Sound facilities on personal computers vary enormously. Undoubtedly the best endowed machine in this respect is the NeXT computer, which has built-in 44.1kHz, 16-bit stereo DSP (Digital Signal Processing) facilities. It also offers as standard a hard disk with the storage capacity of a CD-ROM — 650MB — which means plenty of room for memory-hungry sound samples. But with a price tag starting at many times that of other personal computers, a current dearth of music software, and a name that your local dealer may never have heard of, perhaps you ought to think twice before buying one.

More familiar names lower down the price ladder are the Apple Macintosh and the Commodore Amiga. Both computers offer reasonable on-board sound sampling and replay capabilities, though these are of limited use for professional music because they are only 8-bit. However, the addition of third-party hard and software allows professional hard disk recording on both machines, most notable on the Mac. Digidesign hardware can also turn the Mac into a very capable 16-bit stereo sampler.

The Atari ST comes ready equipped with the most useful computer music accessory: a MIDI interface. You can plug a synthesizer straight into an ST, which is no doubt the reason for the huge success it has had in the UK as the musician's computer.

But in the USA, the IBM PC standard reigns supreme in the world of computer music. The IBM PC (the PC for short) is the most successful personal computer ever, in large measure simply because it's from IBM, and because it has been 'cloned' by so many other manufacturers. The PC and its 'compatibles' have sold in tens of millions worldwide. It's a machine you buy without worrying about whether support for it — peripherals, software and maintenance — will be there tomorrow.

Unfortunately, straight from its box, the PC has almost nothing to offer a musician. To be able to make any kind of music on the PC you need to buy extra hardware, to add a MIDI interface or on-board sound facilities, and until recently extra hardware has been expensive. Another disincentive to considering the PC for music has been the fact that the computer itself has had a price tag well above that of the Atari ST.

Over the last year, however, the situation has changed dramatically. The recession has helped to push PC prices down well below expectations — a basic model now sells for as little £200. In addition, a favourable dollar exchange rate means that music software and extra hardware, which come mainly from the USA, are now both cheap and plentiful.

All this means that the PC is now truly the cheapest computer platform for the musician, and were it not for the fact that the basic PC lacks an intuitive Mac/ST/Amiga-style graphic interface, the PC could easily displace the Atari ST from its preeminent position in musical computing. Windows 3.0, the latest PC operating system, does transform the PC to present you with a graphic interface, but you can't run Windows on the cheapest, most basic PCs — the minimum requirement is a machine with a 286 processor.

What extra hardware is required to make music on a PC? Well, expansion of the PC usually involves so-called cards, circuit boards that plug into a slot inside the machine. You have to open the casing and install the expansion card, but it's a straightforward 20-minute job.

There are three different kinds of music-related card for PCs: MIDI interfaces; synthesizer cards; and digital audio recording/playback cards.

MIDI INTERFACE CARDS

A MIDI interface is of course a necessity for running sequencer or voice editing software, allowing the computer to talk to keyboards, sound modules and other MIDI equipment.

A basic MIDI interface has one MIDI In and one MIDI Out, while top-of-the-range models come with two independent MIDI Ins and up to four independent MIDI Outs, giving you a total of 64 channels, and you can also expect built-in synchronisation features. Such MIDI interfaces will stripe a tape with SMPTE and read SMPTE/MTC, so there are savings to be made here since you won't need an external SMPTE timecode reader/writer — a stand-alone unit might cost between £150 and £300, whereas MIDI interfaces for the PC range in price from about £70 to about £350.

Unfortunately, as soon as you start to think about extra hardware the question of compatibility raises its head — will this piece of hardware work with my software? MIDI interfaces are no exception to this rule. The de facto industry standard is the Roland MPU401 (the current model is actually called the the MPU-IPC), and there are MPU-compatible interfaces manufactured by other companies, such as Dr. T, Sound Quest, and Voyetra. Some are very similar to the basic MPU but cheaper, others are more expensive but better. The MPU-IPC itself lies somewhere in the middle as far as quality and value for money are concerned.

The MPU works in two modes: dumb and intelligent. In dumb mode it acts simply as an input/output device (as does the MIDI interface on the Atari ST), but in intelligent mode it carries out work in parallel with the host PC. It can record and play back, keep sync, echo data out and so on, all by itself, saving the PC some work and allowing it to get on with other tasks, and thus preventing MIDI traffic jams.

As processors become faster and faster, speed problems on computers are becoming less important. What is of importance as far as the question of compatibility is concerned is that programs written for the MPU's intelligent mode will not work in dumb mode, and there are a number of third-party interfaces claiming MPU compatibility which are in fact compatible only with the dumb MPU.

Since 99.9% of PC music software is written for or supported by the MPU, there are no problems with buying for MPU-standard interfaces anything like a software sequencers and editors. But if you're buying a MIDI interface which is not MPU-compatible, or not compatible with the MPU's intelligent mode, it's wise to check with the suppliers that the software you wish to run will actually work.

SYNTHESIZER CARDS

Synthesizer cards, sometimes known as sound cards or games cards, are basically variations of existing sound modules and keyboards put on an expansion card. They usually have mono or stereo audio outputs, and can be played directly from the computer via software. Some of them include additional MIDI In/Out facilities, which means that they can also be played from an external source such as a MIDI keyboard or an external sequencer.

Though a number of these cards are manufactured by computer companies and marketed as computer peripherals, if you take a close look at the chips on the card you might find names that look very much like "Yamaha", "Roland", "Emu" and so on. The chips are in fact variations of — or sometimes identical to — those found on keyboards like Yamaha's PSS range (FM), and on the Roland MT32 and SC55 sound modules; there's even an Emu Proteus on an expansion card, as we shall see in a moment.

A number or these cards also offer CD-quality digital recording facilities, something to which we shall now turn our attention.

DIGITAL AUDIO CARDS

A digital audio card allows you to turn the computer into a digital tapeless recorder, usually for editing master recordings or tracks of acoustic instruments and vocals.

In its most basic form, this type of card includes only audio analogue input and output (mono or stereo). While recording, the input signal is sampled and written directly to a file on disk, and the opposite process takes place during playback.

More sophisticated models include digital input and output, so you can transfer data back and forth to a DAT machine, and implement MIDI and/or SMPTE sync, multiple track recording and even data compression. There are a number of cards offering professional quality and facilities which, as you might expect, are relatively expensive (over £1,000), the French Digigram PCX-3 being one example. On the other hand, the Turtle Beach MultiSound card includes the equivalent of a Digidesign AudioMedia board and an Emu Proteus, for considerably less than the price of buying the two separately, so these cards are still good value.

You need a large hard disk to support digital audio cards, because you'll need around 10MB to record each stereo minute with CD-standard encoding (16-bit, 44.1kHz), and this is exactly where the PC becomes an attractive proposition: hard disks are cheaper than for other machines.

A £500 PC will include at least a 20-40 MB hard disk, while an additional 250MB hard disk costs about £400, though you always get a much better deal if you buy a machine with a large hard disk to start with.

SYNTHESIZER AND DIGITAL AUDIO CARDS

One of the first synthesizer cards for the PC — and here we're going back five years — was the IBM Feature card. With a Yamaha sound chip, the IBM stamp, and 4-operator FM sounds as found on the FB01, it wasn't bad for its time. Sadly, it was not this card that became a standard, but rather the much cheaper AdLib card, based on another Yamaha FM chip (the YM3812), which incorporated only 2-operator synthesis. This chip, still in use on a number of cards, is 11-note polyphonic and uses two different multi-timbral modes: either 11 musical parts, or six plus drums. The sounds are identical in quality to what you get on the old PSS (FM) range of Yamaha home mini-keyboards.

After the Adlib card, came the Sound Blaster, which also used the Yamaha YM3812 chip, but added mono sampling, allowing you to record up to 22kHz at 8-bit resolution. Because of its digitised sound capabilities, Sound Blaster became very popular with games manufacturers and was soon to become a standard in its own right.

Other cards of very similar specifications are available from companies such as Covox and Media Vision. Covox's Sound Master II is the only one which has software for speech recognition, allowing a degree of speech control over your PC. Media Vision's Thunder Board has quite a good integral sound editing program.

These cards are the most basic. They're cheap and ideal for games but, being mono, not to mention the tinny quality of the sound, they're unsatisfactory for serious musical applications.

For synthesizer cards which produce sounds more suitable for serious music, you have to turn to Roland again. Roland's L4PC1 is an MT32 sound module on a card, but it comes at a price higher than the sound module itself and with MIDI as an extra, so it hasn't caught on.

As musicians, we would have been happier if the computer industry had adopted Roland's chip as the standard instead of the one used on the AdLib card, but Roland maintain that they're interested in quality not quantity. This marketing strategy can't help but remind one of the Yamaha C1 Music Computer. This superb machine was launched, overpriced, at £3,000, and sold off a year later at £1,250, branded as a failure.

"Unfortunately, straight from its box, the PC has almost nothing to offer a musician. To be able to make any kind of music on the PC you need to buy extra hardware."

However, with manufacturers anticipating the multimedia revolution (see box on multimedia), many new cards are being introduced this year, including the Roland SCC1, a card version of the Sound Canvas with a built-in MIDI interface. This time, Roland have set the price at a fair level (£335).

The SCC1 offers 24-note polyphony, 16-part multi-timbrality, 317 sounds, nine drum kits, and a sound effects kit, as well as reverb, delay and chorus effects. It conforms both to the General MIDI standard, and to Roland's GS standard (a 'special case' extension of General MIDI), which define such things as the positions of piano, strings, trumpets and other sounds in the program change allocation table. As it happens, the GS standard is also incorporated in Microsoft's Multimedia Extensions to Windows (again, see box on multimedia).

Creative Labs have released Sound Blaster Pro, a stereo version of the old Sound Blaster card that offers mono recording up to 44.1 kHz and stereo at 22kHz, and a built-in interface to which you can attach a CD-ROM player (so you can play audio CDs while you work!). The card comes with a wide selection of software, and is probably the best value for money of all the synthesizer cards mentioned here. The software includes Voyetra's Sequencer Plus Jr., and there's a program that combines computer animation with digitised sound and music. And for those interested in light entertainment, there's a talking parrot game, a program that 'reads out' text files in computerised speech, and an interactive agony uncle called Dr. Sbaitso whom you can consult about your personal problems!

Media Vision's Pro Audio Spectrum card is very similar to Sound Blaster Pro, but doesn't come bundled with as many programs. It can, however, record stereo at up to 44.1 kHz, and it does come with a program which allows you to edit the FM sounds contained on the card. As with Sound Blaster Pro, the Pro Audio Spectrum includes Voyetra's Sequencer Plus Jr., but the MIDI In and Out sockets are extra.

Even though Sound Blaster Pro and Pro Audio Spectrum cards offer stereo audio, the chips used are the same as on the old versions. Another card, however, the Gold 1000 announced by AdLib, which should have been released by the time this article goes to press, offers great improvements in both synthesised sound and digital audio recording. It sticks to Yamaha's FM synthesis, but uses four operators and eight algorithms, instead of two and four as on the old card.

On the digital audio side, Gold 1000 offers 12-bit recording resolution rather than 8-bit. This is probably the minimum requirement for fairly serious music; certainly not CD-quality, but our ears haven't changed — we happily used 12-bit samplers like the Akai S900 and the Roland S10, three or four years ago. The new Ad-Lib card also improves on its predecessor by offering 20-note polyphony instead of eight.

Optional extras on the Gold 1000 card include 'surround sound', and a telephone interface which turns the computer into an answering machine.

Turtle Beach's MultiSound is an outstanding piece of hardware, offering the most professional combination of facilities for music and digital recording on a single PC card. It incorporates mono or stereo, 8 or 16-bit recording/playback at 44.1 kHz, 22.05kHz and 11.025kHz, and includes a Proteus 1 synth module (32-note polyphonic, 16-channel multi-timbral, with 126 16-bit sampled sounds stored in 4MB of memory). This unit is now available in the UK for £949.95, a bargain for what it offers if you consider that the Proteus 1 alone is about £600.

However, if you want stereo digital audio at low cost, and don't want to pay extra for synthesizer facilities, there is a small but growing number of cards that fit the bill. Digital Audio Labs manufacture the CardD which offers recording at 32kHz, 44.1kHz and 48kHz, uses 16-bit A-to-D and 18-bit D-to-A conversion, and manages a reasonable 92dB dynamic range. It comes with a comprehensive graphic editor program which lets you manipulate the recording using zoom in/out, cut, paste, mix and such like. In addition, you can set up a catalogue of files which you can load and play by pressing predefined keys, or by selecting them from a list. An optional S/PDIF digital I/O allows you to hook up digitally to a domestic DAT machine, and optional software includes audio editing for video applications.

Another such product is Gloria, a multimedia digital audio card marketed by Catalyst. This offers 16-bit recording at 16kHz, 32kHz and 44.1kHz, with a signal to noise ratio of over 75dB. It has basic editing facilities which include mixing of sound tracks, but offers no digital I/O. It can synchronise internally to software running computer animations created by Autodesk's Animator software, which is rapidly becoming a standard for PC animation.

Also worth looking out for is the PC version of the Plasmec ADAS system (Atari version reviewed SOS November 1991).

THE CHOICE IN A NUTSHELL

Many musician's perceive the PC as a poor choice of computer for music, but a cursory examination of the market reveals plenty of quality music software, and plug-in cards that can put a mouthwatering selection of synthesis and digital audio hardware inside your computer, probably for a good deal less than you'd pay for stand-alone equivalents.

For PC musicians on a budget, the Sound Blaster Pro is very good value for money since you get a synthesizer, digital audio, Sequencer Plus Jr., and a MIDI interface. If the digital audio isn't so important, the Roland SCC1 offers superb Sound Canvas-derived sounds.

Moving up in price, if you want adequate music and reasonable digital sound facilities, wait for the new AdLib Gold; the Turtle Beach MultiSound offers still more on both counts, and might make some Mac owners with MacProteus and AudioMedia boards feel hard done by.

Lastly, if you're interested only in professional digital audio at low cost, and no synthesizer on board, the CardD will satisfy your needs.

Further information

Catalyst (Gloria) (Contact Details).
Computer Music Systems (The CardD) (Contact Details).
Covox Europe (Sound Master II) (Contact Details).
Dimensional Services (ThunderBoard) (Contact Details).
MCMXCIX (Turtle Beach MultiSound) (Contact Details).
Mindscape (AdLib) (Contact Details).
P & P (Pro Audio Spectrum) (Contact Details).
Roland UK (SCC1, LAPC1) (Contact Details).
WestPoint Creative (Sound Blaster Pro) (Contact Details).