Inexpensive, easy to use and able to draw on a growing library of sample cartridges, is the PSP a beginners' toy or the ideal percussive add-on for your MIDI setup?

FOR THE PAST six to seven years, British company Philip Rees have devoted themselves to producing MIDI routing boxes of various kinds, ranging from MIDI Thru units to MIDI patchbays. While other companies have chosen to produce sophisticated MIDI processors with expensive prices to match (the Axxess MIDI Mapper, Audio Architecture's Function Junction and MIDItemp's PM88), Philip Rees have carved their own niche in the market by keeping the emphasis on simplicity and affordability.

It's an emphasis which they've carried through to their first sound-generating box, a MIDI drum expander. With only two controls to be mastered - the on/off switch and a MIDI channel selector knob - the Percussion Sample Player could hardly be simpler to use. No fiddly button-pushing, no poky LCD - but also no sound editing and no programmability. This strictly no-frills approach, which has served the company well in the past, has allowed them to make the PSP one of the cheapest sources of sampled drum and percussion sounds available. But has their pursuit of operational and functional simplicity on the PSP resulted in an instrument which is simply too inflexible to be useful - and is its affordability therefore in truth a false economy?

EXTERIORS

THE PSP COMES in the same 1U-high, half-rack casing used by Philip Rees for their 5X5 MIDI Switch, X5X MIDI Switch Expander and MCV MIDI-to-CV Converter - though of course the front and rear panel layouts differ. In addition to the aforementioned power on/off switch and MIDI channel selector knob, the PSP's front panel contains a power on/off LED, a MIDI activity LED and a slot for a ROM sample cartridge. The free space in the right half of the front panel has been put to good use with a diagram providing a ready indication of which incoming MIDI note triggers which PSP sample.

The PSP's rear panel contains a MIDI In socket, a MIDI Thru socket, Left/Mono and Right stereo output jacks and four monophonic separate output jacks; when you plug a lead into one of the separate outputs, samples routed to it are automatically removed from the stereo pair. The PSP has a built-in power supply together with an integral mains lead which comes ready-fitted with a plug.

The ROM sample cartridges available for the PSP cost a very affordable £19.95 each, and contain eight to 12 samples. As of writing, there are nine cartridges available; a further four are scheduled for June availability, with others planned to follow.

These aren't the slimline credit cards that the Japanese produce, but they're still a fairly compact 1.5" x 1.5" x 0.5", with an edge-connector which protrudes half an inch from the main body. It's this connector which you have to insert (with a firm hand) into the front-panel slot. If the PSP isn't firmly secured in a rack, or you haven't used the four enclosed self-adhesive anti-slip "feet" to secure it to a flat surface, you'll need to anchor it with one hand while you insert or remove the cartridge with the other. Once you get the hang of it, you can change cartridges in three to four seconds - and, once made, the cartridge connection is certainly secure.

Plugging in or unplugging a cartridge can sometimes produce a click on the PSP's audio output, usually slight but sometimes much more noticeable.

Your quick cartridge swaps may be hampered slightly in a live or recording situation by the need to drop the PSP's volume beforehand if you want to err on the side of caution (the expander has no volume control of its own, so you'll have to make any level adjustments on your mixer or amp). This is to prevent extraneous clicks appearing in the music rather than protect your speakers. However, switching the PSP on or off does produce a very noticeable click, so it's advisable to make sure that either your amp is off at the time or that the volume is down on your amp or mixer.

PANNING OUT

SO FAR YOU'VE had the good news. But not all is rosy in the Percussion Sample Player's rhythmic garden. The PSP is only four-voice polyphonic, and has just five internal samples: ride cymbal (cup), crash cymbal and closed, open and pedal hi-hats. Taking internal and cartridge samples together, you can draw on from 13 to 17 PSP samples at any one time, depending on which cartridge you're using - but of course only four of them can be playing at any one time.

The internal samples only respond via MIDI when a cartridge is plugged in - which means, among other things, that you can't have sequenced cymbal parts playing while you change cartridges. Fortunately, when you buy a PSP you get one cartridge free with it, so you can be up and running without having to fork out an extra 20 quid first.

The PSP can be set to receive on any one of MIDI channels 1-16, and responds to MIDI velocity, with actual values being scaled to 16 response steps. MIDI note assignments for sample triggering are preset. MIDI notes 72-76 (C-E above middle C) trigger the five internal samples, which are panned centrally in the stereo image or routed to separate-out four if an audio lead is plugged into that output socket. Each cartridge sample, however, is assigned to the same note in three consecutive C-C octaves below note 72, and the sample's stereo pan position (left, centre or right) or separate output assignment (one, two or three) is determined by which octave you trigger it from. Because these settings are determined by which notes you play, you can select them spontaneously for each "hit" during performance, and also store and edit them within a MIDI sequencer as part of each sequenced rhythm - change the octave of a hit and you change its pan or output setting.

The PSP provides two methods of allocating samples to its four voices. In Fixed allocation mode, triggering a sample from within a particular MIDI octave will always send it to a particular pan position or separate out, in the process cutting short any active sample triggered from the same octave. This is because each octave always uses the same voice, and each voice is "hard-wired" to the relevant separate out and its related stereo pan position. For example, the lowest octave uses voice one, which is routed to separate output one or to the left stereo pan position.

"For the MIDI beginner putting together a budget sequencer-based setup, the PSP scores with its operational simplicity and low price."

In Auto allocation mode, however, a sample only cuts short an active sample which has been triggered from the same octave if there's no other voice spare - if there is a spare voice, the PSP reallocates the newer sample to that voice instead. Of course, this has the effect of changing its output routing and pan position - as if it had been triggered from the octave associated with the voice to which it's been reallocated.

Cartridge samples can only be reallocated among voices 1-3 - voice four is reserved for the internal samples. So that reallocation doesn't get too out of hand, there are a couple of restrictions: a sample retriggered from the same octave always interrupts itself, and a sample is only reallocated if its default voice is being used by a sample triggered from the same octave.

Of the internal samples, only the closed hi-hat can be reallocated - and then only if either the ride cymbal or the crash cymbal is sounding when it's triggered and there's another voice spare (if there's no voice spare, it cuts short the ride or crash rather than a cartridge sample).

Plugging in a cartridge causes the PSP to switch to one or other of these two modes (the factory-preset choice is stored in the cartridge's memory and read by the PSP). You can also get the PSP to switch to a different mode at any time by sending it MIDI controller 126 (Fixed) or 127 (Auto). While this method has certain advantages - like being able to automate allocation-mode changes as part of a MIDI sequence - it's not a lot of good if you're triggering the PSP from a MIDI controller which doesn't allow you to send the required controllers. For the sake of simplicity and immediacy it's a shame there isn't also a dedicated mode-switching button on the PSP's front panel.

THE SOUND OF MUSIC

THE PSP'S PCM samples are eight-bit companded (giving a 72dB dynamic range, equivalent to a 13-bit linear system), and sampled at 31.25kHz. The five built-in cymbal sounds have a neutral (you could say characterless) quality which allows them to blend in with the variety of percussive sounds found on the various cartridges. The longer cymbal samples both succumb to the lack-of-memory syndrome, though as always a touch of external reverb processing can help out.

In addition to the MIDI notes which trigger the internal samples, MIDI note 77 triggers a "choke" function. Pressing this note while one of the cymbal samples is playing causes the cymbal to be choked with a realistic decay rather than just cut dead. This is particularly effective on the crash cymbal, where you could be forgiven for thinking there was a hand inside the PSP damping the cymbal.

The nine cartridges available as of writing are (with number of samples indicated in brackets): Neutral Kit (7), Tight Kit (9), Analogue Drum Machine (12), Techno Kit (7), Latin Kit (10), Power Kit (8), Metal Kit (8), Snare Collection (8) and Tabla (12).

Each cartridge comes in a small plastic box, with a transparent plastic lid which can be clipped securely into place and a piece of foam in the base to help prevent the cartridge from getting knocked about. Also provided in the case is a small fold-out leaflet which includes a list of the samples on the cartridge together with their MIDI trigger notes, a description of each sample, and several example rhythm patterns printed in a grid format. Additionally, each cartridge has a handy diagram printed on its upper face which tells you not only what samples the cartridge contains but also which MIDI notes trigger them.

The Analogue Drum Machine cartridge is dedicated to sounds from the TR808. The three 808 cymbal sounds are absent, and there are two rather than three each of the congas and toms, but interestingly, the standard bass drum is joined by a more clipped version which has been pitched up a bit - something you can't do on the 808 itself. For a number of reasons it would be too simplistic to say you're getting a TR808 on a cartridge - or that you're getting a TR808 for 20 quid - but you are getting a well-recorded selection of 808 sounds.

"Interestingly, the standard TR808 bass drum is joined by a clipped version which has been pitched up - something you can't do on the 808 itself."

You could be forgiven for expecting the Techno Kit samples to be TR909 sounds, but this isn't the case (a 909 card is on the way, though - see below). Instead you get bass, snare and four tom samples which go heavily on the gated reverb, giving them a sort of industrial quality. The only other sample is a rather flaccid, mechanical-sounding handclap, so there's not a lot of variety on offer. You have to really like the overall quality of these samples to want to buy the card.

The Tabla cartridge is the only one of the nine which concentrates on the subtleties of a single instrument - in fact, a pair of hand drums, the tabla (higher-tuned, right hand) and the duggi (lower-tuned, left hand). There are five duggi samples and seven tabla samples, covering different types of strike on each drum. It's a valiant attempt which somehow doesn't quite come out right - the samples lack the crisp sound of the real thing, and there's a lot of extraneous noise on some of the more resonant samples, while the short percussive slap samples fail to capture the proper tone and end up sounding more like mechanical clicks. Yet somehow the end result works very well on its own terms, making the Tabla card quite appealing so long as you don't want to fool anyone that they're listening to real tabla.

The Tabla cartridge defaults to Fixed allocation mode (the only on of the nine cartridges to do so), which makes a lot of sense because it allows you to keep the natural separation of the two drums by playing their samples from two different octaves. The accompanying leaflet provides some background information on the tabla - but sadly no rhythm patterns.

The Latin Kit cartridge is one of the most appealing of the nine, with some crisp, vibrant percussion sounds (including high and low congas, claves, timbale and cabasa) combining very effectively with a woody bass drum and a bright, snappy snare. The other cartridges, mainly variations within the standard kit layout, meet with varying degrees of success (to my mind, Metal Kit and Tight Kit are the least successful). Some samples appear on more than one cartridge - the Neutral, Power and Tight Kits have the same tambourine and the same cowbell, while the flaccid handclap mentioned earlier - which sounds like a pitched-down sample of several typewriter keys clacking together - appears on no less than six of the nine cartridges. Of course, if you only buy one cartridge you won't notice this, but if you buy several you may wonder why you're paying several times for the same sound.

Upcoming cards are Advanced Analogue Drum Machine (TR909 samples), Small Analogue Drum Machine (TR606 samples), Congas (including open, closed, shell and edge variations) and Bongos (as per Congas).

VERDICT

FOR THE MIDI beginner putting together a budget sequencer-based setup, the PSP scores with its operational simplicity and low price. But its four-voice polyphony could very quickly become restrictive if you're relying on it to produce all your rhythm parts, unless all you want it for is to lay down a basic kick, snare and hi-hat accompaniment with perhaps some tom fills or a single percussion part.

With only five internal samples - and those all cymbals - the onus is on the PSP's plug-in sample cartridges to provide both the substance and the variety in the sound department. While these cartridges do offer a sort of sonic expandability, in that you're not restricted to a fixed set of built-in sounds, you can draw on at most 17 samples at a time. To combine samples from more than one cartridge you'd need to sync your sequencer to multitrack tape, then lay the rhythm parts associated with one cartridge to tape, thus freeing up the PSP so that you can plug in another cartridge. If you prefer to sequence all your rhythm parts live in the mix, you could consider buying two PSPs, which would allow you to use two cartridges at the same time - and give you eight-note polyphony (divided as 4 + 4), two stereo output pairs and eight separate monophonic outs. There again, this takes you into a price bracket which opens up new choices: for example, a Cheetah MD16 drum machine with money left over to put towards a sample cartridge which should offer considerably more than 12 samples, or a secondhand Akai S700 sampler which will give you the freedom to sample and combine whatever sounds you want. An S700 and a £30 Mega Beats sample CD could give you all the drum-machine sounds you want (including those of Roland's famous dynamic duo).

Alternatively, for around £30 more than the cost of a single PSP - less than the cost of two PSP sample cartridges - you can buy a Boss DR550 drum machine, which will give you 48 built-in samples and 12-voice polyphony, if not the sonic "expandability" and the separate outs. The DR550 is also straightforward to use - especially if you trigger it from a MIDI sequencer instead of using its onboard sequencing facilities.

All in all, the DR550 probably makes a better budget starter machine. The PSP is more likely to find a role for itself as an add-on to an existing setup. If you want to extend the sonic capabilities of your rhythm setup without having to replace your existing (non-expandable) drum machine and without having to spend big bucks, the PSP could be the best way to go. And in a situation where it's providing selected parts rather than having to shoulder all the rhythmic burden, four-voice polyphony may be adequate.

Ultimately the PSP's value (or lack of it) lies in its sounds. Philip Rees have managed to make a reasonable library of samples available from the outset, but it needs to grow and to be more adventurous. As for quality, these are clearly not the 16-bit 44.1kHz samples which we're coming to expect these days - for instance, they lack the top-end clarity and sparkle and overall vibrancy of such samples. In general the sounds are tight, dry and very upfront, and can sound a bit lifeless - they really need some ambience to help them breathe.

No doubt when the company first thought of producing the PSP they also thought they'd be stepping from one uncrowded budget market into another. But a lot has changed in the meantime, to the point where there's now a glut of affordable boxes which go bump in the mix. The PSP is the cheapest, but it has limitations to match. Perhaps its greatest strength is its sample library. However, from the perspective of PSP as add-on, the existing sample cartridges perhaps concentrate too much on kit sounds and not enough on the sort of percussive sounds you might want to complement an existing setup. This is something Philip Rees need to address if they want the PSP to secure a niche for itself.

Prices PSP, £169.95; each sample card, £19.95. Both prices include VAT (17.5%)

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