The pace of change never slackens at the Nippon Gakki factory. The piano makers turned motorbike manufacturers roar in with a new digital rhythm machine, the RX5.

What's black, knobbly and shouts "Hey", "Wow" or "Ooh" according to which parts of its anatomy you press? The answer is Yamaha's new flagship drum machine - or digital rhythm programmer as they would have it - the RX5. A second question might be: 'Why bother with drum machines when sampling keyboards and expanders are available at around the same price or a bit more?'

Yamaha still don't have a pro sampler on the market in spite of strong products from Roland, Akai, Korg and all, who must be eating into Yamaha's synthesizer sales, surely? One Yamaha rep's comment was: "We'll wait till we have finished ours before we put it on the market." Cutting! And not entirely fair.

It would seem that it is only a matter of time before we are merrily sampling the Yamaha way. My feeling is that the RX5 may be the start of something big in this direction. More on this later...

PHYSIQUE

The RX5 is quite a bit bigger than the old RX11 or Roland TR707 drum machines, although you might just get it under your proverbial aircraft seat.

It is very lightweight at just 3.8kg. This makes it feel a bit 'cheap' to me but the value, of course, resides in the research and development that has gone into it and the sounds it is capable of producing - and to me the RX5's value for money quotient seems higher than anything I have yet seen on the electronic percussion market.

FIXING HOLES

To put matters in perspective, let's go back to the RX5's predecessor, the RX11, and briefly examine its problem areas.

Problem number one: the tom sounds. Dreadful! (Yes, I have got one, thank you very much. I use the toms for 'jungle drum' rhythms.) It is my experience as a sound engineer that the better the microphone you use to record toms, the worse the sound. A good old dynamic mic comes up much better than fancy Neumann and AKG capacitor jobs.

The other sounds on the RX11 were good and - importantly - very responsive to equalisation.

Problem number two: no-one seemed sure whether you could sync to tape with the RX11 or not. You could with the aid of the YMC10 MIDI tape sync box, but that cost £99 for a very small package indeed. My RX11, as it happens, would sync via its cassette data output to my multitrack. Other owners I know were not so lucky. (To be fair to Yamaha, no mention was ever made in any literature or in the manual that this would be possible. It just happened that sometimes it was.)

I am pleased to report that with the RX5, Yamaha have done their homework and fixed both these points. The toms are strong and beefy (a bit like me!) and purpose-made tape sync circuitry is included.

So the RX5 is just an updated RX11 with a few new sounds and utility functions? Not quite! I don't think I'll have other manufacturers breathing down my neck if I say that there is no other dedicated drum machine that comes even close to the RX5's abilities for the price.

I think I had better work up gently, so let's start with the basics.

THE SOUNDS

How many sounds should a drum machine have? 16? 32? How about 64?! That's more like it - imagine a 64-piece drum kit. (I can hear the distant sound of minds boggling - now that would make a good sample!)

64 sounds is putting it simply. As always, life is more complex. The RX5 has 24 internal preset sounds. You can add to these in the form of 28 ROM sounds courtesy of a Waveform Data Cartridge that slots into the back of the machine. These can then be edited and the modified voices stored longterm on the RAM 4 data cartridge along with all your pattern and song information. It was not clear to me whether 28 is the limit of voice samples in each cartridge or whether there could be more sounds ready for instant access in future cartridge offerings. Still, 28 per cartridge seems like a good number to me. For the record, there is one cartridge supplied with the machine and more promised to be on the way.

Let's do a quick roll around the preset kit...

Fixed internal sounds:

Bass drum 1 and 2
Snare drum 1 and 2
Rimshot 1 and 2
Toms 1 to 4
Electric toms 1 to 4 (the Simmons influence here!)

Hi-hat open
Hi-hat closed
Ride cymbal played on the edge
Ride cymbal played on the bell
Chinese cymbal (this one you don't have to mount upside down)

Crash cymbal
Tambourine
Claps
Shaker
Cowbell

Cartridge sounds supplied:

Bass drum 3
Snare drum 3
Conga high mute
Conga high open
Conga low

Bongo high
Bongo low
Timbale high
Timbale low
Agogo high

Agogo low
Castanet
Whistle
Timpani
Cuica

Glass crash
Gunshot
FM percussion 1 to 3 (DX7 type sounds)
Electric bass high
Electric bass low

DX orchestra
DX marimba
DX clavinet
'Hey' (sampled vocal)
'Wow' (sampled vocal)
'Ooh' (sampled vocal)

Eyebrows must be rising more by the minute. But what use is one timpani (or is it one timpanus?), it will always be tuned to the wrong note? And how much use can two notes of electric bass be?

If you have been exceptionally diligent you will have been counting up the number of sounds. We have only got to 52. That leaves 12 unaccounted for. Well, the remaining 12 sounds are the ones you have edited from the sounds listed above and assigned to the instrument keys. If you found DX7 programming daunting then here is a drum machine to reckon with - but let me tell you now that it is worth it!

MODIFYING SOUNDS

Any of the above sounds can be changed in several ways. Let's step into 'Edit Voice' mode.

The Edit Voice function comprises nine 'jobs' which can be selected via the RX5's numeric keypad. I shall take a look at the more interesting ones.

Job 2, Pitch.

The pitch of any instrument sound can be altered very accurately in steps of one tenth of a semitone, up to two octaves up or three octaves down. That should be sufficient for most purposes! This means that you can pitch your timpani, as near as dammit, to fit in with your music. This must be the first drum machine you might have to reprogramme if you change the key of a song!

Job 3, Envelope Edit.

This is a six parameter envelope generator which controls Attack, Decay Rate 1, Decay Level 1, Decay Rate 2, Release Rate and Gate Time. This works in a similar manner to the envelope generators in a synthesizer, bearing in mind that the sound you are editing already has its own natural envelope, so what you create is superimposed on this.

The Gate Time parameter is slightly different here. This, in normal keyboard usage, refers to the length of time a key is held down. In the case of the RX5 the instrument keys only respond to the initial strike, so the Gate function is there to imitate a key being held. This is useful for controlling long sounds such as cymbals.

Job 4, Pitch Bend.

An instrument can be set to change in pitch as it sounds, up or down - both the speed and amount of pitch change being programmable.

Job 6 is a simple on/off toggle. When I first got my mits on the RX5 and tickled its ivories, I was amazed at how long some of the sounds were - a marvel of microelectronics, as they say. It was not until I started to read the manual that I found out they were looped samples.

Any sampling enthusiast will know that loops come in three varieties - good, acceptable and YUK! These loops (which are all preset for you) are definitely very good apart from the crash cymbal, which suffers from a slight pitch wobble, but is still very acceptable in the mix.

Job 8 comes in very handy when you realise that you have got so far away from the original sound that there seems little hope of getting back. 'Initialise Voice' is the answer. There is also an 'Edit Compare' function which lets you know whether what you are doing is an improvement. Some of my efforts were not.

KEY ASSIGN

Now that I have told you some of the marvellous things you can do with the RX5 voices, the question is how do you get at them and make music? I could easily say that'Key Assign' enables you to assign voices to instrument keys and output channels and leave it at that. I hope you want to hear more...

As you can see from the photo, the RX5 has 24 (black) instrument keys. If you had X-ray vision you would also see 12 separate instrument output jacks at the back.

Neither 12 nor 24 divide into 64, so there must be a fairly complex system of assignment going on. There is, and I found it difficult to keep track of mentally - partly because you are never really sure of what sound is on the instrument key until you hit it, and partly because I have not had enough time yet for my neurons to acquire sufficient fluency in RX5-think. I suspect the latter would not remain a problem long for a keen programmer.

I just wish there had been some way of indicating which instrument was on which key, but that, of course, would have bumped up the price. Maybe we'll eventually see a deluxe version with go-faster stripes, perhaps...

Let's focus on just two instrument keys for now, A and M - which are the leftmost keys in each row of 12.

The instrument keys all work in pairs, as do A and M, so what I say here applies to all other pairs of keys. Several sounds are available on each pair of keys. Each pair can have two internal voices (in this case Bass drum 1 and 2), two or three cartridge voices (in this case two - Bass drum 3 and Timpani), and also a copied voice.

The internal voices and cartridge voices can be edited as I have described earlier, but they cannot be moved around from key to key, so you would always have a choice of the four instruments I have named on keys A and M, edited or not.

The copied voice is more versatile. This too can be edited or left in its initial state, but it can be any one of the 52 sounds in internal memory or on cartridge. Can you see why I said I had difficulty remembering where the sounds were? Not that I'm complaining. I would much rather have a versatile system that was tough to get used to, than an easily understood but limited one.

The copied voice is also referred to as the 'RAM voice', incidentally. It may sound confusing but the manual is very helpful once you get past some initial waffle; I suggest you start on page 34.

PLAY ME A MELODY

I have told you about voice editing and I have told you about assigning voices to keys. Something completely different is 'Parameter Assign' - job 2 of the Key Assign mode. This is where you change the properties of the instrument keys and therefore the sounds you have on them at that particular moment. This will be important when I come to talk about programming, which is what drum machines are all about.

I do not need to go into too much detail, but in Parameter Assign you can edit pitch, level, attack and decay parameters of any instrument key, changing much the same things as in Edit Voice mode.

'Multi Voice', however, is rather different. This function sets any one chosen instrument sound to all 12 of the topmost row of keys (as on E-mu's SP12 sampling percussion unit). A sliding scale of parameters can then be assigned to these 12 keys. For instance, you could set the pitch of the instrument to vary by one semitone between each key, giving you an octave note range to play with - handy for the timps and especially useful for the electric bass. A-ha! Things seem to make more sense now. Could it possibly be that you can play tunes on the RX5? Could you programme melody lines using the DX Clavinet sound?

Admit it, you would be surprised if I said you couldn't. To be honest, I thought it was a bit of a waste of time messing about with melodic instruments in Multi Voice mode, I could play better tunes on my synth with far less brain ache involved. It was enormously useful, however, for Latin percussion rhythms.

One of the main criticisms of drum machines is their 'machine-like' monotony. If you only have a fixed choice of sounds and a very limited accent capability then the result ought not to be surprising. Suppose, however, that you could record a simple rhythm pattern, then reprogramme the pitch, accent and level data for each instrument, and go back again to add to your pattern. It stands to reason that the end result is bound to be much more 'alive' - depending, of course, on the amount of effort put in by the programmer.

With the RX5 you can do this. You can record, edit and reassign keys; overdub, edit as many times as you like, adding Multi Voice, cancelling Multi Voice. Whatever.

I doubt whether you will be able to change data cartridges as part of this process, but who cares? There is plenty here to be getting on with. I must make it clear that the process described involves changing key-related parameters, not voice parameters themselves. I can't see any way in which this might restrict versatility, but I like to tell it how it is.

PROGRAMMING

I might well have started the review here, as the manual does, but the real meat of this machine seems to be in its voice editing capabilities. Not that it is lacking in the programming department. Real-time and step-time operation are both available, as are variable time signatures, click rate, quantisation, etc etc. However, I wish Yamaha had taken a leaf out of Roland's book as far as step-time programming is concerned. I feel sure Roland's way of writing in step-time while you hear the pattern running is far superior to entering note by note. Some people would no doubt disagree.

A feature that I have not as yet mentioned which deserves a paragraph or two is the 'Damp' function. I told you earlier about the length of some of the RX5 sounds. Indeed, with the envelope edit facility you can keep a sound going for several seconds. Some way of stopping notes is therefore required.

Using the Damp facility while programming in real-time, you enter stop times of notes rather than start times. So, when you want that graunchy Chinese cymbal to make way for something else, you just push the Damp button at the appropriate time and the sound is stopped short. Quantised too! It is one feature which somehow did not seem to be necessary in yesterday's short-sound models.

If you have used a decent MIDI sequencer you will know how useful it is to be able to step through MIDI data and edit out or correct the bum notes. A similar pattern edit facility is provided on the RX5.

You are able to step through any pattern, note by note, or single out a particular instrument in need of special attention. Pitch, level, envelope and reverse on/off can all be changed. (Silly me, I forgot to mention that you can reverse sounds. There is so much available it is hard to fit it all in the review!)

I found it handy to first programme my patterns in a simple manner and then make them more interesting and more complex at this later stage. I think future RX5 owners will find their own ways of doing things, as there is a lot of scope for individuality - a rare commodity on previous drum machines!

One hundred patterns can be memorised of up to 99 bars, which can be linked into 20 songs of up to 999 parts. Three chains of songs can be set and three custom configurations of instruments can be programmed. Need I say more?

MIDI

Hooray! The RX5 has a Thru socket! (Time I sold that RX11 me thinks.) MIDI is comprehensively implemented on this machine, including a version of MIDI Mode 4 known as 'Tunable Note Mode'.

As well as being able to access all 64 notes from a MIDI keyboard (if it is long enough) without reprogramming, you can set 16 individual instruments to the 16 MIDI channels, therefore being able to control the pitch of each instrument sound from a MIDI sequencer. Unfortunately, I really have not had time to explore a quarter of what this machine must be capable of. Some people obviously have...

There are three songs pre-programmed into the machine which superbly demonstrate its potential. Whatever you do, don't simply walk into your local music shop and press the RX5 buttons - ask to hear Funky Up. OK, so the title's a bit naff, but if you can do this with a drum machine...

Shop demonstrators will be glad to learn that these demo programs can be erased from normal working memory but can be restored easily by holding down the left-hand 'Accent 1' button while switching the RX5 on.

HEY, WOW, OOH!

If you have heard that record Jack The Groove, which consists of very little else but the entire contents of the Roland TR707 and TR727, then wait for the Yamaha "Hey, Wow, Ooh" version. Someone is bound to do it.

I am afraid I fail to see the point of putting novelty items like sampled 'grunts' onto the ROM cartridge supplied with the machine, when such appealing instruments as the guiro are missing - and how about a vibroslap? Several of the sampled vocals are going to have little value in normal everyday use, so why waste memory space? Maybe someone from Yamaha can tell me. Perhaps they can also tell me why the power supply has to be external. Does anybody like messing around with such things? I certainly would not like to get to the gig/studio and then find I'd left my RX5 power supply at home. For a machine costing nigh on a grand, you'd think Yamaha could do better.

Sorry about the moan. It was only a small one.

POSSIBILITIES

Right now I can't resist speculating on what comes next from Yamaha. This is what I think - and I have absolutely no inside information - so you don't have to believe me. I may well be talking rubbish.

I reckon Yamaha have a little sampling gadget on the way. I think it will record into those natty little Waveform Data Cartridges supplied with the RX5, so that you can install your own sounds in the machine. I also think that they will bring out a rack-mounting drum machine 'expander' which will not be programmable in itself but will respond to incoming MIDI data. It will also accept these Waveform Data Cartridges, but not sample itself.

This is pure speculation on my part. But as I said earlier - they never stop at Nippon Gakki. In the meantime...

Nice one Yamaha!

Retail price £999 inc VAT.

Details from Yamaha, (Contact Details).