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Emu E4XT Ultra

Emu E4XT Ultra

Is it a synth, a sequencer or a sampler? The answer to all three questions is an emphatic 'yes', as Paul White finds out when he takes the E4XT Ultra into his studio.

The E4XT Ultra is Emu's latest 'big guns' sampler, the top of the E4 Ultra range and directly competing with Akai's recent top‑of‑the‑range S6000 in terms of market position. At the heart of the Ultra is a new 32‑bit RISC processor designed to tighten up MIDI timing and SCSI operation, as well as facilitating SMIDI sample transfer. E4XT Ultra facilities include 128‑voice polyphony and 32‑part multitimbrality as standard, plus eight outputs, including the main left/right stereo outputs. This number can be expanded to 16 analogue outs if you desire, or eight digital ins and 16 digital outs on an ADAT‑format I/O option if you prefer to expand digitally (see separate box elsewhere in this review for a list of some of the expansion options). There's also a 3.2Gb internal hard drive fitted as standard, though a larger drive of up to 9Gb can be fitted, and SCSI for connecting external drives (up to 18Gb, including DVD — Digital Versatile Disc — drives). Memory expansion is by means of regular SIMMs or Flash memory (see the 'Thanks For The Memory' box). A maximum of three ROM SIMMs, similar to those used in the Proteus 2000 synth module, can also be added for non‑volatile onboard sounds (to a total of 96Mb of ROM, quite independent from the maximum 128Mb of sample RAM the Ultra XT has at its disposal).

All this gives the E4XT Ultra all the functionality and immediacy of a hardware synth, and it certainly has the trappings of one — the available filter fire‑power is seriously impressive (see the 'Filtering Through' box) and there are even onboard effects; the built‑in dual processor offers 76 types, including the obligatory chorus and reverb, and numerous effect routing possibilities are available in multitimbral mode. Sounds may also be resampled with effects.

Based around Emu's EOS (Emulator Operating Software), which is used in a number of other Emu instruments, the 3U rackmounting Ultra XT utilises a computer‑style graphic user interface, based on files within folders. Conceptually, the E4XT Ultra is structured much like a traditional modular synthesizer, but without the modules! Samples or optional ROM waveforms act as the oscillators, and the operating software provides virtual patchcords, envelopes, LFOs and filters. Emu have always been keen on modulation, and in the Ultra, any of 65 modulation sources can be routed to a choice of 67 destinations using 24 'virtual' patch cables per voice. The modulation sources include two multi‑waveform LFOs per MIDI channel, direct MIDI parameter control over just about everything it makes sense to control, and three comprehensive envelope generators per voice.

As standard, the E4XT Ultra has 64Mb of sample RAM fitted. However, since using anything other than a fully stuffed machine would be false economy in light of today's RAM prices, many buyers will surely add more, to the maximum 128Mb RAM capacity. Samples can be read in EIV, e64, EIII, EIIIX and ESi library formats, but the Ultra is also able to load in Emax II, Akai S1000/S1100/S3000 and Roland S760 samples. WAV files may also be imported via a PC‑formatted HD floppy, though I couldn't get the machine to recognise WAV files on CD‑ROM. This is a bit of a shortcoming when you consider how many inexpensive sample CD‑ROMs containing WAV files are now available. User samples may be recorded via the analogue inputs (which feature 20‑bit delta‑sigma converters for a sensibly low noise floor) at sample rates of 22.05kHz and 44.1kHz. Sampling in the digital domain can be at 32kHz, 44.1kHz or 48kHz.

The Tour

The front panel of the E4XT Ultra is very much 'old‑school' Emu. A large LCD window sits in the centre of the panel, and all the control buttons are located within the lower half of the panel. There's a large data‑entry wheel to the right of the window, and a floppy drive slot at the extreme right‑hand side of the machine.

The E4XT Ultra's functions are divided into six main groups (Sample Manage, Sample Edit, Preset Manage, Preset Edit, Master, and Disk) accessed via the Module Select keys. An Audition key enables samples to be played directly from the front panel, and new samples may be loaded in the background via Emu's established SoundSprint technology. Three assignable keys allow the user to create direct links to any menu screen.

The front panel, with the six main soft buttons.The front panel, with the six main soft buttons.

Beneath the LCD are six function buttons (F1-F6) that generally relate to whatever functions are displayed on the screen above them. The remaining keys are used mainly to navigate around the operating system, though there is a set of numeric keys for direct parameter entry. Values may also be changed using the data‑entry wheel or, for fine adjustment, the Inc/Dec keys.

The rear of the E4XT Ultra has the three expansion option port slots (the RAM expansion slots, unsurprisingly, are inside the case, as is the single PCI slot for the RFX option, of which more shortly). The back panel also sports a 50‑pin Centronics SCSI interface, two complete sets of MIDI In, Out and Thru connections to address the machine's 32 parts, AES/EBU digital I/O, and word clock in and out on BNC connectors. The two analogue mic/line inputs and eight analogue line outputs (including the main stereo outputs) are all on balanced jacks, with input gain adjustable from within the software. A further socket allows the connection of a standard PC AT ASCII keyboard for data entry, which is most welcome when naming samples. A small, reasonably quiet cooling fan is located above the mains inlet.Emu E4XT Ultra rear panel connections.Emu E4XT Ultra rear panel connections.

EMU Operating System

Getting to know the E4XT Ultra means becoming acquainted with the EOS operating software. The latest version, EOS 4.01, sorts out some minor routing bugs that occasionally popped up in v4.0. During my tests, it appeared stable and didn't do anything unexpected, but because software has so many dark and hidden corners I wouldn't be so foolhardy as to proclaim it flawless.

EOS arranges samples, voices and Presets (the last comprising one or more voices, complete with key‑mapping, envelope, filter and modulation parameters) into banks, and banks may contain multisets of Presets for sequencer use, or sets of single Presets for sequential selection in live performance. Voices are edited as part of a Preset and can be copied to new Presets if desired. Up to 1000 samples per bank may be stored, deployed in up to 1000 Presets, so the only practical limitation on how much material you can load in at once is the amount of sample memory fitted. The EOS SoundSprint function may be used to browse presets from the hard drive in the background while another sound is playing, which cuts out a lot of waiting for sounds to load up. Up to 10 SoundSprint Presets can be loaded at any one time; if you load in an eleventh the oldest is discarded. In addition to handling sampling functions, EOS also includes a 48‑track sequencer/MIDI data filer (see the 'Track Event' box).

During voice editing, the synth‑like part of the processing chain is defined using the virtual patchcords mentioned earlier. Virtual patching isn't a new concept by any means, but having this degree of flexibility in what is ostensibly a sampler makes the E4XT Ultra very powerful. The default condition is that half a dozen patchcords are pre‑defined to create the traditional model of a basic synth, where the oscillator feeds through an envelope‑controlled filter and a level envelope. However, more patchcords may be added to create the kind of voice complexity you'd expect on a modular synth; the patching system can include 'arithmetic modifiers' to restructure the data in real time during performance, just as with a big modular system, but you need to have a good grasp of the way modular synths work and their capabilities to make full use of this. Those not used to this way of working might benefit from a pencil and paper, but most of the time it's about deciding what modulates what and by how much. In fact, this whole review could be taken up exploring the ramifications of patching and arithmetic modifiers but, sadly, there's no way I can cover all the fine detail of a product that comes with a 418‑page manual just for the operating system! Fortunately, the manual does feature a number of blow‑by‑blow practical sessions that you can work through if you're new to sampling.

Emu E4XT Ultra

Sampling in general can be fiddly and time‑consuming, especially when you're having to create multisamples and loops. EOS does its best to help by enabling samples to be automatically truncated, looped and normalised directly after sampling, and it can even help with keyboard mapping. There's also a powerful suite of tools for looping and combining samples, plus tools for time and pitch manipulation, and a selection of creative effects. These include a licensed implementation of the Aphex Aural Exciter, bit‑rate reduction (for grunging up sounds), a means of merging two files so that only frequencies common to both appear, and even a phase‑linear filter for adding EQ without phase shift — important if you're only EQ'ing part of a sample and don't want to end up with glitches where the treated and untreated sections join.

Finally, there's the 'Beat Munger', for restructuring drum loops in real time. Beat Munger turns out to be a lot of fun, as it doesn't just slice and dice loops but also time‑stretches the resulting segments so that you're not left with any unnatural gaps. Various parameters are adjustable, so it's possible to turn the time‑stretching artifacts into full‑blown effects, and you can also alter the loop length or omit segments to create new rhythms. Individual beats may be removed, and quantising can be either straight or in various swing times. These facilities should appeal especially to dance artists and remixers.

The display crams a lot of information into a small space, but thanks to the well‑thought‑out operating system, sample creation and file management are always straightforward.The display crams a lot of information into a small space, but thanks to the well‑thought‑out operating system, sample creation and file management are always straightforward.

Routing & Effects

The E4XT Ultra's two effects processors are dubbed A and B. A handles the 44 reverb and delay effects, while B looks after 32 modulation and distortion treatments. Each effect has just three adjustable parameters, so editing needn't be hard work. If you're starting to think this sounds rather familiar, that's because the effects and routing structure is very similar to that of the Proteus 2000, reviewed back in March of this year, although, unlike the 2000, the Ultra doesn't have the provision to patch in external effects, because all its outputs are balanced

The effects are closely linked with the signal routing to the various outputs, and the system is configured with four effects busses: Main, Sub 1, Sub 2 and Sub 3. Each voice or MIDI channel can be routed to one of the four busses and each of the effects processors has a variable send level sourced from each of the busses. At Preset level you can program whatever effects setup you like, but in Multi mode the fact that there are only two effects processors shared between up to 32 different parts means that the Preset effects designation can't be maintained.

As with many multitimbral synths and samplers, the effects routing is a compromise in multitimbral mode, but Emu have offered a number of options so that each user can pick the way that works best for them. Inevitably, this can make the effects routing seem quite complicated initially, though there are block diagrams that make life easier. One option is to have the global effects setup follow the setting contained in whatever Preset is called up on a specific MIDI channel. Alternatively, a global effects setup can be chosen that will apply to all parts. However, you don't have to have the same amount of effect on all the parts in a Multi, because the four sets of busses and sends allow four different effect balances to be set up, based on the two effects processors: you might have one level of reverb on the Main buss, a lesser amount on Sub 1, a mix of reverb and another effect on Sub 2, and a different mix of reverb and effect on Sub 3. This is a different approach to having discrete effects send controls on each part of a Multi, but it is very flexible. It's also possible to program the effects such that effect A feeds into effect B if required. If nothing is plugged into the Subs, all the dry plus effect signals appear at the main stereo output.

Ultimately, the only entirely satisfactory solution is to have a separate effects section for each of the 32 multitimbral parts, and this may not be as far away as it seems. Emu have developed something called the R‑chip, which will become the basis of a PCI expander card, the RFX board, providing up to 32 simultaneous effects that can be assigned in different ways. I don't have any further details on this yet, but Emu have it slated for release early next year.

Using The Ultra

As a long‑time Akai user, I initially found the organisation of the Ultra a little confusing, but it doesn't take too long to find your way around the basics. Once you grasp the sample/voice/Preset/bank hierarchy, it all starts to make sense. In addition, the navigation system is generally easy, as appropriate labels appear above the six function buttons according to what you're doing. When I set about creating my own samples, I found it remarkably easy, even when looping manually.

The actual sample‑recording procedure is very similar to that of any other serious sampler, with the option to trigger recording via signal level where appropriate. You then set the record time and activate the sound source to be sampled. If the automatic truncate, looping and normalise functions are active, these processes take place as soon as the sample has been recorded. However, I prefer to choose my loops manually. A small but clear waveform display shows you what you've recorded, and movable start and end markers are used for manual truncation. The system supports a single sample loop, with either loop in release or 'play the rest of the sample after release' options, and there are various tools to make looping easier, including level compression. A Correlate button tries to ensure that the waveforms are at least in phase at the loop point and, as with truncation, the loop‑point marker can be dragged around to find the best‑sounding place. Chances are that even when you've made the best possible loop of a sustained sound there will be an audible glitch, but after the loop has been OK'd a crossfade dialogue box comes up, allowing you to set a crossfade time to cover the join. The original waveform is kept intact, allowing one level of Undo. It's generally best to keep the loop time as short as possible, to avoid phasiness at the crossfade point.

Once samples have been recorded and looped they're mapped on to the keyboard. As mentioned earlier, the Ultra helps out here by spreading individual samples out around half an octave either side of the original note — you have to tell the machine what note you've just sampled. Out‑of‑tune samples can be retuned at either the sample‑ or voice‑edit levels, and it's also possible to transpose samples. The user can adjust placement of samples on the keyboard, after which filter and envelope assignments (and quite a lot else) may be made, to create a voice. Multiple voices can be used within each Preset, and it's also possible to link a Preset to another (rather like the original Proteus) so that when the first is called up, both play together. You can arrange Presets as layers, keyboard splits and so on, and Global Preset parameters can be set up to provide input from eight specified MIDI controllers, in addition to such preassigned controllers as MIDI volume, panning, modulation, pitch‑bend, sustain, footpedals, expression, and breath control. Effects are also set up at Preset level and the Ultra allows a number of keyboard note assignment modes to be defined, so that it's possible to emulate the keyboard behaviour of many classic monophonic and polyphonic synths.

Though the Ultra features a comprehensive arpeggiator, just to underline the fact that it's a synth as well as a sampler, there's also a range of stepped LFO waveforms that can be used to modulate the oscillator pitch in a musical way. In effect, each stepped LFO waveform creates a mini arpeggio from a single note.

Incidentally, I was most impressed by the E4XT's ability to transpose a sound down by several octaves without it being wrecked by quantisation distortion. This ability is shared by other Emu samplers and is made possible by the company's proprietary G chip (their chip handles the clever filtering, and the R chip is on the way, so does this mean that we can expect 23 others?). Though I don't have full details of how the G Chip works, other than that it uses clever interpolation, it seems to work amazingly well.

Emu E4XT Ultra viewed from the front.


I've been using the E4XT Ultra on and off for several days now, and though I can find my way around all the regular functions I feel it would be a long time before I could honestly say I knew it properly. That's not a criticism of the machine — it's just that there's so much to get to know. It's rather like working with a computer sequencer: pretty quick to learn what you need to get started, with other facilities coming to the fore as you realise you need them.

I like the computer‑style user interface and the way in which the on‑screen labels always tell you what the six function buttons will do. Setting up single samples or simple multisamples is pretty intuitive, and voice editing is also reasonably straightforward — if you need to make a change to all the samples within a keyboard multisample, you can do it globally rather than having to adjust each individual sample.

The sequencer (see the 'Track Event' box if you haven't already) may be basic by computer standards, but it's still powerful enough to use as a main sequencer and should suit those used to hardware devices. It's also very useful for sequence playback in live situations where taking a computer would be less practical. SoundSprint is a great idea for browsing samples, and some of the sound‑mangling tools provided as standard are quite spectacular. The signal routing side of the E4XT Ultra is also immensely flexible, though I'll admit that I found it a little confusing to decide on the best effects option to use when operating multitimbrally. Hopefully, the forthcoming RFX option should resolve those restrictions.

Ultimately, the E4XT Ultra is so much more than a sampler, which is why it can seem complex to those brought up on more focused sampling products. The synth side of the machine is remarkable, especially in its ability to emulate modular systems, and those sequenced vowel morphing filters can literally make harmonically rich samples talk. Having the ability to keep frequently used sounds in flash memory is a great advantage to live performers, while the sound ROM expansion provides synth‑like immediacy. In some ways it would have been useful to have had a good GM set built in as standard, on ROM, simply for playback of those MIDI sequence files, but I know how much Emu have resisted what they obviously see as the creeping blandness of GM. Nevertheless, a high‑quality GM ROM sound set is planned for Proteus 2000, so maybe that set will eventually be available for the E4XT Ultra as well?

Before closing, I'll have to apologise for all the clever stuff that didn't get mentioned here, because just about every page of this machine's manual introduces a new and useful snippet of information. The mental investment in getting the most out of the E4XT Ultra is probably comparable with learning a good sequencer, but then the rewards are probably in similar proportion too. This is most definitely a machine to grow up with, not to grow out of.

E4XT Ultra: Brief Specification

  • 128‑voice Polyphony.
  • 32‑part multitimbrality (2 sets of MIDI connections).
  • 64Mb RAM.
  • 3.2Gb Hard Drive.
  • Dual 24‑bit effects processors.
  • 21 filter types.
  • 8 Balanced analogue outputs.
  • Word clock & AES/EBU I/O.
  • 240 x 64‑dot Custom Backlit Display.
  • 48‑track sequencer.
  • Arpeggiator.
  • 9 bundled CD‑ROMs (over 2Gb of sounds); PC/Mac editing software.

Selected E4 Ultra XT Expansion Options

  • 6871 Orbit/ Phatt Sessions 16Mb Sound ROM: 500 funky/electronica presets, including all the samples from the Emu Orbit and Planet Phatt sound modules.
  • 6864 R‑Chip 32‑Channel Studio Effects Processor: adds 32‑channel R‑Chip Studio Effects Processor to E4 Ultra (not available until the New Year).
  • 6876 16Mb Flash Memory.
  • 6877 32Mb Flash Memory.
  • 6313 (Analogue Output Expander): expands E4 Ultra's balanced analogue outputs from eight to 16.
  • 6861 8‑in/16‑out ADAT card.

Track Event: The Sequencer

The onboard sequencer isn't as comprehensive as something like Cubase or Logic, but it does offer all the essentials. It can also be used to play back format 0 and 1 standard MIDI files, which may then be merged into whatever bank contains the necessary sounds — probably a suitable GM bank in the case of commercial MIDI file disks. I checked this function using commercial MIDI files and got it to go first time, once I'd copied my MIDI files onto an HD floppy (the disk drive didn't seem happy with old double‑density floppies). There's also a Jukebox function for playing several sequences in order, which is useful for live performance, as is the fact that the sequencer can play internal or external sounds. Sequences are stored either within sound banks or in their own bank, and can also be saved to disk in EOS format or SMF (Standard MIDI File) format.

Though the onboard sequencer only looks at the outside world via a relatively small LCD window, it's actually quite a lot more powerful than it might at first appear. It can record up to 48 tracks, which can be quantised either during record or after recording (with quantise strength and swing‑type variations), and in the edit department it can handle the full range of cut/copy/paste functions. MIDI sync is supported, it's possible to erase control data independently of notes, there's one level of Undo to help save you from disaster, and tools are provided for changing sequence data velocity and transposition.

I have to admit that I found the sequencer rather slow to use after a computer sequencer, but it seemed to cope with everything I asked it to do as I pushed buttons with one hand and held the manual with the other. Those players who need to do less editing than me would probably find it quite easy to get used to, but I'll stick with my Mac! It's worth bearing in mind that because both internal and external sounds can be sequenced, and because the sequencer can lock to an external MIDI clock (but apparently not MTC), the E4XT Ultra could easily meet all the sequencing requirements of a live performance.

Filtering Through

In all, there are 21 filter types available on the Ultra, based on the Z‑plane technology first aired in Emu's own Morpheus, and though most are structured to emulate classic analogue synth‑type filters, with 12, 24 and 36dB/octave slopes in low‑pass, band‑pass and high‑pass versions, there are also more esoteric variations. These include morphing filters, phaser/flanger filters, a contrary band‑pass (fancy name for notch?) and three different morphing swept EQ filters.

EMU Extras

The E4XT Ultra comes bundled with nine sample CD‑ROMs from the Emu sound library and a customised version of Emagic's SoundDiver editing/librarian package for both Mac and PC. Also provided is EOSLINK, an onscreen remote control panel, again for both Mac and PC. These extras are very worthwhile, but I can't help thinking that an instrument as complex as the E4XT Ultra deserves a monitor output and built‑in editing software. Similarly, I feel there should have been a CD‑ROM drive built in as standard: both Akai and Emu samplers have a history of being very fussy as regards the type of external CD‑ROM drive they're used with, and sample CD‑ROM libraries are so important these days.

Thanks For The Memory

One potentially confusing aspect of this sampler is that the memory is divided up such that some is dedicated to storing samples, while another section of RAM on the motherboard stores Preset and sequence data. In addition, as mentioned earlier, ROM and flash memory can be fitted. What is the difference between the different types? Well, ordinary sample RAM (of which, as already mentioned, the Ultra XT can have up to 128Mb) is used to store newly created samples or those loaded in from hard disk or CD‑ROM; sample ROM contains read‑only sounds and is optional; and flash memory is a type of RAM that doesn't lose its contents when the power is removed, making it ideal for storing sounds or data that you would like to be able to access without first having to load from disk. Flash memory is significantly more expensive than regular RAM, and must be purchased as an expansion option, but it is completely separate from the ordinary sample RAM (so you could fill the XT Ultra to its maximum 128Mb and still add Flash memory).


  • Combines the attributes of a powerful sampler with onboard sequencing and advanced synthesis.
  • 128‑voice polyphony.
  • Excellent sound quality with a very versatile filter section.


  • Effects routing in Multi mode can be initially confusing.
  • A machine of this complexity would benefit from a video monitor output, though a version of Sound Diver is bundled for those who prefer computer editing.
  • No integral CD‑ROM drive.


The E4XT Ultra is an immensely powerful sampler/synth/sequencer that comes with a useful armoury of sound processing and performance tools. It will take a long time to get to know it thoroughly, but routine sampling is very straightforward.


£2799 including VAT.