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Ensoniq ASRX

Sampling Workstation By Chris Carter
Published September 1997

Using a separate sampler, sequencer, synth and drum machine? With the new Ensoniq ASRX you could take just one box into the studio. Chris Carter just samples and goes...

Ensoniq have made a brave move with this hybrid sampler, because in deciding to enter the Akai‑dominated sampling workstation market they could have come unstuck rather than coming up trumps. Although products such as the Korg Trinity and Roland DJ70 MkII share a few features and concepts with the ASRX, it's the Akai MPC2000 (see SOS April '97) that is its most direct competitor. However, although the MPC2000 may be more highly specified in the sampling department, it doesn't offer the ASRX's built‑in ROM sounds, effects as standard, or resampling. If you're looking for a sampling drum machine, check out the MPC; if you're looking for a sampling workstation, read on...

X‑Ray Specs

The Ensoniq ASRX is a pro‑specification 16‑bit stereo sampler/resampler, with built‑in MR synthesizer, multi‑effects, 18dB resonant filters, 32‑voice polyphony, a multitimbral, 16‑track MIDI sequencer, 14 real‑time performance pads, 2Mb of RAM and a floppy disk drive. The unit can be expanded with a further 26Mb of ROM voices and 32Mb of RAM, and an optional expander board offers an additional eight assignable audio outputs and a SCSI facility.

Although described by Ensoniq as a portable unit, the ASRX is a substantial beast, in terms of both its build quality and its size. The pressed steel casing measures about 17 x 13 x 4 (inches) and, apart from a couple of slightly flimsy protruding controls on the back, looks and feels as if it were built for life on the road. The expansive front panel is divided into two sections and contains a small, backlit, 2‑line x 20‑character LCD and 40 or so controls. In the upper section is a volume control and two continuously variable knobs labelled Parameter/Sound Type and Value/Sound Name. The Parameter knob is for scrolling through sound banks (using the 'SoundFinder' feature — see 'SoundFinder' box) and browsing parameter pages. The Value control is used to scroll through sound names (within sound banks) and to change parameter values. Unfortunately, there are no +/‑ incremental buttons for fine‑tuning values, nor any way of making large parameter leaps, which means that a lot of knob‑twiddling is the order of the day.

Some of the 21 small oval push‑buttons have useful built‑in LEDs, and many of them perform multiple functions — some can call up a parameter page when you double‑click on them, as you would using a mouse with a computer, and repeatedly clicking causes some of the buttons to scroll through parameter pages, so that you don't have to use the parameter knob. Both these methods take a little getting used to, but do open the way to some useful and speedy programming shortcuts. The lower half of the front panel contains the sampling section, transpose and Patch Select buttons (see 'Patch It Up' box), and 14 velocity‑sensitive pads.

On the rear panel are jack sockets for left and right audio inputs and outputs, a stereo headphone socket, a dual footswitch socket, MIDI In/Out/Thru connectors, an input‑level control, a mic/line input selector switch, and a couple of blank panels waiting for the various upgrade options.

The Sound Of Waves

In operation the ASRX follows most sampler, synth and sequencer conventions and, apart from a few quirks and idiosyncrasies, is fairly straightforward to use. One of these quirks is the lack of a battery‑backed system, patch or performance memory, which means that a stash of floppies should always be close to hand, for quick saving of any edits.

Raw samples and ROM voices in the ASRX are called Waves, while programmes or performances containing them are, a little confusingly, called either Kit Sounds or Standard Sounds. Standard Sounds are made up of a maximum of 16 layers of individual mono or stereo waves spread chromatically across the front‑panel pads. A Standard Sound can be used for anything melodic — from synth, bass, guitar or samples, through to highly complex evolving pads or sound effects. Bear in mind, though, that preset ROM Sounds using a lot of layers steal notes from the total 32‑note polyphony. Kit Sounds utilise a structure where each note, from B1 to D7, can play an entirely different mono or stereo wave. You could have a mixture of 64 percussion sounds, sample loops, Standard Sounds or even other Kit Sounds programmed onto individual pads or MIDI notes.

There are half a dozen or so drum kits in ROM, and while they're pretty high in quality they aren't particularly outstanding — a bit too 'rock and roll' for my liking — and as this is a dance‑orientated, 'groove' instrument, I feel a little effort should have been put into providing more colourful kits.

On The Right Track

Central to the operation of the ASRX is the concept of Tracks. These are actually sequencer tracks (with Track 1 tied to MIDI channel 1, Track 2 to MIDI channel 2, and so on), and there are always 16 active Tracks, no more and no less, even if you haven't recorded anything.

To listen to or record a Sound or Kit, you first choose a track, using the dedicated Track Select buttons below the LCD. You then scroll through the ROM voices, using the SoundType and SoundName knobs and the SoundFinder feature. In this mode, the display always shows the Track number and the Kit/Sound playing, and the sequencer bar and beat numbers. And while the pads will only play and record the currently selected Kit/Sound, you can play and record Kits/Sounds on other, non‑visible Tracks over MIDI. Using the Track Select and SoundFinder functions it's possible to jump from track to track changing Sounds and Kits very quickly, until you're happy with the setup — easy‑peasy so far.

Once you've chosen a Sound, you can tweak and adjust it using the Track Edit button. The pages revealed by this button contain 40 or so editing parameters, such as volume, pan, effects routing, octave shift, VCF, ADSR, LFO and portamento. These parameters either override or offset the original programmed Kit/Sound settings, depending on how the Track Parameter function is set; many of the parameters can also be controlled by an external MIDI source and subsequently recorded into a sequencer track.

Take Notes

While the ASRX's sequencer may not be as versatile as a computer sequencing program, it's no slouch. All the usual suspects are here, plus a few surprises you wouldn't normally expect in a hardware unit. Up to 128 sequences can be loaded (memory permitting), and sequences can be saved as standard MIDI files to DOS‑format floppy, for loading into most PC, Mac and ST sequencer packages. The sequencer has a resolution of 384ppqn (pulses per quarter note) and several recording modes:

  • Replace mode erases any previously recorded material.
  • Add is the default mode, and combines new material with previous material.
  • Step mode is for non‑real‑time recording.
  • Track Mix mode allows you to record real‑time Track Volume and Track Pan changes.
  • Final Mix mode is for recording Sequence Volume and Sequence Tempo changes.

The Regions feature lets you define a section of a currently selected sequence for various uses — as an auto punch in/out region, for example, or as a section you want to copy, erase or play back. Everyday tools include programmble Tempo and Time Signature, Undo, Copy Track, Append, Replace, Merge, Erase Track, Erase Notes, Erase MIDI Controllers, Scoop (for removing individual notes) and Quantise. The Quantise function is very comprehensive and has enough features to cover most situations, with parameters including Strength, Swing, Random, Shift, Note Range, and Min/Max Deviation. You can apply varying quantise amounts, and Ensoniq include their own Delta Quantisation, a method of analysing the space between notes for a less strict and more rhythmic approach. You can also choose from a list of quantise templates, including Strict, Tight, Random, Swing and Humanise, or save and load your own custom templates.

The only real let‑down here is the sequencer controls — or lack of them. The transport controls (Record, Stop and Play) also double as Rew and FFWD and Locate, Scoop and Top (return to zero). To record, you have to press Record and Play together, which is OK, but to rewind involves pressing Record and Stop. This isn't so good, particularly if the lights are low (on stage?); in fact, because the buttons are small and black on black, I accidentally dropped into record on more than one occasion. The fact that the Play button is also used for return to zero (you have to double‑click on it) and fast forward (you have to hold down Stop and Play together) can be confusing. A dual footswitch can be connected and configured to trigger Record, Start/Stop and other sequencer functions, but it's not an ideal solution.

I don't really understand why these controls have been so poorly implemented, but on the whole the sequencer is very easy to use. Creating a new track from scratch is very easy — just two button presses — and recording and playing back couldn't be simpler. You can scroll through various Kits and Sounds while playing back sequences, to try out different ideas, but unfortunately not in Record mode. Editing sequences is a bit tricky, because of the small display, but if you have access to a computer you could load your work into a that for extra tweaking and then load the work back into the ASRX. With space for 128 sequences, you can work on songs and ideas ad infinitum — just don't forget to keep saving your work!

Welcome To The House Of Whacks

To be honest, I was surprised at how quickly I came to rely on the performance pads for entering notes into the sequencer, and in fact the pads become pretty essential once you do any serious work on the ASRX, because although they sound and look a bit clunky they are in fact quite responsive and allow you to work out ideas, rhythm patterns, basslines and basic melodies very quickly. However, because the pads only cover a physical range of 13 notes, C to C (with a transposable range of five octaves, using the transpose buttons) things can get awkward if you plan on entering a lot of chords or playing delicate, fast or full‑length keyboard runs, in which case a MIDI keyboard is best kept connected and nearby. Also, while the pads have probably been designed primarily for entering rhythms patterns, I'm not sure they would stand up to being whacked with drum sticks — well, not too hard anyway.

The response of each pad can be edited to suit your personal playing style, or the style of the music involved. This means that you can build up a collection of favourite custom kits for different projects, songs or even different users. However, in order to edit the pads, you must first convert a Kit from ROM to RAM. The Kit can be an existing one or you can convert the 'Silence' Kit (which contains nothing) as the basis for a completely new custom kit of your own. If you begin editing a Kit without copying it to RAM, the LCD asks: 'Make a RAM Kit from [for example]: ROM10:004 Rock Kit?'. Pressing the Yes/Enter button is usually the way forward, and a copy is placed into RAM. You can now alter velocity, pan, tuning and FX buss assignment for each pad or MIDI note, and when you tap a pad (using the Transpose buttons to cover the full five octaves if necessary) the display changes to show which sound is selected for that pad. You can scroll though the 128 ROM Sounds (or more, if you have an MR‑EXP board fitted) or any RAM samples, adapting the Kit to suit your needs. The edited Kit now appears under a new category, called USER‑SND, in the SoundFinder list, and can be renamed or used within other Kits and Standard Sounds. The ROM banks contain six slightly lacklustre drum kits and one GM kit, and the manual provides Ensoniq and GM drum maps to help when adapting ROM kits or making your own from scratch. This methodology is pretty fast and straightforward, but I think Ensoniq could have included a few more kits in ROM.

Scratching The Pad

The ASRX's sampling section (derived from the higher‑specified Ensoniq ASR10 and ASR88 samplers) is tucked away in the bottom left‑hand corner of the front panel and only reveals itself via three buttons: Setup, SendToPad, Start/Stop, and a dedicated velocity‑sensitive pad called the Scratch Pad.

To prepare for sampling, you press the Setup button repeatedly, and this causes the display to scroll through all the sampling options. (Alternatively, you can scroll using the parameter knob.) The sampling pages allow you to configure sampling time, set a pre‑trigger level, sampling trigger (manual, MIDI or audio), input source, mono or stereo sampling, and view the input level meter. Input Source options are Input Dry, Input+Insert, Input+Main Out and Main Out only. The first three options are for sampling external sounds; with the last two, the ASRX enters resampling territory by sampling its own output (more on this in a moment). When you're sampling from an external source, you set levels with the help of two LEDs on the front panel, and/or the Input Meter page. Once the parameters are set, and assuming that there's an audio source connected to the rear jack sockets (although if you are resampling this isn't strictly necessary), it's just a matter of hitting the sampling Start/Stop button, and it's chocks away...

You can stop sampling at any time by pressing the Start/Stop button or, if you've pre‑set a sampling time, just wait until sampling has finished. The sample is now temporarily available on the Scratch Pad button (until you sample something else), and the display reads 'Send To Pads?'. What you do now depends on the type of sound you've sampled. If your sample is a loop or a percussion sound, you'll tap one or more of the pads of the currently selected RAM Kit and your wave will be copied to that pad, becoming part of the Kit. Alternatively, you can select a new RAM Kit (or an empty Kit) at any time and press the SendToPad button, which brings up the 'Send To Pads?' dialogue again. However, if your sample needs to be spread chromatically across all the pads (or MIDI notes), you press the Track Sound button, dial up the 'Custom' category on the display and select your sample, which now appears as a Standard Sound. All new samples are automatically named SMPL_001, SMPL_002 and so on, and placed in the Custom category as Standard Sounds, but they can be renamed at any time.

... this machine is a great compositional tool, and its wealth of features and size make it ideal for a home or project studio.

Ensoniq have wisely made the ASRX's resampling feature the default sampling mode, which means that it's very quick and easy to use, as you don't need to do much (if any) fiddling around to set it up. Anything can be resampled — sequencer or MIDI controlled, Kits, Sounds and samples, live pad playing, external audio (plus effects), the master stereo output (plus effects), external audio and the master stereo output together (plus effects, of course!). I know it's a cliché, but the only limit to what you resample is your imagination and the amount of installed memory.

Also, if you find yourself exceeding the 32‑note polyphony, or need more effects, you can resample as you go, freeing up complex rhythm tracks, or dense pad sounds. If you have enough memory (and I think 16Mb would be the absolute minimum), it's quite possible to resample a whole song, complete with effects and in stereo. You can then place the sample in a Kit and treat it as you would any other sample or loop, processing and manipulating it. You could then resample it again, adding to it and mutating it until the original is quite unrecognisable. A major bonus here is that because everything is carried out in the digital domain there are no levels to worry about and no noticeable degradation of the resampled audio — unless you're using distortion effects, that is. This is sampling at its most fun. Note that you can't resample at lower sample rates to save memory; you have to use the Reduce Sample Bits function for this (see next section).

Sample Editing

Sample editing is fairly rudimentary but, as a result, quite straightforward. There are eight sample pages, allowing you to determine such things as sample/loop direction, and providing the facility to make coarse and fine adjustments to sample and loop start and end points. You also get a few Sample Process options: Truncate Length, Normalise Gain, Scale Loudness, Invert Sample Data, Copy Sample To Pads and Reduce Sample Bits. This last one is great for grungy sounds, and works in 1‑bit steps, all the way down to 1‑bit resolution, if needed. But sorry — there are no fancy waveforms and editing graphics here; everything is performed numerically or by ear, and there's no sign of crossfade looping or time‑stretching.

As you would expect, sample trimming and looping can be a slow and frustrating process, with no visual feedback to speak of. But once you're happy with the basic raw sample, there are plenty of sound‑shaping tools to play with. These so‑called Pad Parameters include volume, pan, tuning, effects routing, a 3‑pole, 18dB resonant filter, a VCF + envelope generator, a VCA + envelope generator, a pitch envelope generator, an LFO/modulation section, portamento and MIDI modulation. The filters and modulation options are particularly good, and there's enough here to mangle a sample out of all recognition.

Insert Your Effect Here

The effects banks in the ASRX utilise the 24‑bit ESP2 chip, the same used in Ensoniq MR synths. Two effects are available per sequence — insert effect and global reverb — and any or all of the 16 Tracks can be routed to these effects busses. If the X8 output expander is fitted, an additional four busses are available. These feed four pairs of stereo outputs and can be used to send Sounds and Kits to external effects units or mixer channels. The insert effect buss can use one of the 40 listed effect algorithms but the global reverb buss can only select from eight specific reverb effects (see 'Effects Algorithms' box). This may not offer the overkill approach of some samplers and workstations, but the ASRX does provide a considerable number of editable parameters per effect, with most having at least 20 to 30 editable values. To get around the problem of excessive page scrolling and knob‑twiddling with this many parameters, Ensoniq have included some very useful presets for each effect. For instance, the plain‑sounding 'Formant Morph' effect has eight presets, ranging from 'Vel Vocoder' (a very convincing voice box sound) to 'Synced Saws' (which sounds like someone with a cold saying "bye bye bye..."). Alternatively, the presets can be used as starting points for a new effect of your own and can be manually overridden. Looking at the list, you'd assume that the maximum number of insert effects available would be three, as in the EQ‑CHORUS‑DDL chain; however, the effects list doesn't give the full story. For example, the
DIST‑DDL‑TREM effect has 31 editable parameters and 10 preset algorithms, and contains a high‑pass filter, voltage‑controlled harmonic distortion, a VCF, 3‑band EQ, a delay and an LFO — and great it sounds, too. As you'd expect with 24‑bit processing, all the effects are noise‑free and professional‑sounding, with some very musical distortions and filters, and lush, wide choruses. The formant filters are exceptionally good, and can turn a bland loop or pad into an altogether different animal. The global reverbs are very natural (and American) sounding, with none of that metallic ring you often get with Japanese effects; they could easily stand shoulder‑to‑shoulder with most mid‑priced dedicated effects units. In addition, each Insert effect provides a set of parameters to allow you to manipulate it in real time over MIDI. To achieve this, a sequencer Track can be assigned as an Insert Effect Control Track, and an Effect Modulation Destination and a Modulation Source can be programmed. Any effects changes are then recorded, along with MIDI note information, into the chosen sequencer track. This is a useful feature for introducing even more expression into an already expressive instrument, particularly when used with the resampling function.

The Ultimate Groove Machine?

Since this is an instrument that Ensoniq are advertising as the 'Ultimate Groove Machine', where are those essential looping tools such as a loop bpm calculator, or features such as 'Beats Mode' and 'Beat Change' found on the dinky Akai S20 and gargantuan Yamaha A3000 samplers, which calculate, then stretch or squeeze sample loops to a set bpm value? There is a rather feeble Tap Tempo button, but it's too unpredictable to be of any real use. With a bit of luck, these omissions can be remedied in future software revisions.

There were definitely times with the ASRX when I longed for a decent‑sized display and a few more dedicated function buttons. For live use, the small lettering and 'black buttons on black background' colour scheme is well dodgy — you'll definitely need a torch or gooseneck lamp at the ready. I like sampling on the ASRX — it's easy, it's fast and it sounds good — but quite why the input‑level control has been placed on the rear panel is a total mystery. This is a sampler, for goodness' sake! Whoever heard of putting the one control that stands between it and the outside world in such an impractical position? If you were using the ASRX live, I also think the input‑level control and the mic/line switch (both on the rear) would be vulnerable to being snapped off by some dozy roadie.

But these are just my own petty moans, and I'm not trying to put anyone off, because the ASRX is a monster of a machine, in the nicest possible way, and would make a good choice for live work, being sturdy and compact and a lot easier to transport around than a separate sampler, synth, sequencer and effects unit. You could even dispense with your Octapad and keyboard, if you didn't mind using your fingers to tap out rhythms and you didn't anticipate needing to play opposite ends of a 5‑octave keyboard at the same time. Being both easy to use and decent sounding makes this machine a great compositional tool, and its wealth of features and size also make it ideal for a home or project studio. Although the individual sections may not have the bells and whistles of dedicated units, they are integrated in such a way that the ASRX can be used without recourse to any other equipment (except an amp and speakers) to produce some very polished and professional‑sounding arrangements.

Waving Goodbye

If you bought a separate sampler, synth, sequencer and effects unit, not to mention the pads, the cost would definitely be much higher than an ASRX. But here's where things get a little wobbly, because separates would probably be slightly higher specified, particularly in respect of the ROM voices, which are few and a little uninspiring by current standards. The superb (optional) Urban Dance Project Wave Expansion board should really be included in the price, not least because the ASRX is supposed to be a dance 'Groove Machine'. And since the installed RAM is shared by the system, synth, sequencer and sampler, why is there only 2Mb? When I raised this with Key Audio (the distributor) even they admitted that this left little memory for any serious resampling.

So what's the verdict? Well, I have to own up to having a bloody good time reviewing the ASRX and, apart from a few pretty small reservations, can definitely recommend it. If you can budget for the MR‑EXP‑3 Wave Expansion board and additional memory, buy one and enjoy.


  • ASR stereo sampler with 44.1kHz sampling rate.
  • MR synthesizer, with 128 preset ROM voices.
  • 16‑track MIDI sequencer.
  • 24‑bit effects, Insert and Global.
  • 32‑note polyphony.
  • 16‑part multitimbrality.
  • 14 velocity‑sensitive pads.
  • 18dB resonant filters.
  • 20‑bit A/D converters.
  • 2‑line x 20‑character LCD.
  • 2Mb onboard RAM.
  • DOS‑compatible disk drive.
  • Saves AIFF and loads AIFF and WAV audio files.
  • Saves/loads Standard MIDI Files.
  • Ensoniq audio sample CD and demo disk included.

Patch It Up

Next to the performance pads are a couple of innocuous buttons labelled Patch Selects. Existing Ensoniq users will already know all about these buttons, as they've been appearing on Ensoniq products since the first EPS sampler from way back; thoughtfully, the ASRX can also read Patch Selects layers from the existing range of MR Wave Expansion boards. If you don't know what they do, here's a brief outline.

Pressing different combinations of these buttons (left down, right down, both down) can introduce up to four variations to many of the ROM Sound presets that have been programmed, with two or more layers. In the default state the buttons are momentary and only affect the Sound while held down, but they can also be programmed to latch on until pressed again.

For example, the ASRX preset 'ROM09:017 Squared Off' is a ROM sample of a couple of synth square waves with a touch of detuning. Pressing the left Patch Selects button introduces a pleasant overtone, while pressing the right button superimposes a velocity‑sensitive resonant VCF. Pressing both buttons turns the sound into all the above, with the VCF being modulated by a sample‑and‑hold LFO signal. Some of the ROM Sounds use quite extreme variations, occasionally introducing completely different sounds, while others utilise the buttons to select which effects buss a sound is sent to. When used with Kit Sounds, the buttons normally reverse a wave or introduce a filter effect. A nice additional feature is that in Track mode the Patch Selects layers become editable, MIDI controllable and recordable via the sequencer. It's surprising how expressive a couple of oval buttons can be!

Effects Algorithms


  • Parametric EQ
  • Hall Reverb
  • Large Room
  • Small Room
  • Large Plate
  • Small Plate
  • NonLinReverb1
  • NonLinReverb2
  • Gated Reverb
  • Stereo Chorus
  • 8‑VoiceChorus
  • Reverb‑Chorus
  • Reverb‑Flanger
  • Reverb‑Phaser
  • Chorus‑Reverb
  • Flanger‑Reverb
  • Phaser‑Reverb
  • EQ‑Reverb
  • Spinner‑Reverb
  • DDL‑Chorus
  • DDL‑Flanger
  • DDL‑Phaser
  • DDL‑EQ
  • Multi‑Tap DDL
  • Distortion‑Chorus
  • Distortion‑Flanger
  • Distortion‑Phaser
  • Distortion‑Auto Wah
  • ResonantVCF‑DDL
  • Distortion‑VCF‑DDL
  • Pitch Detuner
  • Chatter Box
  • Formant Morph
  • Rotary Speaker
  • Tunable Speaker
  • Guitar Amp
  • Distortion‑DDL‑Trem
  • Comp‑Dist‑DDL
  • EQ‑Comp‑Gate
  • EQ‑Chorus‑DDL


  • Smooth Plate
  • Large Hall
  • Small Hall
  • Big Room
  • Small Room
  • Reflections
  • Bright
  • Huge Place

Urban Dance Project Expansion Board

Although there are other MR‑EXP Wave expansion boards available, and more in the pipeline, the 24Mb MR‑EXP3 Urban Dance Project board was supplied with the review ASRX, and it's a stonker! It contains over 500 sounds and 400 waves, some splendid drum kits (including 40 or so GM Kits), sample loops, grooves, layered pads, hits, basses, synths and sound effects. As you can imagine, with this many sounds I couldn't begin to list them, but I must say that this is an outstanding collection of superb and essential dance sounds. A recommended purchase for any ASRX owner.


SoundFinder is a database of all the sounds in the ASRX. It allows you to view and search for sounds in various ways, using the SoundType and SoundName control knobs. Basic classification categories include instrument type or family, location in memory, ROM or RAM number and alphabetical order. It's also possible to rename, re‑categorise and set your own criteria for inclusion in a list. The SoundFinder really comes into its own when one of the MR‑EX expansion boards is fitted, and makes it very easy to find a particular type of sound relatively quickly.

Expansion Options

  • ROM expandable to 26Mb using MR‑EXP Wave Expansion Board (£299 including VAT).
  • X8 Audio Output Expander (£199 including VAT).
  • SP5 SCSI Interface (£199 including VAT).
  • RAM expandable to 34Mb using one 72‑pin SIMM socket.

Save & Prosper

As I briefly mentioned elsewhere, the ASRX doesn't have a battery‑backed system RAM; instead the user must save any edited work, no matter how small or trivial, to floppy disk before turning the ASRX off. On the positive side, however, it has a standard, DOS‑format, high‑density disk drive and quite happily uses DOS disks formatted on PCs or Macs. What this means in real terms is that any new samples, Sounds, Kits, effects, sequences or changes to the system setup are placed into temporary RAM categories. From the DISK/SAVE pages, you have the option of using SYSTEMSETUP, to save MIDI channels, sampling settings, metronome level and various system settings; ALL‑SESSION, to save everything in RAM, including Kits, Sounds, sample setup, sequences and system); or ALL‑SOUNDS, to save all RAM samples, including those copied from ROM as part of a Kit. You can also save individual sequences as MIDI files and samples as AIFF files, both of which can be loaded into and read by many PC or Mac programs. A useful feature is that the ASRX will also load standard PC‑type WAV audio files, although it does convert them to AIFF when loading and saving.

When saving a session, the ASRX is very helpful and performs a little check‑up routine before informing you exactly how many floppy disks you will need to save your work onto. If there are any particularly long samples, it will divide them up across as many disks as necessary and then reconstruct the samples when you reload them. The fact that system and performance data isn't retained at power‑down isn't the end of the world, but it does slow things down a bit, particularly when you're using the fairly slow floppy disk drive. You can save your preferred system setup to floppy as an auto boot disk, but unfortunately the ASRX won't auto‑load Sounds, Kits and samples. A solution for the forgetful RAM problem would be for Ensoniq to give the ASRX a non‑volatile system RAM. In the meantime, though, investing in the optional SCSI upgrade and something like a Zip drive would be the best bet, and would considerably speed up saving and loading, particularly if you have more than the base memory installed.

Low Flying Oscillators

I've always been a fan of LFOs; they're an often‑neglected element in the arsenal of parts used to influence electronically produced sound. From soft vibrato to hard‑edged trills, from a sweeping pan to a super‑fast arpeggio, somewhere along the line there's an LFO. And I like the LFOs in the ASRX a lot. The Kit Sounds, Standard Sounds and Effects each use very comprehensive and complex LFOs, with various waveforms available, some quite unusual, for a wide range of modulation possibilities (see diagram). All the LFOs have stepped or quantised waveforms specifically for synchronising to the internal sequencer or external MIDI clock signals. The LFO Rate and Rate Modulation can be modulated by other LFOs, S&H, Env 1‑3, velocity, pitch, mod wheel and various MIDI controllers. The stepped LFO waveforms can produce nice arpeggio effects, while the LFO Sync quantising is adjustable from whole note to 32nd‑note triplets, useful for syncopated modulations. I've only scratched the surface of the many parameters available for editing the LFOs, but I hope I've given you a taste of what is possible.


  • Resampling.
  • Tons of features.
  • Fast and easy to use.
  • Expressive filters.
  • Responsive pads.
  • Sturdy construction.
  • Expandability.
  • AIFF, WAV, MIDI file and DOS compatibility.
  • Can save large samples across multiple floppy disks.
  • Good value for money.


  • Volatile system RAM.
  • Small LCD.
  • Not enough dedicated sequencer buttons.
  • Base unit needs more RAM and ROM voices.
  • ROM sounds and kits a little uninspiring.
  • No play while load.
  • Slow disk drive.
  • Can't read Akai disks.


A fully featured sampling workstation with a great sound, a versatile sequencer, pro effects, responsive pads and straightforward operation. The internal ROM presets are a little uninspiring and the 2Mb RAM is measly, but what sets the ASRX apart from the competition is the resampling feature, which, with enough RAM, makes the machine a joy to use.