U Got The Look
Roland U20 Keyboard
Is the U20 just a revamped U110 with a keyboard or does it have what it takes to de-throne the Korg M1? Paul Ireson finds out.
Is the U20 just a revamped U110 with a keyboard or does it have what it takes to de-throne the Korg M1? Paul Ireson finds out.
The U20 is a multitimbral keyboard whose sounds are provided by a replay-only sampler section very similar to the U110. From this unit the U20 has inherited the concept of providing complete, pre-sampled instruments with the minimum of sound editing facilities, and also many of its sounds and operational features. However, it improves on the U110's sound facilities in many important respects, essentially dealing with all of the criticisms that were levelled at that unit, and more besides. To control its sounds, the U20 has a five-octave velocity and aftertouch sensitive keyboard, two assignable control sliders, and control and performance facilities that make the U20 more than just a U110 with a keyboard: enough to make it a good master keyboard, in fact.
The features of the U20 are best viewed as falling into two categories - sounds and control - not least because this natural division presents itself in programming, playing and using the U20. The two most often used play modes - Keyboard play and Sound play - are selected with buttons at the top left of the front panel. In Sound play mode, the Bank and Number buttons on the right of the front panel select Sound Patches. In Keyboard play mode the same buttons select Keyboard Patches. Sound Patches determine exactly what sounds are used in the U20's internal sound module, and the Keyboard Patches define how the keyboard, pitch bender and controller sliders are used to control and play these sounds or external MIDI devices. The U20 is therefore best viewed as a controller keyboard and a MIDI sound module combined into the same unit. Setup parameters determine some basic features of how the Keyboard and Sound sections communicate, such as whether MIDI Local is on or off.
The U20's sounds are the best place to start an in-depth look at the instrument. As on the U110, the basis for the sounds is a selection of samples, which can only be slightly modified on playback - the point of this is that many users want good preset sounds without having to work to create them. The U20's sounds therefore include all of the most commonly demanded 'off the shelf' instruments: pianos, acoustic guitars, brass, strings, synth basses, choirs, vibes, drums etc.
The U20's sounds are organised at the highest level by the user-programmable Sound Patches already mentioned: 64 of these can be stored in the internal memory. Each Sound Patch consists of six Parts plus a seventh dedicated Rhythm Part, all of which can be processed by the on-board digital effects section. This structure allows the creation of layered sounds, splits and velocity switched sounds, or multitimbral setups for use with an external sequencer. Each of the six Parts plays one of 128 user Timbres. These Timbres are based on the 128 preset Tones that the U20 contains: the Tones cannot be altered in any way, so the Timbres provide a means of varying the basic sounds that the instrument offers. Referring back to the U110, the Timbres are a new level of organisation in the sound structure. On the previous unit, the Tones were addressed directly by the parts of Sound Patches, and any edit 'tweaks' to the Tones were made at this point: the U20's arrangement makes it much easier to use the same customised version of a Tone in several Patches.
The Tones themselves are pre-sampled, looped sounds, in many cases multi-sampled and even velocity switched as well: complete sampled instruments in fact. Roland have therefore cut out all the hard graft involved in creating playable instrument sounds from raw samples. Five types of Tones are present in the machine: Single, Velocity Switched, Dual, Detune and Velocity Mixed. Single and Velocity Switched Tones use only one of the U20's 30 voices per note, and the other types use two, as they replay two samples to create a more complex sound. Dual Tones combine two different samples, Detune Tones double up the same sample to produce a thicker sound, and Velocity Mix Tones introduce the second Tone only when you strike the keys harder.
Most of the U20 Tones are the same as those found on the U110, although several have been lost in the transfer, and still more added to take the total number up to 128 (as opposed to the U110's 99). The extra Tones consist almost entirely of synthesizer sounds - a good choice, which extends the U20's range of sound well beyond that of the U110, which remained mostly in 'acoustic' territory. I refer you to the separate panel for a complete list of the Tones.
My major complaint about the U110 was its disappointing sound quality. I'm happy to report that the U20 has fixed the problem entirely, to an extent where it's not really fair to mention the two instruments in the same breath (unless you happen to be saying how much better the U20 sounds). Whereas the U110's sounds were rather noisy and in some cases affected by a grainy distortion, the U20's Tones sound beautifully clean and clear. The difference in sound quality is quite astonishing: a side-by-side listening test, in which both sets of Tones were played totally dry, only reinforced my initial impression of just how good the U20 sounds. The difference is most noticeable on the decay portion of quiet sounds.
This, presumably, has more than a little to do with Roland's employment of 'RS-PCM' technology on the U20, as opposed to standard PCM on the U110. 'RS' stands for re-synthesis, and this is the first time that Roland have used this particular variant of PCM playback in their instruments (the W30 uses another technique called DC-PCM). There is no indication in the manual of just what RS-PCM really is, but frankly I don't give a damn: it sounds marvellous and that's what counts. RS-PCM is at least sufficiently similar to PCM that the U20 can use the same PCM library cards that are currently available for the U110. These enable you to add extra Tones to those in the internal memory.
As they stand, the Tones may not be quite right for the context in which you want to use them, so the U20's Timbre parameters allow you to make some basic modifications to the sound. Each Timbre can use any Tone as its sound source, and you can give it a name to remind you of what kind of sound it is: 'Short Strings' for a string sound with a very fast release, or whatever. Other Timbre parameters fall into three categories: those relating to Level, Pitch and Vibrato.
Level parameters allow you to set a basic volume level for the Tone, velocity sensitivity, channel aftertouch sensitivity (ie. how much the volume rises with key pressure), and envelope attack, decay, sustain and release. These envelope parameters are not absolute, as on a synth, but rather relative to the basic envelope characteristics of the source Tone.
Pitch parameters allow you to apply coarse and fine tuning modifications to the Tone, specify the range of bend up and down that the bender/modulation lever produces, specify how many semitones up or down each note will be bent by polyphonic and/or channel aftertouch, and create an auto-bend effect whereby the U20 bends up or down to each note over a specified range and at a specified rate. A Detune Depth for the Detune Tones can also be specified as a Pitch parameter.
Vibrato parameters allow you to specify the rate, depth, delay, waveform, rise time, and polyphonic and channel aftertouch sensitivity of the effect. I was pleased to find the same polyphonic aftertouch response as on the U110, in respect of vibrato control especially, but it is a shame that Roland didn't go a little further and allow polyphonic control over note volume as well - however, many units don't allow polyphonic aftertouch control over anything, so this is a minor point.
Four Rhythm Sets can be created on the U20, which are essentially the drum equivalent of Timbres: the six Parts play Timbres and the Rhythm Part plays a Rhythm Set. Each note of a Rhythm Set has a source Tone and key, so each note of the Set can be any note of any U20 sound. The obvious thing to do here is simply to assign each of the drum Tone samples to a different note in the Set, but you could add anything else you wanted to as rhythm sounds: bass guitar notes, marimbas etc. For each note, Level parameters (level, velocity sensitivity, envelope mode, attack, decay and release) and Pitch parameters (coarse and fine shift, channel and polyphonic aftertouch sensitivity, pitch randomise, auto-bend depth and rate, and detune depth) allow you to introduce a welcome degree of variation and real-time expression into the drum sounds. I found the pitch randomise facility very useful when used carefully, to spice up hi-hat and snare parts in particular. Each note of a Rhythm Set can be made to mute any other when it plays (ie. new note priority) - an essential feature for allowing accurate simulation of conga or hi-hat parts, where in real life only one of the several variations of a sound could be played at any one time.
Timbres are used within Sound Patches by assigning them to one of the six Parts of a Patch; Part parameters then determine how this Timbre responds to MIDI data and how its audio signal is processed. The Output parameters specify which of four stereo busses the sound of each Part is routed to, and a pan position within this buss. An interesting option is the facility to randomise the pan position, whereby each note generated by a Part's Timbre appears at a random position in the stereo picture - very effective on electric piano.
The four selectable busses are Dry, Direct, Chorus and Reverb. The Chorus and Reverb busses feed different points in the U20's effects section, the Dry bus appears at the left and right stereo Mix outputs where it is combined with the output of the effects section, and the Direct bus feeds a second set of stereo output jacks on the rear panel - labelled 'Direct'. The front panel volume slider affects only the output from the Mix jacks - the Direct signal is always output unattenuated.
Dry, Direct, Chorus and Reverb output routing can be specified for each note of a Rhythm Set. I found the provision of Mix and Direct outputs to be a good compromise between a single set of stereo outputs and multiple polyphonic audio outputs, both in terms of convenience and flexibility of sound isolation. The compromise presumably extends to price as well: four extra jack sockets can add considerably to the price of a keyboard.
On the subject of outputs, another aspect of the U20's operation that is significantly improved over that of the U110 is the voice allocation between Parts. Whereas the U110 required you to select one of around 30 output modes, each with a different allocation of voices between six output groups, the U20 (thankfully) offers dynamic voice allocation, with the facility to reserve voices for particularly important parts so that note stealing becomes less of a problem.
Each Part can be set to receive on any MIDI channel, and made to respond only to a specified range of notes or velocity values - thus, two Parts can be programmed to respond to data on the same channel, but with one responding only to velocity values below 100, and the other only to values of 101 and above: the result is a velocity switched sound.
A U20 Sound Patch also contains parameters that control the Rhythm Part and effects section, so a different rhythm section and processing arrangement can be called up for each Sound Patch. Just as a Timbre is selected for each Part, so a Rhythm Set is selected for the Rhythm Part, with its own level and receive channel. The effects section of the U20 offers both reverb and chorus. The two effects are independent, in that there is no trade off in the complexity of effects between them (ie. any of the chorus section algorithms can be used with any of the reverb section algorithms), and the effects can be used in series or in parallel. The reverb section offers: three room programs, two halls, one gate program, and two delays (mono and stereo). The chorus section offers several choral variations and flanger effects.
The chorus section's audio output can be routed either to the reverb inputs or direct to the Mix outputs where it is combined with the reverb output and any Dry signals. This choice, together with the ability to send each Part to the Chorus, Reverb or Dry busses, makes the on-board signal processing side of the U20 very useful: rich treatments can be created, and different Parts given entirely different effects processing if desired. The sound quality of the effects section is very high, as it must be to do justice to the quality of the U20's unprocessed sound.
So far we've only looked at the sound side of the U20: equally important is the keyboard and control side of the instrument. The U20 has a five-octave velocity and channel aftertouch sensitive keyboard, with further sources of MIDI controller data being provided in the form of a pitch bender/modulation lever, two programmable sliders located next to the volume slider, and an optional expression foot pedal. These last three can all be programmed to generate any MIDI Continuous Controller data in real-time, and used to modulate some of the U20's sound parameters, or parameters of external MIDI effects units, etc. The 64 user-programmable Keyboard Patches each store a single configuration that determines what data is generated by these various controllers, so you can create Keyboard Patches that are suitable for playing Sound patches, or external modules, or both.
Each Keyboard Patch has a basic transmit channel. This can be specified as 1-16 or 'Set'. If the channel is 'Set', then the U20 refers to a Setup parameter to determine what channel to transmit on. This enables the transmit channel of several Keyboard Patches to be altered by changing only the Setup transmit channel parameter. Each of the two sliders and the expression pedal can transmit controller data on either the Keyboard transmit channe, or on a second dedicated control channel. This control channel can also be used to send out a Program Change message when the Keyboard Patch is selected: you can specify any MIDI channel and any Program Change number for each Patch.
Up to three of the U20's sound parameters can be assigned to be modulated by continuous controllers. The Timbre parameters that can be assigned include level, envelope parameters, detune depth, and all vibrato parameters apart from aftertouch sensitivity. The effects parameters that can be assigned include chorus level, chorus rate and feedback, reverb level and delay feedback. If any effects parameters are to be modulated, the controller data must be received on a Control Receive channel, which is specified as a Setup parameter common to all Patches. If Timbre parameters are to be modulated, then the appropriate controller number will modulate the assigned parameter of whatever Part is set to receive on its transmit channel.
A particularly unexpected aspect of the U20's control facilities appears in the form of performance buttons marked Transpose, Chord 1, Chord 2 and Arpeggio - not usually found outside home keyboards, though this harks back to the days of analogue synths like the Juno 60 and Jupiter 8. I was initially put off by the presence of these controls, probably more because of hi-tech snobbery than a reasoned objection to their use, and in fact they turn out to be rather well implemented. For each Keyboard Patch, each of the two Chord buttons can be programmed to access one of eight user-programmable chord sets. Each of these sets consists of any chords of up to eight notes, assigned to each note of an octave - each note's chord can then be generated from a single key in Chord play mode. The facility to assign any 12 chords to the notes of an octave does make the Chord function more useful than a simple 'auto accompaniment' facility - providing a means of playing complicated chord sequences live, for example.
The Arpeggio function generates arpeggios of all held notes, or chords generated by single keys if Chord play is selected. The order in which the notes are played can be set to up, down, up then down, or random, and a playback rate also specified. The bonus with the U20's arpeggiator is the ability to assign a transmit channel for arpeggiated notes independently of the 'normal' keyboard transmit channel, so that one sound can be used to play a sustained part, whilst a second sound arpeggiates automatically.
Unfortunately, the arpeggiator does not generate or synchronise to MIDI clock data, which would undoubtedly have made it a more professional feature. As it is, it remains primarily a compositional aid.
Keyboard and Sound Patches can be selected independently or together: in Link play mode, selecting Patch 53 with the Bank and Number buttons will select both Keyboard Patch 53 and Sound Patch 53. Consequently, it makes sense for the user to create Keyboard Patches that are suitable for playing their numeric Sound Patch equivalents, and controlling their parameters with the front panel sliders, and then select these Patches together. Alternatively, the two sets of Patches can be selected independently in Sound play and Keyboard play modes.
I've made a lot of references to the U110 in the course of this review but I feel they are justified, given that the U110 is a valuable point of reference for the U20 and that it illustrates just how much better the U20 is in many respects.
The U110 was/is a good idea - a multitimbral replay-only sample module crammed full of ready-to-use instrument sounds - but it is let down by poor sound quality and an awkward voice allocation method. The U20, on the other hand, offers a sound quality that is in a different league entirely, has added another 30 or so Tones to extend the range of basic sounds, employs dynamic voice allocation, and the signal processing section is far more versatile with independent chorus and reverb effects possible.
With six instruments and one rhythm part, 30-note polyphony and built-in effects, the U20 has all the sounds that you might need to create complete tracks. And although this is by no means unique to the U20, it distinguishes itself through offering a very good selection of sampled instruments, and reducing to an absolute minimum the amount of trouble needed to use those sounds.
From this description, the U20 could be merely a U110 with a keyboard, but as it happens the instrument has facilities that make it more than this. Real-time control over sound parameters and the ability to generate controller data from the front panel sliders both help in this respect, and 64 Patches to store and recall all aspects of the U20's control facilities make the instrument an attractive choice as a master keyboard.
£1050 inc VAT.
Roland UK, (Contact Details).
Review by Paul Ireson
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