Review: Roland System-1m

Semi-modular plug-out synth for the desk or rack
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It has taken a surprising amount of time for major manufacturers to trust that the modular synth renaissance is not a short-lived fad. But when Roland joined the fray, it did so with a vengeance, going fully analog with its upcoming American-made line of System-500 modules and offering a set of hybrid Eurorack products based around its innovative Aria technology—Demora, Torcido, Bitrazer, and Scooper—that feature a highly programmable digital core complemented by voltage-controllable parameters.

The most sophisticated of Roland’s modular offerings, however, is the System-1m, a semi-modular synth that takes the basic features of Roland’s flagship Aira System-1 keyboard and extends the control possibilities. Consequently, the System-1m is designed to meet the needs of a wide range of synth users—from keyboard players and DJs to sound design pros. Moreover, it can be set up flat or angled on the desktop, or housed in a traditional 19-inch, 3U rack or Eurorack case.

If you are familiar with the Aira System-1 keyboard synth, you will immediately see a resemblance in the System-1m’s front panel and overall architecture (see Figure 1). Like its keyboard-based sibling, the System-1m can be used as a 4-voice polyphonic synth. It utilizes the Aira ACB (Analog Circuit Behavior) technology, and it can host any synth from Roland’s growing list of Plug-Out software-based emulations. Among the things that are not present on the semi-modular version that the System-1 provides are the Scatter effects and the arpeggiator. (For a full review of the Aira System-1, visit

The main difference in using the System-1m with the Plug-Out synths, of course, is that you get the enhanced flexibility that CV and gate patching offer. Yet the System-1m remains easy to use, making it a powerful, full-featured instrument for people who want to explore modular synthesis for the first time.


The primary sound generators on the System-1m are a pair of oscillators, a sub-oscillator (1-or 2-octave down), and noise (white and pink varieties available). Each oscillator has six waveform options and can be switched to one of six octaves. They can be modulated from one of six sources (envelopes, LFO, oscillators, or manually), cross-modulated, or ring-modulated together. With the Version 1.2 firmware, you can access six new waveforms for each oscillator—FM, FM+Sync, Noise Saw, Logic Operation, Vowel (formant-style synth), and CB (percussive sound)—and store up to 64 presets.

The Color knob works with each oscillator’s manual setting, and the results depend on the chosen waveform. For example, with a pulse wave, the Color control alters the duty cycle, whereas with saw-wave 2 and square-wave 2 you get a rich, detuning sound that can be used fatten up the timbre of a patch. Hard sync is also available.


The LFO provides six waveforms (including random) with controls over pitch, filtering, rate, fade time (the rate required for the waveform to reach its full level), and amplitude. Furthermore, the LFO can be set to trigger when a key is pressed. The Mixer provides level controls for each sound source with a switch nearby for setting Legato and performance modes (Mono, Unison, or Poly).

As with old-school Roland synth modules, the Pitch, Filter, and Amp sections use faders to set the envelope segments. In addition to the 2-stage (attack, decay) Pitch envelope, you get controls for Portamento and for the initial pitch change (e.g., whether the pitch is momentarily raised or lowered when it’s first struck).

The filter section has a 4-stage envelope generator, and frequency cutoff controls for the high-pass and lowpass filters. You’ll also find a switch to set the lowpass filter to 2-pole (12dB/octave) or 4-pole (24dB/octave) behavior, and controls for setting resonance, key follow, and positive or negative envelope depth. The result is a great deal of flexibility, whether you’re creating acoustic instrument emulations (I love Key follow for this) or highly details synth sounds. Similarly, the VCA has an ADSR envelope generator, with an overall Tone control and main output control nearby.

The digital effects are nice to have onboard and include a bit crusher, reverb (with amount knob), and a delay offering control over amount and time. The knobs and faders throughout the synth feel solid.



The top panel gives you access to the system controls you’ll regularly use, such as buttons for LFO Key Trig, Tempo Sync, memory Write, and a Pitch/Gate knob that triggers a note, based on its setting, when pushed. A 3.5mm stereo headphone jack and USB port sit at either end.

In between, however, you’ll find the fun stuff. Each of the main blocks of the synth architecture has a collection of 3.5mm jacks for externally patching audio (colored red) and CV signals (colored blue), which, in some cases, overrides internal connections. Oscillators 1 and 2, as well as the LFO have dedicated outputs. You can take a pulse from Oscillator 1 to use externally for sync, as well as accept a sync signal for Oscillator 2, which works when the Sync button is engaged. (It syncs to Oscillator 1 when no external input is present.) When the Ring button is lit, an external signal sent to the Ring input subtly ring modulates against Oscillator 2 (not Oscillator 1 as noted in the manual).

You can also run an external signal into the System-1m for filtering and processing through the effects. In this case the sub-oscillator level control adjusts the input signal. The Mix output gives you a mono output directly from the mixer (before it hits the filter, VCA, and effects).

Other CV options include inputs to control the Pitch envelope and the cutoff frequency and LFO modulation for the filter, a gate input for the VCA, and separate envelope inputs and outputs for the ADSRs of the filter and amp.

The astute modular user will have noticed a lack of CV control over the oscillators (other than sync) and the LFO, as well as the limited ability to create feedback paths. Power patchers will no doubt wish for voltage control over such parameters as the Cross Mod, Color, and filter resonance controls. Those would be useful additions, but they don’t fit this semi-modular design and are hardly a deal killer, considering what you do get with the System-1m.



If you don’t have the space in your Eurorack, no problem: The System-1m works as a standalone module with the included power supply. It easily integrates with your DAW, and the USB port supports audio and MIDI.

Fig. 2. The top of the System-1m provides MIDI I/O, stereo 1/4” output, and the DC input and power switch. If you rack the module and lose access to these connections, no problem: You’ll find MIDI I/O on the back and audio outputs on the front, and you can power the unit from your Eurorack case or from a powerstrip. Roland’s clever positioning of I/O and power connectors helps accommodate the many ways the System-1m can be used. In addition to the front-panel 3.5mm audio outputs, a recessed area on the top edge holds left and right 1/4" audio outputs, MIDI I/O, the power switch and AC adapter receptacle, all of which easily supports desktop use (see Figure 2).

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For rack mounting purposes, a second set of MIDI I/O is included on the rear panel. Roland includes rack-ears for mounting the System-1m in a 19" rack, and screws for mounting the synth into a Eurorack case. A special adapter for a Eurorack power bus is also included, along with three 3.5mm patch cables; this is great for starting out, but you’ll eventually want more cables.

The most remarkable thing about the System-1m is that it offers a wealth of musically useful features at its price point, especially when you compare it to other Eurorack or desktop synth modules. But there is no fair comparison: The System-1m is unique as a semi-modular, MIDI-controllable 4-voice synth that also holds a Plug-Out soft synth that you can call up at the touch of a button.

The current list of Plug-Out instruments, all of which utilize Roland’s ACB technology, includes replicas of the SH-101, the SH-2, System-100, and the ProMars Compuphonic synth (featuring dual VCOs and dual sub-oscillators). And don’t forget that your Plug-Out synths can also be used as Audio Units and VST plug-ins within your DAW.

No matter what musical genre you’re in, or whether your work revolves around a keyboard controller, a drum machine, a DJ setup, or a DAW, the System-1m can be adapted to any workflow while continuing to provide expressive synth sounds that range from classic analog emulations to over-the-top modern sounds. Impressive!


Easy to use. USB MIDI and audio. Plug-Out synth host. MIDI I/O. CV/gate control. Works on desktop or in a rack.


No arpeggiator. No Scatter effects. Limited CV control over parameters.