SINCE 1980, when electric drums and drum computers began to infiltrate pop recordings, there has been a crying need for an intelligent, musically flexible rhythm programming system which could utilise the owner's personal sounds.

The drum-kit-in-a-box is now a standard part of pop's instrumentation, but few musicians today are happy with all (or any) of the pre-recorded drums these boxes contain. A "good bass drum sound" may be bad in a different musical context — the groups Test Department and Steely Dan, say, would be unlikely to have agreed on what constituted a good-sounding rhythm track.

In short, variety and customisation of sound is required. Manufacturers have been surprisingly slow to react to this, some offering well-meaning but painfully slow and clumsy custom sound services, others promising sampling facilities which were never forthcoming. Now E-mu Systems, makers of the Emulator and the Drumulator, have developed a machine which promises to make all this simple. It's called the SP12 ("Sampling Percussion") and it's going to make life (or at least the part of it which deals with composing rhythm tracks) easy.

Conceived initially as an improved Drumulator, and referred to for a time as the Drumulator II, it soon outstripped the older machine in concept and design. The SP12 is a new, advanced drum machine with 12-bit digital sampling and 24 pre-programmed internal sounds. It has eight play buttons (which can respond to dynamics), eight faders (which perform a variety of functions), a keypad, several special function buttons, and two cursor buttons. It's blue in colour, medium-sized, and weighs slightly more than a small baby human.

First, for those interested in odious comparisons with Linndrums and the like, let me list the 24 internal sounds, which are arranged in three banks of eight. Bank 1: two bass drums, two snares, two electric snares, rim & cowbell. Bank 2: four toms, four electric toms. Bank 3: two closed hi-hats, open hi-hat, two claps, two ride cymbals, crash cymbal. All these sounds can be tuned up or down and subjected to various levels of decay — thus cowbells can be programmed to play tunes, four toms become 24, hi-hats vary in openness, human claps become those of gnats, and so on.

Next, the sampling; surely the main point of the machine. On the prototype model I tried, eight "user locations" were provided, thereby adding a fourth bank to the three internal sound banks. Sample time was a maximum of 1.2 seconds total, shortly to be expanded (at extra cost) to five seconds divided amongst 40 user locations. Samples are fed into the SP12 via a standard jack socket and then may be truncated at beginning and end (and even subsequently looped) in a simple operation using the faders. Whatever portion of the sound is truncated is then thrown back into the memory pool (or memory jacuzzi, this being a Californian machine).

The sampling quality is excellent, with a fine frequency response and no discernible digital noise. I used up the 1.2 seconds of memory with four samples (two closed hi-hats, open hi-hat, and ambient snare) from a digital tape and found the SP12 reproduced them perfectly. Further experiments with digitally-recorded ambient tom toms, percussion and even voice samples confirmed the sampling quality. I am told by shrewd Californians with soldering-irons that this is the first drum machine to offer 12-bit linear as opposed to 8-bit companding sampling, and although frankly these terms mean as little to me as building society profit and loss figures, my ears — always suspicious — are convinced, and I anticipate five seconds-worth of top quality drum sampling with a certain amount of lip smacking.

Dynamics may be programmed for internal and user sounds alike, using one of two methods; in the first, Dynamic Mode, the play buttons become touch-sensitive with a fairly wide dynamic range. In the second, Multilevel Mode, a selected sound is spread across all eight play buttons at eight different volume levels from ppp to fff (diagram 1). A similar arrangement called Multipitch Mode is available which spreads the tuning of a sound across the play buttons, nominally in the form of a major scale, though this may be adjusted as desired (diagram 2). Thus, if a bass or piano note were sampled, the SP12 could act as a sequencer. Alternatively, the tuning of a sound may be tweaked with a fader while programming.

The unit has MIDI in, out and thru sockets. Applications? Er... ah... play it from a DX7! Um... er... play it with MIDI pads! Well, er, interface box! Mumble mumble — Syco Systems blah blah Roland MIDI pads blah blah August. (That's put the drummers to sleep.)

Like most drum machines, the SP12 is programmed with reference to an internal metronome, and erring, amateurish entries are corrected to the nearest rhythmic value, in this case selectable from quarter notes through to ¹/₆₄th note triplets (or "high resolution"). In addition, step-time programming is possible, useful for writing in 'The Black Page' by Frank Zappa. Patterns are written into any one of 100 "segments", and these can be combined into 100 different songs, in which provision is made for the definition of "sub-songs" (to speed up the process of writing in repetitive groups of segments).

Tempo is programmable from 40-240 bpm with ¹/₁₀ bpm gradations, selectable via keypad or cursor buttons. Or tempo may be defined simply by hitting the Tap button a number of times. The SP12 will look at your timorous prods and respond with a firm, unwavering tempo. Accelerandos and decelerandos may also be programmed into songs. The Tap button doubles as a Repeat button — hold a play button down and hit Repeat; the sound on the play button will repeat at the selected auto-correct rate.

Once the machine's memory is full of segments, songs and user sounds, it will eventually become necessary to save the data to tape or disc. E-mu Systems are working on this at the moment — cassette dump is ready, though reportedly very slow, and data can be saved to disc if one has a Commodore 64 computer with disc drive. (More cash.) It is envisaged that user sounds will be able to be dumped separately from song data, but for the meantime battery back-up will ensure memory retention on power-down (American for turning off).

The godsend of a sampling drum machine is made all the more wondrous by the divine bestowal of another commodity similarly promised but unforthcoming — SMPTE code! Folks — ever synced your drum machine to tape? Know what happens when you stop then restart the tape machine? That's right, the little bastard goes out of sync! Now with SMPTE code (sensibly available in three forms to accommodate the US, European and video standard) your SP12 will stay in sync with the tape no matter how much you stop and start. (Drummers pass into deep comas.)

To conclude in trite style, the SP12 has several other "neat features" such as eight output channels, with any sound assignable to any one channel; programmable output level (with visual display) for each channel; step-time editing for patterns recorded in real time; external clock syncing with a "clock divide" feature; and automatic mains shock through chassis for anyone attempting to program in the drum pattern from "Saturday Night Fever".

Having been selected as a "test site" (guinea pig is a racial slur in California) by E-mu Systems from a list of literally billions of musicians, I am pleased to report a series of successful interfaces between me and the instrument resulting in dozens of redimensioned segments and more duplicated song parameters than you could shake a stick at.

With its strong selling points of sampling and SMPTE, I predict that it will be extremely popular with record producers, groups with record deals, film music composers, studio engineers, groups with no record deal but a bit of cash, even drummers (once something to hit is provided), and me. Over the last year or two I had become increasingly cynical about the limitations of drum machines, but this one restores my faith in the genre's potential for creative musical use.

EMU SYSTEMS SP-12 sample box: £2675 ex-VAT

CONTACT: Syco Systems, (Contact Details)