Emu Classic Keys

Emu's Vintage Keys module offered a tempting selection of sounds sampled from the cream of desirable analogue synths. Now the same concept has been remodelled, with a lower price tag to appeal to a larger range of musicians. Gordon Reid assesses the Classic Keys.

Is another S+S rackmount module what the world really needs in 1994? Just about every manufacturer seems to think that it's the only method of sound generation worth using, so almost every new synth or module offers yet another variation on the common theme.

Consequently, a number of companies have attempted to find 'USPs' (Unique Selling Points) to help separate you from your dosh. One of the best of these was a spiffing wheeze announced by Emu two years ago. Vintage Keys was a brilliant idea: just pop some waveforms from a bunch of analogue synthesizers into the ROM of an existing S+S synth (such as a Proteus) and tell the reviewers that it sounds almost identical to the £50,000‑worth of instruments it claims to emulate. Emu were so successful in this that they even got people to forget that Vintage Keys' sound generation system and filters were pure digital. Or, to put it another way, they took an all‑digital S+S synthesizer and, by deriving a new set of PCMs from tiny snippets of synthesizer waveforms, convinced the world that it sounded like Moogs, Oberheims and ARPs.

Therefore, since Classic Keys is a direct derivative of the original (digital) Vintage Keys, lacking the (digital) filters of its progenitor, and substituting a (digital) effects section in compensation, you could immediately dismiss it as a (digital+digital+digital) con and turn to the free‑ads to track down that elusive yet affordable mint condition CS80 you've been seeking for the last few years. Is it that simple? Maybe not...

Overview

Physically, Classic Keys is slim, black, 1U high, and well built. It features the dreaded parameter/value programming system, but it's a pleasant surprise to find that, thanks to the clear and simple front panel, it's a doddle to program and use.

CK is based on 8Mb of samples drawn from the Emulator III sound library, and uses these in place of the 'oscillators' of a conventional synth. Unfortunately, there are no filters, resonant or otherwise, to modify the sounds so, whilst you can apply envelopes, LFOs and effects, you cannot alter the samples' fundamental tones. This means that, despite the module's name, you can't duplicate any fashionable analogue filter‑sweeps and bleeps unless there is a sampled waveform which already features the effect. Nevertheless, with hundreds of samples to choose from, 512 patch memories, and a whole bunch of effects to pass them through, there are bound to be enough hidden goodies to make life interesting.

Samples

Classic Keys incorporates 249 samples. Some are derived from genuine keyboards, others from orchestral instruments and percussion, some are digitally generated, and there are a handful of loops and 'piles' — continuous loops containing multiple samples. Emu state that the samples are presented to the 18‑bit digital‑to‑analogue converter at 39kHz, and 8Mb therefore represents 205 seconds of sound. However, this doesn't mean that each sample has nearly a second allocated to it: many of the sounds are multi‑sampled so that they can be played back without 'munchkinisation'. Consequently, whilst one or two of the Instruments (Emu‑speak for extended samples) occupy several seconds of ROM, others are truly microscopic. Surprisingly few are genuine samples of true classic keyboards: in a concession to the 'one box for everything' mentality, Emu have also included waveforms from saxophones, trumpets and trombones; 12‑string, electric and bass guitars; and 16 percussion instruments arranged as a standard drum kit.

Inspecting the samples couldn't be simpler because Instrument 249, 'Memory loop', allows you to dump the entire memory to your own sampler. I couldn't resist having a peek at the raw data, and using a Roland S770 I was quickly able to determine which samples were genuine, and which were digital constructs.

I had a close look at a number of the true samples, discovering, for example, that the Moog square‑waves (of which there are six) bear virtually no resemblance to true square‑waves. This is exactly as it should be — the output of the oscillators on early synths may have been square‑ish (or sawtooth‑ish or whatever) but once passed through resonant filters, envelope generators, amplifiers, and yards of low‑quality wiring, they bore very little resemblance to their initial shapes. This, of course, is where the characters of early synthesizers came from. After all, if they had all produced true waveforms and modified them with mathematical precision, they would all have sounded the same. Nevertheless, if you want to build new sounds using pure waveforms, samples 101, 102 and 103 offer digitally generated square, sawtooth and triangle waves. Very useful they are too.

It would be impossible, even with 8Mb available, to do more than scratch the surface of the range of classic keyboard sounds that have flourished over the past 30 years. Consequently, many favourite samples are missing from Classic Keys. Perhaps the most culpable omission is that of the DX7 electric piano. I would also have liked to see more Mellotron tapes included, alongside the RMI Electra‑piano and organ modes, Roland VP330 Strings and Human Voice... Thinking about it, Classic Keys should have a PCM card slot, and Emu should make more of the EIII library available this way. It would significantly increase the attraction of this module.

Patches

Classic Keys features 512 patches held in four banks of 128 each. Of these, 256 are in ROM and are therefore unalterable, and 256 are in RAM, so you may edit or replace these as desired. Two samples can be used in each patch, one placed in each of a 'primary' and a 'secondary' instrument location; these can be split or layered over part of, or the entire length of, the keyboard. There is no restriction on which samples you can use in each patch, including using the same one twice.

Although Classic Keys lacks filters, the patch editing parameters are extensive. For example, instruments can be tuned, panned, chorused, delayed up to 14 seconds, started up to 100 samples within the sample, and reversed (although this defeats any looping). In addition, whilst there is a preset amplitude envelope for each sample, this can be defeated and a 5‑stage AHDSR (= hold time) can be programmed independently for each of the primary and secondary instruments.

There are two well‑endowed LFOs — each having not only the standard rate and depth controls, but also 'var' (variation) which randomly varies the LFO rate each time a new note is pressed. The LFOs have five waveforms; triangle, sine, sawtooth, square, and 'random', which can be routed to pitch, thus simulating analogue oscillator instability. This is vital for programming convincing Mellotron imitations.

CK also offers a 5‑stage auxiliary envelope which can be routed to any one of 24 (!) different modulation destinations, as can, simultaneously, the pitch wheel, four MIDI controllers, channel pressure, poly‑pressure, and both LFOs. Not enough? OK, how about 33 modulation destinations for key velocity and note number, three of which are low‑pass filters. Hold on a minute... filters?

Would you believe it... there are three simple low‑pass filters in CK! You can't access them directly, but you can via the keyboard, either brightening the sound as you play harder and/or as you move up or down in pitch along the keyboard. This, of course, is velocity sensitivity and keyboard filter scaling. Almost totally overlooked in the factory presets, these filters are hidden so deep that it took a week to find them. But once discovered — lo and behold — expressive pianos, responsive key‑scaled pads and dynamic lead‑synth patches... CK came alive, with vastly‑improved previously disappointing patches such as the Clavinet (which, as factory programmed, has minimal velocity response and no tone response).

Now, moving on... have I mentioned the cross‑fading? Velocity curves? Solo Mode? Just, Vallotti, 19‑tone, Gamelan or user‑defined tuning? Linking of up to eight instruments in window‑shattering overlays or 8‑part keyboard splits? Well, tough. There's no more space.

The Effects

One of the major differences between Classic Keys and Vintage Keys is the substitution of CK's effects section in place of VK's digital filters. A 'bussing' system allows you to route any proportion of a patch's output to the main output buss (i.e. untreated), or to either of Effect section 'A', Effect section 'B', or to 'B' followed by 'A'. There are 24 'A' effects: 11 reverbs, four early reflections, reverse early reflection, stereo chorus, stereo flanger, stereo phaser, echo, delay, cross delay, and two spatial reverb/delays called 'Rain' and 'Shimmer'. 'B' offers eight somewhat different effects: stereo chorus, stereo flanger, phaser, delay, cross delay, fuzz, fuzz lite, and ring modulation. However, you pay for the range of effects by having limited control over each of them. For example, the reverbs have only one parameter (decay time), so you can only control warmth or diffusion by choosing the most suitable (or least unsuitable) of the 11 algorithms.

The algorithms themselves are very quiet and lack the granularity of some of the cheaper effects units. I particularly liked the stereo chorus and flanger, which were smooth, subtle, and musical. I suspect that even Space Echo or Echoplex fans could be kept happy by routing the signal B‑>A and combining these with one of the multi‑tap delays.

Unfortunately, there is a drawback: CK's effect section is 'global' — you can only apply it to the instrument as a whole. Like having two external effects boxes, this means that the same effects are always applied unless you call the 'global edit' menu and manually change the algorithms, parameters and mixes every time you select a new patch. In the studio you can dump and recall effects via MIDI, but as for live work... imagine the hassle caused when two patches used in the same song require totally different effects. I suspect that some players will simply end up bypassing the internal effects altogether.

Having said all of that, I can forgive a lot if a synthesizer features a ring modulator. Whilst digital RMs lack the depth and warmth of their analogue forebears, the implementation in CK is very user‑friendly, easily re‑creating the clangorous tones of wall‑sized modular synths. I love it.

MIDI

Classic Keys supports four MIDI modes: Omni, Poly, Multi, and Mono (which is also multitimbral, but only permits one note at a time on each of the 16 MIDI channels). Unfortunately, it has no 'Performance' memories unlike, say, an M1 which has 100, or a U220 which holds 128.

In addition to the 31 routing possibilities for standard MIDI controllers, you can simultaneously assign three foot‑pedals to MIDI controller destinations. There is also a programmable 'map' which overcomes MIDI's inability to understand more than 128 patches, and allows any incoming MIDI program number to recall any of the 512 patches. And, as for SysEx... CK has a full complement of dumping capabilities: all patches, selected patches, factory patches, effects settings, master settings, the program map, and the tuning table.

Finally, if you're into MIDI programming, you can access every CK parameter via SysEx, and the manual has a complete explanation of the command protocols, specifications, and parameter maps.

Conclusions

In recent months, an SOS series explained how to imitate analogue synths using the editing and filtering facilities of the JV880, which has a similar price to the Classic Keys. And there's Roland's Vintage Analogue expansion board itself, which fits all the JV and JD synths and features many of the sounds of Classic Keys. So why buy the Emu module?

The answer is, as always, one of taste. Many players will like the sound of Classic Keys, and will be more than satisfied with its deceptively simple‑looking editing capabilities. OK, so it has some deficiencies, the worst of which are (i) the unsuitability of the effects section for live work, (ii) the lack of any card slot or other expansion capability, and (iii) the stereo (as opposed to multiple) outputs, which never seem adequate for multitimbral use. But these are, at least in part, balanced by bonuses such as the ring modulator (which most of the Rolands lack).

I must admit to never having been a fan of the Proteus modules from which both Vintage Keys and Classic Keys are derived. I found them rather dull and lifeless compared to, say, Korg's Wavestations or Roland's JV series. But Classic Keys, which produces little or no residual hiss, displays no coarseness or granularity as samples and reverbs decay into silence, and which has both clarity and depth (if not tweeter‑challenging brightness), is capable of producing the goodies it promises.