They stood the world of digital reverb on its head with the MIDIverb, and now Alesis hope to do the same with the MIDIfex, a new budget-price generator of reverb-based special effects. Despite being a preset machine, it sounds more individual than most.

Not long ago, in a review of the Yamaha SPX90 multi-effects processor, I commented on the ease with which equipment designers can now use one set of electronic hardware to perform a variety of different tasks, simply by writing new software.

The Alesis MIDIfex, shown for the first time at June's NAMM show in Chicago, is a prime example of established hardware being put to a different job with the help of new, specially written software. As I understand it, the hardware in the MIDIfex is very similar to that in the same company's MIDIverb, the device that stood the digital reverb market on its head only a matter of months ago.

Certainly, the two machines look very similar, as the MIDIfex is packaged in the same way as its stablemate and features a similar list of available preset patches on its top panel - though the preset names don't always tell the whole story. What's more, Alesis will soon be marketing (at very low cost) a rack adaptor that will allow you to mount two of these units side by side in 1U of standard 19 rack space.

Like the MIDIverb, the MIDIfex offers 63 preset delay and reverb effects which may be selected from the front panel or via MIDI on any one of 16 MIDI channels. No user-programmability is available, so you're stuck with the patches programmed by Alesis - though as this is a major factor behind the unit's low purchase price, there shouldn't be too many complaints.

The front-panel display normally reads the number of the preset selected, but when the MIDI Channel button is depressed, it shows the MIDI channel number that the MIDIfex is currently set to receive. In this mode, the MIDI channel may be changed using the Up/Down keys normally used for selecting presets.

In specification terms, twelve-bit quantisation is used (as on the MIDIverb) and the background noise is low enough not to have to worry about, provided you drive the input hard enough. Similarly, the bandwidth is limited to 10kHz (again the same as the MIDIverb), but this doesn't seem to cause too many problems with the type of effects being generated.

Both inputs and outputs are stereo and on phono connectors. There is no input level control, but there is a two-LED level meter, and the mix of direct and processed sound can be set using a Balance pot on the rear panel. A single Defeat button mutes the processed sound, and the same may be done by selecting a patch number above 63.

Where the MIDIfex differs from its forebear is in the nature of the treatments it offers, which, although being reverb-based, are quite a bit less conventional - and more complex - than those on the MIDIverb. In fact, quite a number of the new machine's effects couldn't otherwise be created without two outboard effects units. There are no chorus, flanging or vibrato effects, though, as it appears the hardware is unable to support them.

Presets 1 to 21 are called Echo, and have varying degrees of three parameters: Length, Filtering and Ambience. The presets are all delay effects that have no feedback, but some of them are more complex than they first appear.

The filtering is easy to understand: you get high-pass, low-pass, band-pass or no filtering at all. In other words, you get a sound with reduced bass, reduced treble, a middly sound or a natural sound. Delay too is fairly self-explanatory, maximum delay being about half a second.

"Effects: Having several taps spread across the stereo field with reverse reverb is a great aid to making a simple sound appear more complex than it really is."

It's in the Ambience column that the fun starts, because it's here that a simple delay can become anything but. There are three different Ambience settings, the first being Ambi, in which extra processing gives the delayed sound a sense of depth rather than just making it a blind copy of the input. On vocals this sounds warmer than a simple delay, and it also forms a useful treatment for instruments.

The second setting is described as Thick, which turns out to be particularly interesting. Again, the repeat is not a single straight copy of the input, but appears to be a burst of closely spaced reflections, rather like a gated reverb - this lends a 'bowing' effect to the echo. An obvious application of this is the treatment of synthesised strings, but it also sounds good on voice, electric guitar, and other synth settings, where the tightly-spaced reflections tend to disturb the rigidly coherent phase relationships that predominate simple synthesised sounds, giving a more natural character to the sound.

The third and final Ambience variation is Wide, which appears to be a double delay which has its two delays very closely spaced, one on each side of the stereo field. As its name implies, this gives the effect of a single delay or echo that has an enhanced sense of width. If a sound requires an echo treatment coupled with a stereo identity, it'll benefit from this setting.

The second row of treatments kicks off with 15 multi-tapped delays - nine two-tap and six three-tap. What this means is that each sound you input is repeated twice or three times. Again though, all is not as straightforward as it seems, as there are various panning tricks thrown in and the enhancements and filter settings used in the first row of treatments make another appearance.

What this adds up to is a variety of textural effects with a dramatic sense of stereo spread. Suitable candidates for treatment are electric guitar, piano, synth and possibly vocals, on which Short and Extra Short presets are useful in creating an ADT effect. Drums, though, tend to sound too messy when processed this way, unless you're after a specific messy treatment.

The rest of this section is taken up with regenerative delay effects, ie. treatments that have some feedback to give a repeating series of echoes. Again, filtering is employed and three of the presets use the above-mentioned ambience treatments to create the illusion of depth and width. These settings can usefully be employed in any situation where you might want a conventional repeat echo, and you do at least have the freedom to select the one that has the best filtering and ambience for your application. For example, a vocal track might benefit from the low-pass filtered version with ambience to give a warmer sound than you could obtain using a straightforward DDL.

The third section of effects starts out with a refreshingly uncomplicated set of four slapback effects, which on the face of it appear to be single, full-bandwidth delays with varying spacings. These are all short-delay treatments handy for beefing up handclaps or snare drums, and maybe for giving vocals a hard ADT sound.

Following on from here is a series of reverb and spatial enhancement programs. Gated reverb puts in an appearance, as does reverse reverb, and these are in addition to a medium warm reverb and a long reverb with high-pass filtering. These are all fine-sounding reverb treatments of the same calibre as their MIDIverb counterparts, ie. the sort of high-quality effects which, up until six months ago, you couldn't obtain unless you had over £1000 to spend.

"Background: Like the MIDIverb, MIDIfex has a list of patches on its top panel — though the names don't tell the whole story."

More unusual is a preset called Medium Bloom, which has a long build-up to the reverb, rather like the reverse setting, and then a gentle decay like a conventional reverb. Sounds great on vocals and wind instrument sounds.

There's also a reverb program with built-in panning, which is handy for adding movement and life to a static sound, and a setting called Reverse Regen, which is just like a conventional reverse reverb setting except that it repeats until it gradually dies away. Previously, the latter treatment was only possible with a reverse reverb patch plugged through a separate digital delay. It's an ethereal treatment, and it's sure to find a lot of different uses.

Following the reverb programs are three special multi-tap patches which combine elements from the multi-tap presets with reverb. The most involved is Multi-tapped Reverse Pan which, as its name implies, comprises several taps spread across the stereo field, accompanied by that characteristic reverse reverb effect. This gives a wonderful (and slightly unusual) moving texture, and is a great aid to making a simple sound source appear far more complex than it really is.

To finish, there are half-a-dozen spacial enhancement processes, two called Thickener and four called Stereogen. These all add ambience and colouration, and generate an impression of stereo spread without adding any perceptible delay - particularly effective on electric guitar and 'plucked' synth sounds. Because they add colouration, these effects can be used to disguise well-used preset synth or drum machine sounds, as well as to widen less common sounds from acoustic or electronic instruments. They could even form the basis of some interesting treatments for backing vocals.

ALL in all, the MIDIfex is a difficult machine to evaluate. No other single device currently on offer represents competition for it, and there are treatments available within it that no other signal processor - regardless of cost - can achieve.

That said, a first encounter with the MIDIfex isn't necessarily as impressive as the equivalent meeting with a MIDIverb. Skim briefly through its presets with a drum machine or an electric guitar, and you could easily dismiss many of them as unsuitable. Check out all the treatments with an electric piano, and you could come to the opposite conclusion. That's how distinctive the new Alesis' treatments sound.

The bottom line, though, is that the MIDIfex gives inexperienced (and relatively penniless) musicians and engineers access to complex production effects that might otherwise need a lot of expensive outboard gear and expertise to emulate. And the fact that these effects sound completely different depending on what you feed through them means there's less chance of them becoming cliched.

At a time when so many musicians and producers are using the same effects, the same samples, and the same preset synth voices, it's nice to be confronted with a machine that gives you the chance to be individual. How ironic, then, that it should also be a machine that offers no programmability at all.

Price £395 including VAT

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