There are four LFOs in each voice, each of which provides four frequency ranges from Slow (0.001Hz to 1Hz) to High (1Hz to 1kHz) and can be synchronised with the Master Clock. Each offers a rate knob, a button to select from four initial waveforms, and a dedicated destination button that provides a shortcut to creating a modulation path. But, as always, it's when you press the More button that things become really interesting. Perhaps most importantly, this adds a Variation parameter that allows you to morph the triangle wave into a sine wave, adjust the duty cycle of the pulse wave, morph the sawtooth through a triangle to a ramp wave, and morph the S&H wave into white noise. Additional parameters include key sync, the Start Phase of the LFO cycle, delay of up to 10s, fade in of up to 10s, fade out of up to 10s, an option to limit the number of LFO cycles to a number between one and 32, and a 6dB/oct low-pass filter to smooth (slew) the waveforms. You can also decide whether the resulting waveform is unipolar (always greater than zero, like a guitarist's vibrato) or bipolar (centred on zero). This is a huge package of valuable features for a humble LFO.
Be glad that there are still companies that are willing to invest the vast amounts of time, effort and money to design and build magnificent/crazy/imperfect/wonderful instruments like this. It would be a sadder world if they didn't.
There are three primary contour generators per voice, named Filter Envelope and Amplifier Envelope (because these are their preset connections) and Modulation Envelope. All three are presented on the control panel as ADSRs, but pressing their More buttons reveals eight further parameters, including delay and hold stages (each ranging from zero to 10s) that turn them into six-stage DAHDSR contours. The responses of the attack, decay and release phases range from 1ms to around 10s, which is nice and snappy at the fastest extreme, although rather too rapid at the slowest. However, a Time Scale parameter is also provided, and this allows you to shorten or extend these times by factors in the range 10 percent to 1000 percent. This is invaluable when programming acoustic type sounds because you can use the keyboard position to control the Time Scale, making lower notes speak more slowly and higher ones speak more quickly. Further parameters include legato reset (re–initialise the contour at zero when a new note is played, or pick up from the current position), and Velocity Modulation Amount. Best of all, the shapes of the attack, decay and release stages can vary from logarithmic through linear to exponential. The shapes of contour stages make a huge difference to the nature of the sounds that you can obtain from a synthesizer, and being able to program them individually is a treat — not unique to the One, but very welcome indeed.
Alongside their dedicated destination buttons, the contour generators offer buttons for Multi Trig, Sync, Loop and Latch. The first of these toggles between single- and multi-triggering, while the second allows you to determine the durations of the D, A, H, D and R stages using the Master Clock, allowing you to synchronise the contours with the LFOs, effects, arpeggiators and sequencers. Looping does what you might imagine but, while the manual describes the output as a trapezoid, that's (usually) incorrect because only a looped HASR contour creates a trapezoid shape. Finally, Latch holds the contour voltage indefinitely at the sustain level if Loop is off, or allows it to loop indefinitely if Loop is on.
The One's top panel offers controls for a number of fixed modulation paths, and the quick assign method allows you to create modulation paths by pressing the Destination button in a given module or any of the buttons in the Expression Assign panel followed by adjusting any suitable top–panel parameter. But the real modulation power lies in its modulation matrix. This offers 20 slots, each with four assignments — Source, Controller, Transform and Destination — and their associated values. There are 26 Sources, and the inputs from these can be modified using any of 26 Controllers — things such as the wheels, the pad, velocity, aftertouch, contours, LFOs, external CVs and more. The signal then reaches the Transform section, and this offers a choice of four mathematical transforms to further modify the modulation shape. Finally, you can choose from 90 Destinations. The modulation level parameter found in the Source setting is then applied at the end (rather than the start) of the chain, ensuring that delicate modulations are not adversely affected by quantisation and calculation noise as they pass through the Controller and Transform stages.
The One allows you to name, add notes to, and save modulation matrix presets. Recalling these later — either to replace all of the existing slots in a Timbre or to add them to any that already exist — is then equivalent to being able to press a button and have all of the cables on your modular synth jump into the right sockets and magically turn the appropriate knobs to the right values. If there's a shortcoming here (and there is) it's that the oscillators aren't sources in the matrix, which precludes audio–frequency modulation of most parameters. I can speculate why this is — the One may not have the power to convert audio signals to high sample–rate sources and then perform the relevant mathematical operations — but it's a shame nonetheless. If I'm wrong, I hope to see them added at some point in the future.
Everything discussed so far has pertained to an individual Synth, and a Preset can comprise any combination of the three Synths provided. You can switch each of these on or off in the Keyboard Control section and, when on, determine the range of keys over which it's played. This allows you to create layered sounds as well as splits. You can transpose individual Synths in the range ±12 semitones, but I think that this is inadequate; a minimum of ±24 semitones is required to make full use of splits on a five-octave keyboard.
There are now three further signal stages to be found in the Preset level. First comes the Master Effects section. This offers two inputs, two processors and two outputs, all of which you can configure as a single stereo processor or as two single-channel processors. In the latter mode, you can configure the two processors to act in parallel or in series, you can inject the audio into the first or the second or both processors in any proportions, and you can determine how much of the output from Effect 1 is passed to Effect 2. (This is much the same as the architecture of the two filter sections.) If you have programmed a pan position in the Timbre, the dry sound will still reach the One's outputs unscathed but, for obvious reasons, the pan is discarded in the Master Effects busses when in single–channel mode.
The list of Master Effects types is the same as that of the Synth Effects, but with the omission of the vocoders and the addition of five Eventide reverbs. You can place these reverbs in either of the Master Effects slots alongside one of the non-Eventide effects but you can't invoke two Eventide effects simultaneously. The rest of the Master Effect facilities — naming, saving, recalling and so on — are (where appropriate) identical with those of the Synth Effects. One unexpected benefit of this is that, in many cases, you can save a Synth Effect and recall it as a Master Effect, and vice versa. However, you can't reassign the two knobs in the Master Effects' physical control panel; these always control the signal level of the two Master Effects inputs.
After the Master Effects there are four Insert busses accessed using the More button in the Output section. (The manual states that they sit after the Synth Effects, which is true, but not explicit.) You can use each of these as an auxiliary output, directing each Synth to a separate channel on your external mixer, recorder or workstation, or as an effects loop, using a TRS Y–cable to direct a Synth to an external device and then receive the result back at the same socket. If the external device is mono–in/stereo–out, the return can be received using adjacent (1+2 or 3+4) sockets, and the stereo panorama will then be retained. A given Synth can only be sent to one bus at a time, and a given bus can only host one input at a time, but you can also direct external audio signals to busses 3 and 4 respectively. These assignments are saved and recalled as part of each Preset.
Following the Insert busses, you can determine which Synths are directed to the Main/Headphones and/or Sub outputs. (Synths can be directed to both outputs pairs simultaneously if desired.) You can control the levels of the three sets of outputs independently: the Main L‑R and Headphones outputs have knobs on the Output panel, while the level of the Sub L‑R pair is controlled by a More page parameter.
The Main and Sub output VCAs have noise reduction applied to them, and this offers settings ranging from 0dB (no noise reduction) to -24dB (the One should be virtually silent between notes). By default, this is set to -12dB, which works well in most instances. However, there are some in which it does not. To illustrate this to Moog, I programmed an electric piano Timbre that used an LFO directed to the levels of the output VCAs to create tremolo. When playing this, I could hear three or four quiet but distinct thumps generated at the LFO rate after each note. Experiments revealed that these were created when the modulated output from the VCAs poked out above and then dropped below the noise reduction threshold. This left me with two options: program the tremolo in a different way, or defeat the noise reduction and live with any resulting hiss. I opted for the former. While investigating this, I also discovered that the noise reduction can remove the clicks from the starts of notes with the fastest attack times, suggesting that it responds more slowly than the contour generators. When I raised all of this with Moog's engineers, they told me that the noise reduction algorithm is still subject to improvement.
I've mentioned the Master Clock on numerous occasions already, and this is another resource provided at the Preset level. Many of the time-dependent facilities within each Synth — its arpeggiator, sequencer, LFOs, contours, and the timing parameters within certain effects — can be synchronised to this at the same or different ratios to create coherent effects. Unusually, the clock offers swing, and you can even nudge and bend its tempo in real time from the front panel, which is something that I don't remember seeing before. You can also sync to an external (analogue or digital) clock if desired.
The One boasts good performance capabilities. Starting with the keybed, this is the semi-weighted, 61-note velocity- and aftertouch-sensitive Fatar TP-8S, versions of which were used in the John Bowen Solaris, the Kawai K5000, the Novation Supernova II and the Waldorf Wave. It's pleasant to play and it offers five velocity curves that you can select on a per-Synth basis, which means that you can layer multiple sounds with different responses to create dynamic changes in their balances. In addition, you can alter the key-track pivot note on a per-Synth basis, but I'm not sure what this achieves that can't be programmed using other functions. The One also offers three note priorities in monophonic mode (lowest, highest, most recent) that, coupled to the triggering options, makes it possible to emulate almost any vintage monosynth. Currently, there are no selectable aftertouch curves, nor does the One respond to poly-aftertouch over MIDI, but I suspect that these are in development.
To the left of the keybed, the performance panel offers a pitch-bend wheel and a modulation wheel that's heavy enough to stay in position if you take your hand from it. Next to these, you'll find octave shift buttons and an X/Y pad with an associated Hold button. You can assign the X and Y destinations in the modulation matrix, but the pad also generates an assignable gate when you touch it, and it's pressure-sensitive too. You can place the zero point of the pad to be at its centre or at its bottom left-hand corner; the first allowing both positive and negative values to be generated, while the second allows positive values only. You can save and reload existing mod–wheel and pad positions as part of a Timbre. The controls for the portamento/glissando function are also found here. This can be gated by the keyboard and, when used with a monophonic Timbre, can be permanently on or invoked only when you play legato. Three glide curves are provided and these produce the usual, distinct effects.
Despite its complexity, the One is user-friendly. In part this is a consequence of the spacious control panel, but the fact that you can turn one knob without bumping another doesn't tell the whole story; the layout is intuitive and you'll find yourself whizzing around it in no time. Then, when you delve into the programming and housekeeping systems, you'll also find these to be surprisingly simple to use.
Before starting to use the One, you should visit the Settings pages to configure things such as the knob mode (absolute, pass-through and relative modes), the screen and LED brightnesses, how Presets are loaded, the keyboard response curve, the noise reduction threshold, the fan mode, various import and export parameters, the MIDI I/O options and the analogue control inputs and outputs. Having done so, you'll be ready to return to start programming and playing.
The most visible of the housekeeping functions is the Preset Browser, which allows you to allocate your Presets to Categories, Moods and Groups as well as to a Type (Single, Split, Layer and Multi) so that, once saved, you can find them again according to each of these criteria. This isn't a trivial point; the One can store a huge number of Presets and, as your library grows, you'll want to use these attributes to avoid scrolling through hundreds of sounds to find the one you want. You can also save Notes within a Preset using either the One's own keyboard or an attached ASCII keyboard, which is, of course, much faster. If I were using the One as a live instrument, I would use these Notes as crib sheets and for lyrics. You can also save individual Timbres together with their Notes, whereupon they're saved as Synth 1 of a new Preset that the One creates specifically for this purpose. When it comes to reloading saved sounds, you can either recall an entire Preset or load a saved Timbre into the active Synth in a Preset that you're editing.
For live use and self-contained projects, the One offers 128 Performance Sets that can each contain up to 64 Presets. Assigning Presets to a Set is as simple as pressing and holding the bank/location buttons (A-H, 1-8) that define its location within it. Then, once you've created a Set, you can store it with a name and text notes that, years later, will remind you why you did so and how it was intended to be used. Of course, it would be hard to keep track of everything in a Set if the only things that identified its sounds were their alphanumeric locations, but you can switch on an invaluable option to display the names of the eight Presets in a bank when you select it.
Behind the Browser and the Performance Sets lies the Library, which, amongst other things, allows you to export Presets, sequences, Performance Sets, programmed effects, modulation matrix presets, and global settings to USB memory sticks. I had a 2GB stick plugged in throughout this review and, when I wanted to transfer a Preset from the One in my studio to another at Moog's factory in Asheville, I just moved the stick to my MacBook Pro, dropped the file into an email and, a few moments later, someone on the other side of the pond was able to duplicate what I was doing.
Other library functions include the creation and management of new Categories, Moods and Groups as well as something called User Spaces. The manual makes a big deal about the ability to export complete User Spaces to a USB memory stick, and it's right to do so. This is the equivalent of saving a complete instance of a given One (not just the sounds, but the whole setup) that you are later able to load into another that then 'becomes' the first instrument. If you're touring, this will be a boon. Carry nothing more than a USB stick, hire a local One, load your User Space, and it will be no different from the synth back in your studio. Your tour management company will love you!
Like many polysynths, the One offers a Compare button that allows you to compare the current edit with the saved version of a Preset. But I'm more impressed with the hugely useful Snapshot function. If you press this at any time while editing a Preset, all of the current parameters, together with any Notes that you have added, are saved in a time-stamped version of that Preset. If you then edit yourself into a cul de sac, you can view the Snapshots and return to any that you choose, either to overwrite the current Preset, or to save it as a new Preset, or to continue editing from the point before you turned up the blind alley. You'll also find entries in the Snapshot list called Autosave, and these are added by the One whenever you do something significant such as altering the shape of the modulation matrix or the effects in use. The same mechanism is also available for sequences, where it will again be invaluable.