Magazine Archive

Home -> Magazines -> Issues -> Articles in this issue -> View

Ensoniq EPS

Performance Sampler

It's been a while in the pipeline but Ensoniq's successor to their popular Mirage sampler is up and running. Simon Trask checks out the latest "peoples' sampler".

Ensoniq's new sampler is up against stiff competition in a crowded market. Has the EPS got what it takes to be more than a Mirage?

SAMPLING DEVOTEES HAVE a lot to thank Ensoniq for. When the company unleashed their Mirage eight-bit keyboard sampler back in 1985, they took sampling out of the hands of the musical elite and placed it in the grubby paws of the masses. Together with Akai's sonically superior but otherwise less sophisticated S612 rack-mount sampler, the Mirage did much to popularise the concept of sampling. Little did anyone realise where it would all lead.

But just as the Mirage changed people's expectations in its day, so the steady flow of sub-£2000 samplers which inevitably followed on its heels have succeeded in outclassing Ensoniq's sampler in virtually every respect. Despite the company's worthy attempts at updating the original Mirage, hardware architecture ultimately determines a point beyond which an instrument will not go. Cue the Ensoniq Performance Sampler.


LIKE ENSONIQ'S RECENT SQ80 synth, the EPS comes fitted with the company's custom-designed 61-key, Poly-Key keyboard, so called because in addition to attack velocity it is responsive to polyphonic aftertouch. The keyboard, with its strange "clackety-clack" feel, isn't the EPS' most endearing feature. Still, you do get a choice of 16 keyboard response curves ranging from soft to hard.

And so to some figures (sampling always seems to involve lots of numbers, one way or another). Sampling (monophonic) and sample playback are both 13-bit linear, sample storage is 16-bit and sample processing (for instance, filtering) is 24-bit. There are 40 user-selectable sampling rates, ranging from 6.25kHz to 52.1kHz. The EPS employs fixed-rate sample playback, a fact which shows in the improved quality of samples played back at lower than their original pitch. You get a choice of three playback rates based on how many voices you want to use: 31.2kHz gives you 20 voices, 39kHz gives you 16 voices, and 52kHz gives you 12 voices. The EPS' sound quality is impressively clear, sharp and bright, with plenty of presence. The sampler's capabilities are well illustrated by the nine Essential Sound Disks which come with the instrument. Apparently the range of samples contained on these disks was determined by the results of a world-wide survey conducted by Ensoniq, which found that the most used sounds were, in order of importance, grand piano, string section, brass section, bass, drum kit, vocal pad, sax, synth, electric guitar and acoustic guitar.

The EPS comes with 512Kbytes of internal memory. Bearing in mind that Ensoniq's new sampler stores its samples in 16-bit format, that's 256Kwords (a word = two bytes) or enough memory for 8.6 seconds of sampling at a 30kHz sample rate. Ensoniq produce one memory upgrade, the ME1, which doubles the internal memory to 512Kwords. The company had originally intended to produce a quadruple memory upgrade, too. However, this has been shelved, at least until next year, as the high price of memory chips in the US would have made it prohibitively expensive. Latest news is that some third-party European companies (German company PA Decoder being one of them) are working on larger memory upgrades which should be available at a more affordable price.

As with the company's ESQ1 and SQ80 synths, the EPS has an onboard eight-track sequencer. In fact, ESQ/SQ owners will find a lot that's familiar in this department. However, there's one significant difference between the EPS and its companions: the sampler dynamically allocates its memory to samples and sequences - to put it bluntly: you trade off one against the other.

Look at it this way: the complete 256Kword memory allows upwards of 80,000 notes (pre controllers). Using a quarter of the memory for sequencing still gives you 20,000 notes, a reasonable figure unless you're controller-mad. Double the internal memory and you've got 15 seconds of sampling at 30kHz in addition to your 20,000-note sequencing capacity. Or you could have less sampling time and more notes.

You can also use the EPS as a MIDI SysEx recorder, with the entire EPS memory being turned over to this function when you select it. However, it will only operate with instruments which can initiate their own SysEx data dumps, and you have to save one data dump at a time to EPS disk - you can't "chain" dumps from several instruments into a single file for convenience.

Sample data can be transferred via MIDI, as can all EPS parameters (in fact, parameter adjustments are sent over MIDI in real-time as SysEx messages). However, there is no facility for bulk-dumping sample and parameter data from the EPS - it has to be pulled out of the sampler from an external program. Nor does the EPS employ the MIDI Sample Dump Standard. Basically, you need either dedicated EPS editing software or a generic sample-editing program - in the latter category, Alchemy and Universal Sound Designer are both EPS-compatible, allowing remote sample editing and interchange of samples between different samplers.

Disks and Intonation

THE EPS' ONBOARD disk-drive (complete with moulded shelf for stacking your disks on) uses 3.5" DSDD floppies capable of holding 800Kbytes, or 1600 Blocks, of sample data. The sampler has its "operating system" stored on disk as opposed to inside the sampler on ROM. This approach (which Ensoniq pioneered on the Mirage) is slowly catching on as manufacturers begin to realise the advantages of making their instruments as open-ended as possible. For one thing, installing software upgrades is as easy as loading in a new disk. The EPS allows you to make disk copies of the OS, so you shouldn't need to worry about corrupted disks or about leaving that one vital disk at home. The sampler occasionally requires OS software routines off disk; it will automatically load them if an OS disk is in the drive, but otherwise will prompt you to insert one. In fact, it could be worth using an OS disk as your current work disk, or the first sound disk of your set (inevitably at the expense of some disk space).

Mirage owners tempted to upgrade to the EPS but loath to lose their sample library can let out a cheer at this point. Ensoniq have done the sensible thing and allowed Mirage samples to be loaded into the EPS and converted into EPS Instruments. Loop points are retained, but you'll have to set up new filter and amplitude envelopes - a small price to pay. All you have to do is insert a Mirage disk into the EPS' disk drive, select the appropriate routine and let the EPS do the rest. You can then save the sample(s) to EPS disk as an Instrument. This process works very smoothly, with samples benefiting from the clarity of the EPS.

The EPS' most trumpeted feature is its ability to load samples while you play on the keyboard. This works well, even allowing you to switch sounds during loading. Of course you need to pre-plan what samples will fit in the EPS' memory - it's no use trying to load a sample and finding that there's no room for it.

"Mirage owners tempted to upgrade to the EPS can let out a cheer - Ensoniq have allowed Mirage samples to be loaded into the EPS and converted into EPS Instruments."

The sampler also allows you to play the keyboard while a sound is being saved to disk. Unfortunately, Ensoniq haven't extended this principle to other disk operations such as formatting (which takes a lengthy 80 seconds) and loading sequence data.

Intonation fans should definitely check out the EPS. You can define a pitch intonation table for each Instrument which allows you to specify coarse (semitone resolution) and fine (one-cent resolution) tuning for every note in the MIDI range (0-127/A0-C8). In addition, a feature known as "extrapolation" allows you to reproduce the pitch sequence of any range of notes (even a single interval) across the entire MIDI note range - making it an easy way of creating, say, a quarter-tone scale.

Sampling and Organisation

THE EPS ORGANISES its sample data in the following way. Up to eight Instruments can be held in memory at the same time; these are assigned to the eight Instrument/Track buttons beneath the central fluorescent display. Each Instrument can consist of up to 127 Wavesamples (actual sample data), which can be organised across the entire MIDI note range in up to eight Layers.

Each Layer can only play one Wavesample per note, so although you can set a "note range" amplitude envelope for each Wavesample (complete with fade-in and fade-out specified by MIDI note numbers) you'll have to use samples in different Layers if you want to create proper keyboard crossfades. Once you get the hang of the necessary procedure it's quite straightforward, if a little laborious.

Velocity crossfading between Layers is also possible, as is velocity switching. Each Layer within an Instrument can be given its own velocity window, so you can layer and switch between any combination of samples.

The sampling process itself is fairly straightforward. Select the required Layer and Wavesample and then press Sample. This takes you into level-detect mode, where you an set the sample rate, the cutoff frequency of the antialiasing filter, pre-trigger time (0-127 milliseconds) and input level (mic/line). There's also a display of available sampling time, but you can't actually predefine sample duration - the EPS carries on sampling until it runs out of memory or until you hit the Cancel button or footswitch. Fortunately there are also commands available for trimming sample start and end points.

The EPS provides you with a peak-level meter display, with threshold and overload indicators. You initiate sampling by pressing the Enter button or the footswitch (though with threshold set above zero it's effectively the input signal which initiates sampling). The EPS automatically assumes that you want to take a new sample, but you an easily redo a sample by reselecting the appropriate Wavesample.

Once you've taken your sample the first thing you're asked to do is assign it a root key - the note on which the sample will play back at its original pitch. You can also fine-tune individual Wavesamples to cent resolution, an essential feature if you're interested in syncing-up sampled rhythm patterns.

The first sample on the keyboard will spread in either direction across the entire MIDI range. When you add further samples, the EPS automatically sets the "splitpoint" to midway between each pair of adjacent root notes. Creating a complete Instrument is a fairly straightforward process once you understand how it's structured.

Each Wavesample can be put through three five-stage envelopes - "hardwired" to pitch, filter and amplitude - and a single LFO. You can define two shapes for each envelope, one for maximum velocity and one for minimum velocity; the EPS smoothly interpolates between the two as you play. Also included are second-release time and level parameters, which will be familiar to SQ80 users as a sort of pseudo-reverb.

"The EPS' most trumpeted feature is its ability to load samples while you play on the keyboard. This even allows you to switch sounds during loading."

The EPS provides you with several preset envelopes if you want to get straight into looping without bothering to define your own. Ensoniq haven't shortcut on looping options, with crossfade loop, reverse crossfade loop, ensemble crossfade, bowtie crossfade, bi-directional crossfade and synthesised loop options. With Auto Loop Find set to on, the EPS will pick what it considers to be optimised loop points each time you move the loop start and end values. Ensoniq are to be congratulated for providing so many options, but they still don't represent an automatic passport to looping heaven - looping samples is an art which has to be learnt from experience.

Other handy features include Convert Sample Rate, Normalise Gain, Volume Smoothing, the ability to mix, merge (crossfade) and splice Wavesamples, and the ability to copy Wavesamples into different Layers within an Instrument - but not across Instruments - without copying the actual data (thus saving on memory). An easy way of fattening up a sample is to copy it into one or more Layers and detune it.

Batches, Instruments & MIDI

ENSONIQ SET GREAT store by performance-oriented features, as you might have guessed by now. One such feature is Patch, which is a programmable combination of Layers. Each Instrument can be assigned four Patches, these being called up from a pair of non-latching dedicated buttons above the pitch and mod wheels, or - for handsfree operation - from a footswitch plugged into the EPS' rear panel (you'll need Ensoniq's SW5 dual footswitch to select any of the four Patches).

The idea here is that you an quickly switch between variations of a particular sound so as to introduce more natural inflections during performance, but in practice the applications are wide open. The hackneyed phrase "limited only by your imagination" comes to mind - to which "limited also by available memory" might be a useful qualification. The flexibility of the EPS' Patches is greatly enhanced by the sampler's voicing algorithm, whereby active voices are never interrupted when you change sounds - a far more musical approach than the cutting short of sounds found on many synths and samplers. The Instruments of the Essential Disk series show off the Patch facility to impressive effect.

An EPS Instrument can consist of several musical instruments split across the keyboard, overlapping and layered in any way you want. For instance, you could have a fretless bass in the lower two octaves (Layer One), strings overlaid with piano in the next two octaves (Layers Two and Three), and tenor saxophone in the top octave velocity-switching between mellow and growling samples (Layers Four and Five). Selecting another Patch within the Instrument could call up a variation on this texture - for instance replacing the fretless bass with a plucked double bass (Layer Six).

Alternatively you could plump for a much simpler Instrument texture and spread your sounds across several Instruments. There's a good reason why you might want to do this (apart from the fact that it could make your life a lot easier). Each Instrument can only transmit on a single MIDI channel (1-16). When you select what Ensoniq term "Smart MIDI Out" mode, each Instrument can be assigned any one MIDI transmit channel (1-16) together with a patch number (sent when the Instrument is selected) and an aftertouch mode (poly or channel). Thus if you wanted to double the fretless bass with another sound via MIDI you would need to put it in a separate Instrument and call both Instruments onto the keyboard. Each Instrument can be given its own keyboard range and transposed in octaves and semitones. Further flexibility is provided by the ability to specify whether an Instrument will play on the EPS only, via MIDI only, or on the EPS and via MIDI.

Selecting a new Instrument automatically "covers up" the previous one where their keyboard ranges overlap. For instance, you could have a multisampled piano covering the entire keyboard, and then, simply by pressing the appropriate Instrument button, call up a double bass sound on top of the lower two octaves. Deselecting the bass sound (by pressing its Instrument button again) "uncovers" the lower two octaves of the piano.

Instruments can also be layered simply by "double-clicking" on the relevant Instrument buttons (click on them again to deselect them). In this way you can have up to eight Instruments on the keyboard at once and layer any combination of them, all with a few button-presses. Automatic recall of a favoured keyboard texture can be accomplished by storing it in one of eight Presets; double-clicking on the appropriate Instrument button then instantly brings that texture onto the keyboard.

Bear in mind, however, that in practice the degree of flexibility is defined by the available memory - and the more memory you use up for sampling the less you have for sequencing. Memory restrictions also apply to another feature of the EPS - though in this case it's disk storage space which imposes practical limitations. The EPS allows you to take a "snapshot" of its current state and save it to disk as a Bank. The idea is that when you next load the Bank, it automatically loads the samples and sequences you had in memory at the time, together with associated parameters, into their correct positions. All this data must be held on one disk, and the disk can't hold as much data as a memory-upgraded EPS. Such is life. Still, if you're prepared to hook up a hard disk (the EPS actually allows you to chain together up to eight hard disks via an add-on SCSI port) you'll no longer have this problem.

"The flexibility of the EPS' Patches is greatly enhanced by the sampler's voicing algorithm, whereby active voices are never interrupted when you change sounds."

For anyone wanting to control the EPS from an external MIDI instrument or sequencer, Ensoniq have provided five MIDI In modes: Omni, Poly, Mono A and B, and Multi. The first two allow you to play a single Instrument, with the EPS responding to all MIDI channels or a single channel.

MIDI Mono reception provides two options. In both cases the EPS receives monophonically on eight consecutive MIDI channels, and independently applies MIDI controller information received on each channel, but, whereas B accesses the eight EPS Instruments, A plays whatever Instruments are currently active on the EPS' keyboard, just as if you were playing the keyboard itself. Both options treat the base channel minus one as a global controllers channel. Meanwhile, in Multi mode each of the EPS' eight Instruments can respond polyphonically on consecutive MIDI channels, with dynamic allocation of the sampler's voices and independent controller response.

The EPS' stereo audio outputs can be augmented by Ensoniq's OEX8 output expander box (£195), which provides a further eight individual outputs. Each Wavesample can be assigned to any one of these extra outputs or to a pan position within the stereo mix, with dynamic polyphonic voice allocation across all outputs. Now that can only be good news for recording musicians.

More irritating is the fact that Ensoniq still can't see fit to provide a separate stereo headphone output - the Left output does double duty as a headphone out, and will only work in stereo if nothing is plugged into the Right/Mono output. So much for quickly setting up sounds on headphones.


THE EPS CAN have up to 80 Sequences in memory at the same time, with each one consisting of up to 999 bars. A Sequence consists of eight Tracks, corresponding to the eight Instrument/Track locations - thus each Track will play whatever sound(s) its Instrument contains. This means that the texture within a Track can be as simple or as complex as you want - always remembering that each Instrument, and therefore each Track, can only transmit on a single MIDI channel. As on Ensoniq's ESQ1 and SQ80 synths, you can decide whether each Track will be internal only, MIDI only, or both internal and MIDI. Where you want the same Instrument on more than one Track, the EPS allows you to copy the Instrument without copying the actual data (both tracks "point at" the same Instrument).

Individual Tracks within a Sequence can be given their own pan (including individual out) and volume settings; alternatively you can choose to retain the individual Wavesample pan settings, which is great for, say, multisampled drum kits. Quantisation can be anything from quarter notes to triplet 64ths, and you can post-quantise any section of a Track. In addition to standard recording, in which existing data is replaced when you rerecord a Track, you can select Add (new data is merged with existing Track data) or Looped (like Add, but with the addition of drum-machine-style continuous looping).

In familiar fashion, the EPS' Sequences can be chained together to form a Song of up to 99 Steps, with as many as 63 repetitions of each Step for those of you who like repetitive music. As each Sequence has its own tempo and time-signature, incorporating such changes into a Song is an easy matter. In addition, for each Song Step you can mute or transpose individual Tracks (though there's only one transpose value per Step), both features helping to economise on sequence memory. Song Steps can be inserted, deleted and edited at any time. Although the EPS can only hold one Song at a time in memory (a rather unnecessary limitation, surely), you could break up the Song chain into several songs by inserting blank or muted Sequences.

Ensoniq have even added a welcome new feature in the form of eight Song Tracks. These are not chained Sequences, but Song-length tracks which you record in - surprise surprise - Song mode. Although it might seem like this feature gives you 16 tracks, there are practical restrictions: each Song Track plays over the same MIDI channel as the corresponding Sequence Track and uses the same Instrument, while controller information affects both Tracks alike. The Song Tracks' real advantage is that they allow you to combine linear-style recording (for those blazing synth solos and fiery percussion workouts) with pattern-based recording.


THE ENSONIQ PERFORMANCE Sampler is an impressive instrument. Clearly a great deal of thought has gone into its design, and the result has real depth. Scarcely an an instrument have been so packed with musically worthwhile features; you're unlikely to exhaust its many possibilities in a hurry.

The "Performance Sampler" tag is well deserved, but the EPS also sits well in a studio context. Once you understand how Ensoniq's sampler works (a process which isn't altogether helped by the accompanying beginners' and advanced manuals, which suffer from lack of clarity, poor structuring and incomplete information) you come to realise that Ensoniq have gone out of their way to make the EPS physically and conceptually easy to use.

Sampling quality is impressive, you get a decent selection of samples with the instrument, and of course you can draw on the already massive library of samples available for the Mirage. The onboard sequencer is both friendly and reasonably powerful, if still ultimately no substitute for the computer-based alternative. And talking of computers, despite its user-friendliness the EPS could benefit from graphics-based editing software. Any takers?

Beneath that mild exterior lurks an instrument which an easily hold its own in the cut-throat world of the sub-£2000 digital sampler. File under "well worth investigating".

Prices EPS £1575; ME1 512K memory expansion board £195, soon to be replaced by the ME1A at £276 (same as the ME1 but with with additional chips for SCSI interfacing); SP1 SCSI port £148; OEX8 eight individual outputs £195. All prices include VAT.

(Contact Details)

Also featuring gear in this article

Ensoniq EPS Update
(MIC Jun 89)

(MT Jun 89)

Browse category: Sampler > Ensoniq

Previous Article in this issue

Casio DG100

Next article in this issue

Age Of Consent

Music Technology - Copyright: Music Maker Publications (UK), Future Publishing.


Music Technology - Oct 1988

Gear in this article:

Sampler > Ensoniq > EPS

Gear Tags:

Polyphonic Aftertouch
16-Bit Sampler

Review by Simon Trask

Previous article in this issue:

> Casio DG100

Next article in this issue:

> Age Of Consent

Help Support The Things You Love

mu:zines is the result of thousands of hours of effort, and will require many thousands more going forward to reach our goals of getting all this content online.

If you value this resource, you can support this project - it really helps!

Donations for May 2021
Issues donated this month: 0

New issues that have been donated or scanned for us this month.

Funds donated this month: £21.00

All donations and support are gratefully appreciated - thank you.

If you're enjoying the site, please consider supporting me to help build this archive...

...with a one time Donation, or a recurring Donation of just £2 a month. It really helps - thank you!

Small Print

Terms of usePrivacy