"SOUNDS: YOU GOT 9, you got 70, you never got enough..."

I'll never forget those words, spoken to me by a friend who'd just updated his drum machine from an old Roland Drumatix to a brand spanking new top-of-the-range Yamaha. The trouble is, no matter how many sounds you have access to, they're never enough. I find that machines with a veritable armoury of voices often present problems in themselves. For instance, if you have eight snare drum sounds to choose from, you may discover only one or two that you really find usable for your music. On the other hand, if your machine has only two, you don't have any choice but to use them...

But as any imaginative programmer will tell you, the key to finding new voices lies in layering or doubling up existing ones. This can be done in one of two ways. On machines that offer a layering function, compound sounds can be constructed. For example, say the basic sound is a shaker, and you use the layering function to overlay a low volume hi-hat voice. Every time you program a shaker note, the hi-hat will play at the same time.

Alternatively, even if you beatbox hasn't a layering feature, you can still overlay sounds by recording two voices in parallel. To take the above example, you would first program the shaker part. You would then program the hi-hat line, following the shaker part exactly. The same effect, it just uses more memory.

OK, now to get down to applications of the layering technique. For a start, let's talk snares. One of the most interesting experiments you can perform with your beatbox is layering any available percussion sounds on top of the basic snare sound. For example, a common trick to give a snare more cut is to layer a cowbell on top. Usually, the cowbell volume is very low; if you try it, experiment by altering the relative volumes of snare and cowbell in the mix. For hip-hop or genres with a tradition of strange sounds, try using the cowbell at a high volume. Keith LeBlanc often uses this technique, layering a cowbell over the snare or even the bass drum. On the other hand, if you're programming a straight-up rock or pop track, the subtler the layering, the better.

Other percussion sounds you might try layering over a snare include shakers, agogos, conga slaps... anything in fact. One of my favourites is a timbale overlay, with the snare slightly underneath it in terms of volume. Another useful double-up voice — particularly for rock — is the combined rimshot/snare sound. When a live drummer wants to accent a snare beat, he or she will often hit the rim (giving a rimshot sound) at the same time as the head (giving a basic snare sound). The same effect can be achieved by layering a rimshot sound on top of the basic snare voice. Again, experiment with their relative volumes until you stumble across the best results...

And so on to bass drums. I find that great results can be obtained by layering, particularly if you want to "fatten" the conventional short, sharp, modern drum machine bass voice. The commonest technique used is to bung a floor tom sound over the bass drum to beef it up. Unfortunately, on cheaper beatboxes, this doesn't do much good, because the floor tom sound is probably fairly weak — most of them seem to be. Even so, for that resonant seventies bass drum sound, that's the best solution.

Personally, I like using more unusual combinations — say a high tom voice, cowbell (a la LeBlanc) or rimshot. To "tighten" the sound, ethnic percussion voices can help, particularly if they're tuned to a high pitch. Conga slaps work well, as do any Islamic tabla or darabukka voices. But then, you'll probably have to use a sampler to get that somewhere-in-deepest-Afganistan bass drum sound...

Subtle variations on the timekeeping sounds — hi-hat and shaker — can also be achieved using layering. Try using closed and half open hi-hat sounds at the same time (if your machine allows that), or combinations of various shakers, from cabasas to maracas. The sky's the limit...

While we're on the subject of layering, it's worth talking about a technique you could describe as the complete opposite: use of multiple voices but on separate beats.

Take a look at Patterns 1 and 2. You'll notice straightaway that I've layered a cowbell with Snare 1 — that should give it extra cut on the strong backbeat. Snare 2 is deliberately used in contrast to Snare 1. This imitates a common technique used by drummers — playing the backbeat (beats 2 and 4) with a strong stoke dead centre on the snare, but with embellishments played more softly at the edge of the drum. The edge sounds completely different from the centre, so that's why a different snare sound should be used.

The use of two bass drum voices imitates the use of a double bass drum set-up by a live drummer — though he'd find these patterns fairly hard to play without a double hi-hat setup as well! Notice how the use of two bass drum voices introduces dynamics into the patterns without the need for accenting.

Anyhow, it's pub opening time, so I'd better dash. Cheerio until next time; and here's to doubling up...