Cross Wave Synthesiser
The successor to Ensoniq's popular ESQ1 expands on the sound and sequencing facilities and adds polyphonic aftertouch to the ESQ's spec. Simon Trask goes in search of the performance synthesiser.
Ensoniq's latest synth is an upmarket version of their popular ESQ1. Does it have enough new features to establish itself as a "new" synth or will it become the ESQII?
IN THE FIELD of sound synthesis it is no longer the Americans but the Japanese who make the running. Many once-great American companies are no more, and Yamaha's take-over of Sequential is only the latest nail in the coffin of the Great American Synth Manufacturer. Now only Ensoniq are carrying the US flag - interestingly they are carrying it into Japan, where they've become the first American manufacturer to set up a distribution operation in the land of the rising sun.
The company's latest synth is an enhanced version of their well-established ESQ1, complete with onboard eight-track sequencer. Costing around £300 more, the SQ80 is set to compete with Roland's D50 and Yamaha's DX7II.
MAJOR IMPROVEMENTS OVER the ESQ1 are 43 extra waveforms, pseudo-reverb, polyphonic aftertouch, generic SysEx storage, an onboard 3.5" disk drive, and twice the number of sequences and songs. There are also small but useful additions like MIDI Thru and a headphone output.
ESQ1 owners will have no trouble getting to grips with the SQ80, as the panel layout is virtually the same; Ensoniq have retained the generous 80-character fluorescent display of the ESQ1, with its "soft" buttons for selecting up to 10 parameters or patches.
Also like the ESQ, the SQ80 stores 40 patches internally and a further 80 on cartridge, giving instant access to 120 sounds. The internal patches are organised in four groups of 10, with one group at a time being called into the display.
The SQ80's 3.5" disk drive can store 40 patch banks (sets of 40 patches), 128 individual patches and 10 sequencer/SysEx blocks on one double-sided double-density disk. That's 1728 sounds per disk, which seems pretty economical compared to the 80-sound capacity of the SQ's cartridge. Loading a bank of 40 sounds from disk takes a mere five seconds.
To build a keyboard with polyphonic aftertouch as economically as possible, Ensoniq have designed their own system. The result (which is also fitted to Ensoniq's new EPS sampler) has a distinctly odd touch, clunky and with a shallow action which offers no feeling of substance. After an uneasy beginning I got used to it, but I wouldn't call it one of the instrument's strong points.
On the plus side, there's a choice of 16 velocity/aftertouch response scales ranging from soft to hard. You can also select channel or polyphonic aftertouch, which is useful when playing a MIDI instrument that doesn't have polyphonic aftertouch capability (most instruments). It's also useful as a means of economising on sequencer memory, as poly aftertouch eats up the bytes.
The SQ80 offers no increase in polyphony; eight voices is the order of the day. But, as on the ESQ1, dynamic voice assignment helps to make this number seem greater in practice - it's particularly useful when you're recording with the onboard sequencer or using the SQ80 as a multitimbral expander.
A further advantage of the SQ80's voice allocation is that selecting a new patch doesn't cut short any notes that are currently playing (as happens on many synths). In fact any notes held when you select a new sound will "overlap" into that sound, a feature which can be put to good practical use.
You can also select Split, Layer and Split/Layer keyboard modes. The latter allows you to split and layer at the same time and, like Layer, reduces the onboard polyphony to four voices.
THE SQ80 STORES 75 different "waves" in 256 Kilobytes of ROM. The first 32 of these are the same as those found on the ESQ1, providing classic synth waveforms such as sawtooth and square waves, together with sampled waveforms such as bass, piano (multi-sampled) and voices, and other waveforms derived from additive synthesis and a process called "time-domain formant wave-function analysis" (I don't know what it means, either).
A further selection of sustain waveforms (a mixture of sampled, synthesised and resynthesised) includes three Grits and two Glints. The Grit waveforms are raw noise sounds "not recommended for polite company", while the Glints are high harmonics useful for adding a glassy shimmer to a sound. Other sustain sounds are the Inharmonic Loops, composed of sampled segments of sound longer than a single wavecycle: breath, voice, steam, metal and chime.
Eleven Transient Attack waves most closely resemble the D50 in concept - being the initial attack transients of a number of instruments - yet some are created using additive synthesis and resynthesis. Here you get bowed cello (multi-sampled), electric and steel-string acoustic guitars (multi-sampled), vibraphone, slap bass, several "plinks" (one of which started life as two wine glasses being struck together), flute chiff, piano hammer "thump" and a click (ideal for Hammond organ impressions).
Finally, Ensoniq have provided five individual drum samples and five multi-sampled drum kits offering various combinations of those sounds. More specifically: log drum, bass drum, snare, tom-tom and hi-hat. Not exactly a comprehensive kit, but the real value of these sounds is that they can be used to create a basic rhythm track within the SQ80 - though of course at the expense of internal voices for other tracks.
Essentially there are two types of basic sound material on the SQ80: attack and sustain waveforms. The term Cross Wave Synthesis refers to the SQ's ability to mix or crossfade these waveforms. Although there are some similarities to the D50, in practice the quality and range of the SQ80's sounds are quite different from those of Roland's flagship.
"Selecting a new patch doesn't cut short notes that are currently playing - notes held when you select a new sound will 'overlap' into that sound."
The SQ80's basic voice architecture is straightforward enough: three DCOs per voice, each with their own DCA, are fed through a single analogue four-pole low-pass filter to a master DCA and finally through a panner. In addition, oscillators one and two can be hard synced, and oscillator one can be set to amplitude modulate oscillator two.
The SQ80 also has 15 modulation sources: three LFOs, four envelopes, velocity (linear or exponential), aftertouch, keyboard tracking (two types), mod wheel, footpedal and external controller. Each of the DCOs and DCAs can be assigned two modulators, as can the filter; DCA4 and the panner get one apiece. This sort of modulation flexibility is akin to that found on Oberheim's Xpander and Matrix synths.
The possibilities are many, but for instance, you could set velocity to modulate DCA1 and the filter cutoff frequency, and aftertouch to modulate DCO2, so that a harder keystrike brings in the DCO1 wave and at the same time brightens the overall sound, while changes in key pressure alter the pitch of DCO2. Each modulation has an associated depth parameter (+/-63), allowing you to control the degree of the effect. For instance, the DCO1 wave may make a dramatic entrance or it may subtly underpin the other waves, while the DCO3 wave may fluctuate slightly in pitch or it may leap up an octave.
The filter has been given frequency and resonance settings. You can also set a keyboard tracking parameter which determines how (or if) the filter cutoff will follow the keyboard, while two modulators may be assigned to control the filter cutoff frequency dynamically. You could, for instance, choose velocity and aftertouch as modulators, resulting in dynamic control of brightness. It's a shame that, while adding so many other features to the SQ80, Ensoniq didn't provide a filter for each DCO/DCA pair.
After filtering, the sound signal is passed through DCA4, which is the master volume envelope control which Ensoniq have "hard-wired" to this DCA - a sensible move.
The final sound stage is the panner, which allows the sound to be placed at one of 15 positions in the stereo field. This is particularly valuable when you're using the SQ80 multitimbrally, as you can introduce a spatial organisation to the sounds emanating from the synth's stereo outputs. It's also possible to create dynamic spatial effects by using any one of the 15 modulation sources.
Each LFO offers four waveforms: triangle, sawtooth, square and noise. Additionally you can set frequency, initial level, delay, output level modulation source (for some interesting modulation "chain" possibilities), reset, and human feel. When manufacturers talk of "human feel" they usually mean random operation (how many random people do you know?); Ensoniq are no exception.
The envelopes each offer three levels and four times. Unusually, changes in level take place in absolute time, this means that the same time applies whether a change in level is small or great. There are 63 different time values available, of which the longest is 20.48 seconds.
For added flexibility there's a velocity attack control (higher velocity values decrease the attack time) and keyboard decay scaling (times two and three are decreased as you move up the keyboard). Additionally there's the pseudo-reverb feature mentioned earlier, which is actually a second envelope release stage: instead of fading to zero volume during time four, the envelope drops to a low level, after which it fades to zero at a fixed rate. With careful setting of levels this can be quite effective, though still no substitute for digital reverb. On the other hand you can give each sound its own "reverb" setting in multitimbral mode.
THE ONBOARD SEQUENCER is an integral part of the SQ80, offering eight polyphonic tracks each of which can store data on a single MIDI channel. Ensoniq have doubled the ESQ's number of sequences and songs to 60 and 20 respectively, though the amount of memory (64K or 20,000 notes) is the same as an ESQ1 with maximum memory expansion. I found the SQ's sequencer remarkably easy and quick to use.
Each track within a sequence can be assigned its own MIDI channel, patch number and volume level. Additionally you can set track status to local, MIDI, both or sequence - essentially defining what combination of internal and MIDI voices the track will play on. Along with the eight tracks there is also the "straight synth", which is the patch allocated to the SQ's keyboard when no track is selected; this has its own MIDI channel.
Sequence length can be predefined or else defined by the length of the first track recorded, though you can shorten or lengthen a sequence at any time (from the end only). Additionally you can append and copy sequences.
Punching in and out of a track is done manually using the sequencer footswitch. Whenever you change a track, the SQ80 gives you the opportunity to audition both versions before deciding which one to keep. There are five track edit functions: Transpose (+/- up to one octave), Remove Controllers (non-selectively), Quantise (up to 32nd-note triplets), Erase and Merge. Merging two tracks puts them both on the MIDI channel of the destination track, as the SQ80 only allows a single channel per track. Tracks can be muted and demuted manually at any point, but these actions can't be stored. The SQ80 also provides step editing, with the ability to punch in/out on a single clock beat if required.
"The SQSO's Transient Attack waves most closely resemble D50 in concept... yet some are created using additive synthesis and resynthesis."
Songs can be up to 99 steps each, with a maximum 99 repetitions specifiable for each step. The tempo and time-signature assignments given to each sequence are retained in Song mode, and sequences can be transposed for each step.
Well-specified the SQ80's sequencer may be, but it's certainly not the be-all-and-end-all of sequencers. I hope that any ROM software update for the SQ will see it adopt the new MIDI Files standard, as the ability to transfer sequences to and from a computer-based sequencer can only be a good thing. At present, you have to play tracks over one at a time.
Of course the SQ80 can equally well be a slave sound source for an external sequencer or other MIDI instrument, providing access to up to nine sounds at a any given moment (eight tracks plus the "straight synth"). The synth's dynamic voice allocation can make its eight voices seem like a good deal more. Additionally, each track responds independently to controller and patch information.
Ensoniq have also designed the SQ80 to be suitable for MIDI guitarists, with mono mode and global controller channel implemented. However, anyone wanting to use the SQ's sequencer will either have to switch their guitar to poly mode or record one string at a time.
The SQ's sequences can come in useful even if you haven't recorded anything in them. Each time you call up a sequence its associated internal and MIDI assignments for each track will also be selected. In this way you can call up patch changes and volume levels for up to eight MIDI channels, together with associated track status assignments which allow you to decide the combination of internal and external sounds that you want to use. By selecting different Sequences and different tracks within each Sequence you can quickly call up a completely new texture. If you chain "silent" Sequences together into Songs (remember that the SQ80 can store 20 Songs of up to 99 steps each) you can automate your texture changes. Yet another option would be to dedicate some tracks to changing patches on any MIDI'd signal processors you may be using.
THE SQ80 CAN also be used as a generic SysEx storage device, in which case its 64K sequencer memory becomes a transmit/receive buffer for SysEx data. This setup only works for instruments which don't require any handshaking to initiate transfer, which rules out such popular instruments as Casio's cheaper CZs and Roland's MT32.
As you can only store 10 sequencer or SysEx files on a disk, no matter how much or how little data there is in each file, it makes sense to cram as much data as you can into a single file. The SQ80 automatically queues SysEx files in its sequencer memory, so it's an easy matter to accumulate several files and then save them as one file to disk.
PATCHES AND SEQUENCES can be transferred over MIDI individually or as a bulk dump to another SQ80. Ensoniq have also ensured MIDI-transfer compatibility between SQ80 and ESQ1 in either direction. However, if an SQ80 patch uses waves not found on the ESQ then you're going to get unpredictable results, while some adjustments may be needed on the ESQ1 to sounds which use the new synth's pseudo-reverb feature. Sequences can only be transmitted individually from SQ80 to ESQ, due to the former's greater number of sequence locations, but ESQ owners who have availed themselves of a Mirage for disk storage of ESQ sequence data will be pleased to know that this data can be transferred to the SQ80.
Compatibility is the name of the game, which is presumably why Ensoniq have given the SQ80 a tape storage option - ESQ owners with a library of sounds and sequences on tape can load them into the SQ80.
Finally I must mention the SQ's manual, which is so good that it wins my Manual of the Year award, despite missing out on an index and a troubleshooting section. Required reading for all manual writers.
"THE FIRST STUDIO synthesiser designed for live performance", is how Ensoniq see the SQ80, and it's easy to see how it will go down well in both environments with its wealth of well thought-out features.
There are enough extra features on the SQ to make it an attractive alternative to the ESQ1 for those musicians who have the extra money. And while its vocabulary of sounds is greater than that of the ESQ1 (courtesy of those extra waveforms), ultimately it has the same sonic character as the earlier synth. If you like the ESQ1 then you won't be disappointed by the SQ80, which offers more of the same; conversely, if you prefer the sounds of a D50 or a DX7II then the SQ80 is unlikely to tempt you.
While the Japanese concentrate on developing synths which aim to sound as natural as possible, the SQ80 is a synth in the grand American tradition. It doesn't have the clarity and sparkle of Roland's D50, nor that instrument's sense of realism. What it does have is a grittiness and warmth, and a "synth-like" quality in the tradition of Oberheim and Sequential, that make it distinct from the DX7s and D50s of this world. I'd say that's no bad thing.
Prices SQ80 £1395; STC8 RAM cartridge £64; CVP Foot Pedal £27.60; ESQ1 Voice Cartridges £46.30; all prices include VAT
More from Ensoniq UK, (Contact Details)
Review by Simon Trask
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