- One of the most innovative names on the plug-in development block is French company XILS Lab, whose VCS3 clone I ran the rule over last year. This time around, it's the turn of the PolyKB II which continues the development of XILS' real forte: the modeling of rare but wonderful sounding synths. PolyKB II's sound captures the spirit of the RSF PolyKobol Analog Synthesizer and, even if that name doesn't resonate with you in the same way that titles from Moog or Sequential Circuits might, don't be fooled into thinking that this 21st century take isn't capable of phenomenal results.
As its name suggests PolyKB II is the second incarnation of this plug-in, the original having been released in the autumn of last year. This newer version irons out glitches in the original and adds serious functionality. I'm guessing, though, that most people reading this won't be fully familiar with the PolyKB concept, so let's start from the beginning.
The right hand side of the main GUI will make sense to anyone familiar with subtractive synthesis techniques. There are two multi-waveform oscillators with their own tuning frequency dials and on/off switches, while the resonant filter section lies to the right, complete with a drive setting to add extra character. Two freely assignable envelopes lie further to the right and as we'll see shortly, PolyKB II's modulation possibilities are comprehensive. Below this lie on-board effects in the form of delay, chorus, phaser and EQ, each of which features control knobs and an on/off button. Clicking an effect's name launches a larger control set with parameters tailored to type.
The bridge between these synth functions and the modulation section comes in the form of LFO 1, which offers multiple waveforms plus delay and fade dials to further control capabilities here. The standout features of this otherwise familiar control set are the oscillators themselves, which allow for intermediate placement between waveforms to create hybrids. Ally these to envelope or LFO routings which "scroll" through the available options and the sonic results are hugely varied and powerful. Add in the optional noise generator and the raw sound is excellentïrich, full and capable of a wide range of sounds.
The central section represents PolyKB II's Modulation Router and this has been significantly enhanced from Version 1's equivalent. Destinations can be selected in two ways with red and green LEDs lighting to show positive or negative polarity; in other words, were you to route velocity to the filter cutoff, a red "negative" routing would make stronger notes trigger duller sounds, while a green "positive" routing would mean stronger notes producing brighter ones. Control sources are provided in MonoMod, PolyMod and Sensitivity sections, with LFO and noise generators in the first category, the second ADSR envelope and oscillator 2 in the second and after-touch and velocity in the third. Below this, there are separate, open-ended routing options where you can choose from a wide variety of both sources and targets from a drop-down menu and then use control dials to decide how much each routing will affect its destination. This section, as you might have guessed from the description, is comprehensive, and a huge amount can be achieved here to create anything from gently undulating sonic evolutions to full-on chaos.
PolyKB II's most unique features are in the curiously-titled Programmation section, which features a full-featured step-sequencer, capable of generating patterns of up to 128 steps in length. It gets betterethe sequencer is polyphonic, so it's even possible to program and generate up to eight voices from a single step, to trigger a serious chunk of backing track from a single key (making the absence of a standalone version something of a frustration, it must be said). The sequencer features its own transport controls to allow you to record sequences and once you have, there's a pop-up window to show how your results slot into the sequencer's grid lines. Fortunately these are zoom-able as the default setting is small and this is a criticism to be leveled at PolyKB II in generaleexpect to spend some time peering hard at the labeling surrounding several parameters.
Back to the sequencer, the DynaMYX display module lets you take each active voice and place it in the stereo field via two virtual microphone pickups, creating some extraordinary spatial effects. Each voice is represented as an LED blob and dragging these around in real-time allows you to experiment with spacing and distance. You can and will lose hours heresbut it's time well spent as this really is a programmer's dream. If more straightforward arpeggiation better matches the sound you're after, the plug-in provides this too, with variable direction, octave, gate, rate and swing values to bring chords to life. Finally, the output section allows you to switch between mono/stereo output, set pitch-bend range, global velocity sensitivity and after-touch (Pressure) amount.
This is a deep instrument but it's rewarding too; while you'll need time to get your head around the layers of sonic potential, you'll make some great sounding "mistakes" along the way. Once you do familiarize yourself with the features, this is an instrument which will appeal hugely to those who like to combine in-depth programming with production. It's capable of everything from stark and hard to mellow and warm, with plenty of whizzes and bangs in between I can't really think of an electronic sound-type PolyKB II isn't capable of taking on. If the sonic potential appeals but this simply looks too involved for your tastes, the PolyKB II Player, at just 39 euros, might be more your thing. It features the same factory sounds but limits editing options considerably to a handful of knobs and buttons, very much in the mould of Arturia's Analog Experience products. I'd urge you to consider the full version thoughiit's one of the most rewarding soft synths I've played.
Ratings /
Cost: 4/5
Versatility: 4.5/5
Ease of use: 3/5
Sound: 4.5/5