Music Quest range of slotless MIDI interfaces, which were mentioned in the July issue of Sound On Sound: these are, in fact, MPU401-compatible, as are all of Music Quest's interfaces.

Errata: An error crept into the September column in the item entitled 'Music Quest Interfaces'. There is actually no physical way in which a slotless interface can be made to be MPU401 compatible. I confirmed this with Music Quest (just in case they'd managed the impossible). The Music Quest item was inserted without my knowledge and was the result of incorrect information being supplied to the editorial staff of Sound On Sound. As far as I know, all the other Music Quest interfaces (apart from the slotless MIDI Engine) are MPU401 compatible.

THIS MONTH'S HELPFUL HINT

It constantly amazes me that so many people don't realise how similar the MS-DOS and Atari ST 3.5" disk formats are. The origin of this similarity is that the ST and the PC's operating system share the same antecedents, namely Digital Research's CP/M operating system. This means that you can read disks formatted on the PC directly on the ST without modification, which is very useful if you want to swap sequences with friends who have Ataris. Just save the data as a standard MIDI file onto a disk that has been formatted to 720k on the PC; this should work for 1.44M disks as well. If you get a disk that has been formatted on the ST and you have access to a disk sector editor, you should be able to make the disk readable by changing the first byte on the first sector of the first side to hexadecimal E9 (or EB for a high density disk) and the last two bytes of the first sector (ie. offset 1FE and 1FF) to 55 AA hex. Thanks to Eric at MidiHelp for this information ((Contact Details)).