Divorcing a rhythm from the music that usually accompanies it raises interesting issues - some of which are discussed in this month's beatbox programming column.

[Errata: The following drum patterns were the same ones printed in the previous part, so should not be followed. For the correct drum grids, see the next part, part 26, (which is this same article printed here but with the correct grids).]

LOOKING BACK OVER this series, one of the most interesting things I've realised is just how contextualised most rhythms are. Outside the broader divisions which separate jazz, latin and most triplet patterns, and so on, you would normally have to look at the description of a particular rhythm to be sure of the style of music with which it was intended to be used. Though there are rhythmic differences separating house patterns from hip hop and techno from rap, all these rhythms (and most others in contemporary pop) are defined for the most part by the choice of instrumentation, the feel of the song and the complexion of the band playing it. The very fact that you use a drum machine in preference to a real drummer, for example, has as much importance in defining your music as the rhythm it is programmed to play.

For the more enlightened musician this rhythmic interchangeability is of considerable creative advantage; you can experiment with a range of patterns of widely differing feels without being seen to be moving away from the particular style of music you've chosen to be identified with. Rarely has anyone been accused of losing touch with their roots or selling out because of their use of a particular rhythm track.

In the field of dance music, categorisation becomes particularly problematic; notwithstanding the fact that I made full use of the various pigeonholes which exist to divide the series up into monthly chunks, I would, I'm sure, be hard pressed to sift through a random selection of dance patterns and place them in precise groupings. To some extent this is because rhythms simply aren't memorable in the way that melodies are (how many drum tracks can you tap out note for note?). But more importantly it's because they lose many of their identifying features when taken out of context - even if that context is simply the page heading of an instalment of On the Beat.

It is perhaps symptomatic of just how contextualised rhythms have become that a choice of one of two (out of production) drum machines can be instrumental in determining your chosen area of operation. Outside dance music, the divisions are equally blurred; pop seemingly becomes rock when the toms are lowered in pitch and the drummer grimaces each time he whacks his snare. Metal becomes thrash when the tempo is doubled and the drummer strips down to his DMs and bleeds from the knuckles. Rhythmically, there is little change.

To this extent, I have felt much more comfortable with the patterns presented over the last two or three months. Making no greater claim for a rhythm than the fact that it is (or isn't) danceable, or that it perhaps has a jazzy feel to it, is, I believe, an altogether more honest approach and much more in the spirit of experimentation - which was, after all, what this series was intended to foster. I defy anyone to fix firm labels to any of this month's patterns.

Stylistically, the only dividing line one could confidently make would be between the straight 4/4 signature in Patterns 1-3 and the triplet programming of Patterns 4 and 5. Yet in terms of feel, you'd be hard pressed to find five more disparate rhythmic structures. You can't even use the advised tempo settings as a guide to their likely effectiveness on the dancefloor. Pattern 2 ticks along nicely with a very effective groove despite its fairly moderate tempo. Pattern 3 on the other hand, is right on the button in terms of preferred dance tempi, yet would have to run well outside the stated range to be considered anything like danceable.

Pattern 1 would definitely take the award for heavy of the month, but the assurance of the snare drum coming down on beats two and four of each bar give the pattern a much wider range of applications, and it would be particularly effective in a live situation. The tom figure which occurs in bars seven and eight can, of course, be programmed to occur at any part of the rhythmic track, or left out altogether, if you prefer something a little more "straight ahead".

And the same is true of the accented bass drum/open hi-hat beats in bars four and eight of Pattern 3 - although here you might find yourself having to restructure other parts of the pattern to preserve its flow. Pattern 3 is probably the most complex of the patterns from the programming point of view - though anyone who has followed this series will be familiar with the small figures placed in the notes on the side stick line.

These represent the dynamic range which instruments on your machine may be programmed across (one being the lowest level, nine being the highest) and should be divided equally to provide a decaying effect over the course of two bars of the pattern. Notice, however, the first pair of beats comprises notes programmed at dynamic level nine (or its equivalent on your machine) and dynamic level eight. This is important as the first beat of the bar needs to be accented above the level of the subsequent note, As you can see, two bass drums are featured in this pattern - the precise sound of each is not so important as the fact that they both sound sufficiently different. Experiment.

Finally we come to Patterns 4 and 5 - both of which, because of the placement of some of the notes in the bar, have had to be notated on expanded grids with some 12 divisions (we're programming in triplets here) between beats. Beyond this, however, programming is quite straightforward and should reward you with two rather tasty patterns, the second of which is, I believe one of the most insistent grooves I've come up with to date.