Review: Ploytec PL2 Synthesizer

Tiny synth with a huge sound

Fig. 1. The Ploytec PL2 provides a range of intense synth sounds. Small and lightweight, it can be conveniently attached to any controller or instrument. I HAVE to keep reminding myself of the many surprising sizes and shapes synthesizers can take: A modular synth, for example, can span an entire electronic music lab. In contrast, the Ploytec PL2 synthesizer (which is, admittedly, not nearly as complex as a full-blown modular) is not much bigger than a gift box for a ring, yet it puts out some of the fattest, rudest tones possible (see Figure 1). And although its surface is too small to accommodate more than a single RCA audio output, MIDI input, and USB port, the programmable parameters are remarkably rich.

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Squaresville With a footprint of less than a square inch and no front-panel controls, the PL2 handles programming, and setup happens via MIDI within the freeware editor (see Figure 2), which you can download at the Ploytec website. Because of its light, plastic build, I frequently pulled the synth off of the desktop with the weight of the MIDI cable. You’ll need to affix the PL2 with double-sided Velcro or something similar. On the other hand, it is small enough to attach to the side of my MIDI guitar or sit on top of my half-rack Axon MIDI converter.

The PL2 draws power from its MIDI connection; no wall warts or other transformers are needed. You can also supply power through its USB mini-B jack using a wall-plug adapter or by connecting a USB cable to a computer. I set mine up on my desktop with the unit plugged into the MIDI Out of my Novation SL61 MKII keyboard controller, which, itself, was powered via USB. Templates for a wide range of controllers (including those by Behringer, Korg, Novation, Roland, Terrasoniq, Yamaha, and controllers for TouchOSC) are available online.

Editing Ploys There is no MIDI Out or Thru on the PL2, so the usual handshake protocols between MIDI devices isn’t necessary to program sounds. It’s understandable that, given the unit’s limited real estate, it doesn’t allow for the extra MIDI ports.

You get 32 preset locations and another 32 user slots. An additional 64 slots provide an assortment of random sounds, many of which are throwaways. Patch edits are created and stored in the user area only, so any tweaks made in the first 32 presets must be copied to the user locations in order to preserve them. You do this, sensibly enough, by hitting the Store button, or as soon as the unit receives a MIDI Program Change message from an external source such as a controller or sequencer. Program Changes issued directly from the editor, however, will reset the patch, but when receiving an external Program Change from a controller or DAW will store your work. You can of course, save the patch to disk for later recall—something I’d advise doing if you’re attached to any of your tweaks.

A pair of tabs at the top of the window shuttle you between the editor and the setup screen. The setup screen also provides a firmware update page. There is no help or manual provided for the editor, and there is no handshake and no real confirmation that the editor is connected or the firmware updated; pressing the Firmware Update button will result in a successful firmware update message, even if the synth is not connected. At one point, the software lost contact with the instrument, and although everything worked fine in the DAW, I could not affect any changes in the instrument or trigger from the preset tests in the editor.

Fig. 2. A view of the two editing screens for the PL2. Although they indicate what the synth is capable of, they can also be somewhat misleading at times. The lack of editor documentation doesn’t help. Although the manual for the synth states that it only receives on MIDI channel 1, with the version 2.0 firmware update, the editor lets you change reception to other MIDI channels. You can accomplish this by setting the new MIDI channel, checking the Use Extended Features field, and then hitting the Update Features Only button.

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In the editor, you’ll find parameters for MIDI output where none seemingly exists. In fact, they designate a separate MIDI output for the software.

Topology The editor still provides a good indication of the PL2’s sonic capabilities, and they are pretty impressive. The synth has two analog oscillators that share an ADSR envelope generator. A button at the bottom of the editor lets you link the ADSR to the filter or disengage it. Technically, both oscillators start off with the same square wave, and each Waveform selection from the pull-down menu imparts a slightly different pre-filter modulation scheme.

Access the first four waveforms by selecting Normal mode in the editor; the waveforms include a square wave with pulsewidth modulation (PWM) controlling both oscillators. The second waveform choice allows independent square-wave modulation over the oscillators with PWM 1 and PWM 2 parameters. The third and fourth waveforms allow more complex adjustments of the waveform by splitting changes on the duty cycle of higher and lower frequencies in different directions. The oscillator mode pull-down menu offers Mono (one oscillator), Poly (two notes), Dual (a detuned pair), and Octave, which sets the oscillator pair one octave apart. Dual mode produced sounds with enormous girth, and tying the resonant filters to the envelope generator produced delicious animation. (Audio examples are available at; here, reference Clip 1.) The PL2 has no built-in effects processors.

The firmware 2.0 update provides, among other improvements, four additional waveforms. The first is an analog kick-drum waveform. Here, the PWM controls can alter timbre and attack parameters, and the DC offset changes the release. That’s not very intuitive, but again, an editor software update can change that. It’s anyone’s guess what the remaining waveforms are, as they are documented by name only. The best description I can provide is that the second and third are spiky and somewhat nasal sounding, a bit like a clavinet, and the fourth has pronounced harmonic overtones, sounding like a chord.

The PL2 features a resonant, 2-pole, state-variable digital filter (useful for taming aliasing), followed by an analog lowpass filter. The digital filter’s DC offset parameter in Normal mode helps create clipping effects, roughs up the tone, and increases the raunch factor considerably (reference Clip 2).

The new 2.56 firmware update (released at Summer NAMM but unavailable for this review) includes a vocal-tract modeler offering formant sounds and synthesized speech—a tribute to the General Instruments SP0256-AL2 chip of the early ’80s. You can play the allophones (speech elements) on the keyboard and control the notes via the modulation wheel, or the other way around. Select between alphabetical or original order, or use a button controller, such as the Novation Launchpad Mini, to access all 64 allophones.

Attention, Shoppers If you’re looking for silky strings, polished brass, or smooth pads, you’re in the wrong aisle. Though you can tame the PL2’s oscillators into more polite timbres, its stock-in-trade are rough, edgy sounds on the edge of stability that will spit, howl, and bite. If you like sounds in which aliasing is deliberately part of the package, this synth is for you.

The PL2 excels at creating eerie drones, growling basses, and stinging, distorted leads. The Kick Drum oscillator is nice and punchy. As a mono lead synth or bass, it offers adjustable portamento, but legato mode is strangely absent. Otherwise, practically every parameter has an associated (but fixed) Control Change message, and therein lies my plea for a plug-in version of the editor, which would make automation that much easier.

I have serious reservations about the PL2 editing software. Moreover, there are holes in the synth’s documentation, and without a user manual for the editor, learning many of the parameters (in particular, as they apply to the different oscillator modes) is a shot in the dark.

Still, I’d recommend this synth. Priced below $100, the PL2 is an irresistible bargain and a welcome addition to tracks that need a little tough love.


STRENGTHS Fat, flexible, rough, and animated sounds. Pocket-sized. Analog filter.
LIMITATIONS Software editor has no documentation.

$99.95 street