Ah... the IBM PC. It is not surprising that a computer originally intended for the small business and hobbyist market doesn't inspire great enthusiasm in the music world. However, all things considered, there is not a great deal of difference between the three major 16-bit computing platforms in terms of hardware. In the past, the major difference between the PC and the rest has been that between a character-based display (the PC) and a graphical user interface or GUI (Mac and Atari). This is no longer the case, due to the phenomenal success of Windows 3.0, and any differences between the various computers' capabilities will be eroded even further by the release of Windows 3.1 later this month (April). So let's cut the chat and get down to business.

You'll be hearing a lot about the new version of Windows (3.1) in the next few months. This will mainly be a result of Microsoft's efforts to separate you from your green folding stuff when you buy an upgrade pack. There are some features in the new release that will be of interest to the PC musician. Version 3.1 of Windows will have a number of Multimedia extensions, essentially allowing Windows applications to control sound hardware in a standardised way. These extra facilities will be a subset of the currently available Multimedia extensions for Windows 3.0, and include software relating to the handling of MIDI interfaces.

The 'standard' sound board for Windows is the Sound Blaster Pro (Westpoint Creative, (Contact Details)). All this means is that the software for this board is bundled with the new release. Other board manufacturers are expected to provide their own drivers that can be loaded into Windows when you install the hardware. A good analogy for this arrangement is the way that Windows handles video cards: a set of standard video drivers is bundled with Windows, and any non-standard video cards will be supplied with a suitable driver that can be installed using the Windows setup utility.

On the subject of MIDI interface cards, if you want to use an IBM compatible (or ISA) PC for music, you'll need to sort out which MIDI card you are going to use. This decision has been made more complicated in the last year or so by a spate of new interfaces with advanced features which have supplemented the more traditional MPU401 type interface. Since multi-timbral sound modules are becoming more common, you may find that having only 16 MIDI channels is a bit limiting. Even quite modest MIDI set-ups can easily break the 16 channel limit.

There are actually two ways to get multiple MIDI ports on the PC. One is to install multiple MIDI cards, and the other is to use one of the new generation of multi-port interfaces. There is no physical problem with installing two MPU interfaces in a PC as long as you can select different IRQ settings for the boards, and as long you have the spare expansion slots required. Or you could get an MPU and a Sound Blaster type card to give you internal sounds as well as multiple MIDI ports. The multi-port cards from Voyetra (Computer Music Systems, (Contact Details)), Music Quest (Digital Music, (Contact Details)) and Roland are a somewhat more elegant solution to the problem, since they only take up a single expansion slot.

Both approaches, however, suffer from the same problem: software compatibility, or lack thereof. To make use of the extra facilities, your software needs to be able to recognise the extra MIDI channels. Needless to say, all the multi-port cards have some form of MPU401 compatibility either built-in or as an optional extra. However, this rather destroys the point of having the extra channels, since the MPU401 standard can only handle the basic 16 MIDI channels. You can only use the extra channels if your sequencer (or other MIDI software) has been written to support them, which rather limits your choice of software.

"It is not surprising that a computer originally intended for the small business and hobbyist market doesn't inspire great enthusiasm in the music world."

Interface compatibility has not been a problem with the PC in the past since most interfaces either used the Roland MPU chipset or emulated it in software. This is not the case with PC multi-port interfaces. To address this problem, Voyetra tried to introduce a software driver system based on the Yamaha C1's CAPI interface, which would essentially make any software that uses it independent of the MIDI interface. I would have thought that most software companies would have jumped at this idea, especially considering the number of C1 versions of popular packages that were produced. Unfortunately a combination of paranoia and apathy on the part of the software producers has meant that very few of them have taken up this option. The upshot of this is that you should check which interfaces your favourite music software can handle before you buy.

On a different tack (but still with Windows software), one of the advantages of using a popular operating system like DOS or Windows is the availability of public domain software and shareware. This is software that is distributed freely via bulletin boards, allowing you to try it out before you decide to buy. If you do decide to buy it you can register your purchase with the author, usually for a very reasonable cost. The biggest hassle is that the authors are usually American — which means that you have to get an international money order or the like. The money order fee is sometimes more than the cost of the software.

A good example of this type of software is Windjammer by Dan McKee (route66/progs area on the CIX bulletin board). This appears to be (I haven't had time to finish checking it out) a fully-featured sequencing package for Windows, albeit without notation, and it supports the MPU401 interface. You also get a MIDI file player that allows you to play your MIDI files in the background whilst you use your computer for other tasks; I'm listening to the MIDI files that come with the package as I type. It amazes me that anyone would spend this amount of effort on developing a package that costs just $50, certainly value for money.

Well, I've run out of space, and I haven't even touched on the new sound cards, the Microsoft MPC (Multimedia PC) standard, and a bundle of other things. Until next time...

(Hint of the month: Most public domain software for the PC expects to see a MPU interface on the IRQ2 interrupt line to be able to work. However, some VGA adapters also use IRQ2 for a light pen signal, which is seldom used — hands up those who use light pens. If you suffer from this problem, you can disable the light pen interrupt by placing a small piece of Sellotape over the appropriate pin on your VGA card's edge connector. The pin in question is on the solder side of the VGA card, four in from the metal back plate attached to the card. Cut a thin strip of tape that will cover the pad up to about 10mm from the bottom edge of the connector and replace the card. Only attempt this if you are happy about taking your PC apart, otherwise a techy friend or relation may be able to do it for you. Obviously this will not work if your VGA card is on the PC's mother board.)