John Bowen Synth Design Solaris
February 14, 2012
By Geary Yelton
John Bowen has been at the forefront of synth and sound design since the early ’70s, contributing to synths from Moog, Sequential Circuits, Yamaha, Korg, and Creamware. In 2007, he began demonstrating his own prototype, the Solaris—one man’s dream of the perfect hardware synthesizer. After years of anticipation and collaboration with German manufacturer SonicCore, his dream is now a reality.
Think of the Solaris as a virtual modular synth that you patch using the internal software rather than a fistful of cables. Indeed, if it were a modular system, it would be humongous, with four oscillators, four filters, seven envelope generators, and five LFOs offering greater complexity than off-the-shelf hardware synths. Playable controllers include a 29-inch ribbon, an X/Y joystick, and enough front-panel knobs and buttons for fast access to more than 1,250 parameters. The 61-note synth-action keyboard supports velocity and channel aftertouch. Real wood side panels add a touch of class.
Although it can sound so convincingly analog that the first time I powered it up, I thought it was, the Solaris is completely digital—which lets it change personalities to suit your needs. Several synth architectures are available, including three types of vintage analog modeling, sample playback, and vector and wavetable synthesis. For effects, you get delay, chorus/flanger, phaser, and three-band EQ.
The Solaris is not multi-timbral; you can’t play more than one preset at a time, and it doesn’t receive on multiple simultaneous MIDI channels. Bowen hopes to add a four-part multi-timbral mode someday. Polyphony is ten voices—not generous by modern standards, but the Solaris’s 32-bit, 96kHz audio engine gives it a pristine sound that sparkles with personality.
Bowen says polyphony could double with an OS update.
The Solaris stores all presets, samples, arpeggio and sequencer patterns, and the operating system on a CompactFlash card. CompactFlash has been around since 1994, and though it’s ceded popularity to the SD format, it’s still robust. With a suitable card reader, you can hook up to your computer to back up all your patch data or install OS updates you’ve downloaded.
The Solaris’ front panel has six backlit mono chrome LCDs. The main display’s contents are controlled by a row of buttons above and two rows of knobs below. Then, five two-line text displays and their associated buttons and knobs are each devoted to one or two building blocks of synthesis: oscillators, LFOs, envelopes, and so on. One display lets you instantly access four filters and four amplifiers, and another handles four mixers and four insert effects. All these dedicated displays are a brilliant solution to the age-old question: How can you quickly change dozens of parameters without scrolling through dozens of pages?
By default, the main display shows the current preset. Access to arpeggiator, sequencer, ribbon, output, and effects parameters is just a button-press away. Each text display has just two modes: “Main” is where you set basic parameters for each section—filter type, cutoff, and resonance, for example—and “Mod” lets you dial in modulation sources. If you want to route four sources to filter parameters, you can choose from dozens of modulators, specify another source to modulate the modulator (e.g., the mod wheel governing the depth with which an LFO varies the filter cutoff ), and select cutoff or resonance as the destination.
In addition to the buttons and knobs surrounding the display, other buttons access functions such as turning the arpeggiator and sequencers on and off, turning the four mixers on and off, bypassing the effects, and performing utility functions. I especially appreciated the Undo button, which returns the most recently changed parameter to its previous value.
Oscillators and Filters
Much of the Solaris’ versatility lies in its four multiple-personality oscillators, each generating six types. The MM1 multimode type, for example, models waveforms ranging from old-school analog to sine waves that morph continuously into sawtooth or pulse. Variable waveshapes are so precise that you can dial up a pulse wave with a width of just one percent. The “Jaws” waveform stacks seven detuned sawtooth waves, obviously emulating Roland’s SuperSaw. You can also specify a waveform’s beginning phase and hard-sync any oscillator to another.
Other oscillator types emulate specific vintage instruments. The CEM (Curtis Electromusic) type emulates the Sequential Circuits Prophet-5, and the Mini type nails the Minimoog sound. When I compared it to my Moog Voyager’s output, I was impressed by its accuracy, but not at all surprised—Creamware’s Minimax is still one of the best virtual Minimoogs out there, and it’s part of the Solaris’s DNA. [Hardware that still runs Minimax and other Creamware-derived plug-in synths includes the Use Audio Plugiator, reviewed July ’09, and SonicCore’s new SCOPE system, to be reviewed next month. —Ed.]
VS Vector Synthesis borrows its 94 single-cycle waveforms from the Sequential Circuits Prophet-VS. (Bowen created most of them when he worked for Sequential in the ’80s.) This was the first synth that used a joystick to crossfade between oscillators—a technique called vector synthesis, which was later adopted by the Korg Wavestation. Similarly, the Wavetable oscillator type borrows 64 wavetables from Waldorf’s vintage MicroWave, itself a descendant of the classic PPG Wave synth, which could step through dozens of waveforms in rhythmic fashion to produce very dynamic sounds. So in addition to no-compromise virtual analog synthesis, you’ve basically got a Prophet-VS and a PPG inside the Solaris.
Another oscillator type plays user samples. You can load your own sample data in WAV or RAW formats to the Solaris’ CompactFlash drive, but you’re limited to a single sample for each of the four oscillators. An update could deliver true multi-sample mapping someday, but the Solaris can modify and mangle audio in so many ways that its user sampling is still quite useful.
The Solaris is the first synth I’ve seen that implements the concept of Rotors, and I don’t mean a Leslie speaker effect. A Solaris Rotor is a mixer that cycles between its inputs at a rate determined by a control oscillator. Each of the Solaris’ two Rotors has four inputs that can be any audio or control source. You can either switch between inputs instantaneously or crossfade between them. Because the control oscillator extends from LFO to audio-range rates, you can shift from four-step wave sequences to audio waveforms that are rich in sum-and-difference tones (that’s why the rotor controls are in the oscillator section). In short, Rotors let you program animated sounds you’ve never heard before.
Each of the four filters is a master of disguise. At one moment, it’s multi-mode, with a huge selection of types and cutoff slopes; at another, it’s accurately emulating the Prophet-5, Oberheim SEM, or Minimoog filter. The vocal formants setting very effectively re-creates five vowel-like sounds, and you can shift between them with the joystick. The comb filter setting delays the signal to create a feedback or feed-forward loop and is useful for simulating plucked strings and more off-kilter sounds. Plus because you can route any combination of filters in series or parallel and
dynamically modulate them, you can build very complex, constantly shifting sounds.
The Solaris can process external audio routed through either its 1/4" inputs or its S/PDIF port. Among other things, you can filter them, apply effects, or use them as inputs for the Solaris’ envelope follower.
LFOs and Envelopes
Like a modular synth, the Solaris lets you use almost any signal as a modulation source, with three or four possible sources for each destination.
Normal functions offer greater complexity than those of off-the-shelf synths; for example, the multi-waveform LFOs extend well into the audio
range: up to 500kHz. You not only get four LFOs that can modulate practically anything, but a fifth LFO dedicated to vibrato. You can delay LFO start times, specify phase angle and fade-in and fade-out times, and even route three more sources to modulate each LFO.
With seven envelope generators, the Solaris enters the sound-shaping realm of more complex soft synths and large-scale modulars. At fast settings, the envelopes are impressively snappy. Six of them add an initial delay stage that can postpone the attack as much as 20 seconds. You can apply velocity, the mod wheel, key tracking, or any of four external MIDI CCs to modulate the attack, decay, and release times and sustain level. Five envelopes are freely assignable; the sixth is dedicated to the four VCAs.
The seventh generates a loopable two-way envelope and offers even more flexibility. You can determine the loop’s start point and which stage plays when you release a key. You can also specify and modulate the levels and times for each of eight segments. This is useful for creating vector synthesis patches with droning oscillators and for playing through wavetables in real time.
Controllers, Arpeggiator, and Sequencer
Just above the pitch and modulation wheels, the joystick can control almost any two parameters (one for each axis) in real time. Its primary purpose, though, is to crossfade between four sound sources—the basis of vector synthesis.
The assignable ribbon can control two parameters simultaneously when you use two fingers. You can set its zero point as either the center or the left edge, or have the zero point reset to wherever you first touch it. A hold function maintains the ribbon’s effect on the sound even if you remove your finger. Ribbons are most often used to bend pitch, and this one lets you bend to any interval, even beyond the range of hearing. Two improvements I’d like to see: I wish you could program the rate at which the ribbon’s value returns to zero, and I wish it could change values in discrete steps. (Applied to pitch, this would sound like a glissando as opposed to smooth portamento.)
The arpeggiator offers touches such as varying degrees of swing, a 32-note maximum length, and beat resolution ranging from a 32nd-note to eight measures. Though it can store 64 patterns, only four were loaded in my test unit. Editing software for the arpeggiator and sequencer is in the works, and more factory patterns will be preloaded in future units. In the meantime, the Solaris’ display is large enough to make editing a snap.
The analog-style step sequencer has four rows (or tracks, if you prefer) for controlling oscillator frequency, note velocity, or any other modulation destination. Sequence length can be anything from one to 16 steps, and each row can be a different length. Because each sequence is a modulation source, you set up its routing at the destination. For example, to control oscillator pitch, you specify a sequence as a mod source in the oscillator section. Once that’s done, you dial in the value of each step in the main display. This scheme isn’t particularly intuitive, but it makes sense once you get used to it and allows for tremendous flexibility.
With the sequencer enabled, any note you play will trigger the sequence. When you hold down a chord, each note in the chord follows the sequence. Unlike with the arpeggiator, though, you can’t press Hold to keep a sequence repeating.
The Solaris has four banks with room for 128 presets in each. You can store up to 128 banks on the CF card. My review unit came with 350 ready-to-play presets and a few more intended as templates for programming your own sounds. John Bowen expects more to be available soon. Sounds range from soothing and ethereal to ballsy and downright twisted. Basses of all descriptions are in ample supply, and thick string pads are also abundant. Authentic-sounding Minimoog-style leads are especially plentiful, too. You’ll also find quite a few excellent presets that show off the arpeggiator. Because most factory sounds emulate analog synths, you won’t find realistic emulations of acoustic instruments, and that’s just fine with me.
More than any other synth, the Solaris reminds me of one of my all-time favorites, the Oberheim Matrix-12, in both its physical appearance and its routing versatility. But it goes way beyond the Matrix into territory previously explored only by modular synthesists. Despite the Solaris’ complexity, its comprehensive and well-designed user interface makes it relatively easy to program once you learn your way around.
Although the Solaris is totally based on digital signal processing, it certainly sounds like an analog synth. Given the Prophet-VS and PPG-like modes, it can sound digital as well, but its extended audio specs give even its digital waveforms a warmth (for want of a better word) that no other digital synth I know achieves. Sure, it’s a boutique instrument with a price to match, but it definitely stands out from the crowd. If you want to as well, get your hands on one.
PROS Wonderful sounds. Exquisite audio quality. Multiple synthesis types and extremely flexible modulation routing. Plenty of visual feedback and hands-on control.
CONS Not multi-timbral. No true multisample mapping. Limited polyphony. Expensive.
POLYPHONY 10 voices.
SYNTHESIS TYPES Virtual analog, wavetable, vector synthesis, user sample playback.
WEIGHT 33 lbs.
As the Oberheim Matrix-12 was to the ’80s, the Solaris is to today, only far, far deeper. To see it and hear it is to want it.
***Audio clip examples of the Solaris synthesizer.