Roland AIRA Compact S-1 Tweak Synthesizer Review

The 2023 take on Roland’s classic SH-101 fits in your jacket pocket and only costs $200

The Roland S-1 Tweak Synthesizer is the latest offering from their popular AIRA Compact line of pocket battery-powered, interconnectable modules.

One of the top wishlist items in my recent review for the Cre8Audio West Pest was a built-in battery for use while traveling. While the Roland S-1 isn’t in the same semi-modular synth category, it does seem to be a great solution for those looking to take a pocket synth along on a trip.

The Roland S-1 is modeled after the classic Roland SH-101 analog synthesizer, which has established itself as a legendary bass and lead sound source for acid and drum & bass tracks.

Unlike its monophonic predecessor, the S-1 has a 4-voice polyphony, which also makes it well suited for chords and pads.

Among its very impressive features, this very small synth packs in a powerful 64-step sequencer; an arpeggiator; as well as reverb, chorus, and delay effects.

The bottom portion of the S-1 is populated by a number of backlit rubber buttons that can be used to access various functions. They also serve as a small but remarkably playable 2-octave keyboard.

In and out. Connection-wise, the S-1’s USB-C port can be used to power the unit and recharge its internal battery, and also to send and receive audio and MIDI to a computer (but more on this in a bit). The 1/8″ MIDI in and out jacks require separately sold adapters.

1/8″ Sync in and out jacks can be used with other AIRA products or modules that can send and receive sync signals. The Mix In jack is used to bring in another audio source that can be added to the Mix Out, which can be fed to a set of headphones or any analog input.

Unfortunately, external sound sources can not be routed through the S-1’s filter section, nor can their level be adjusted internally.

All these connections make the S-1 an incredibly versatile synth module with a great deal of options for interfacing with other modules, recording software, or a mixing console for live performance.

All of these various knobs and buttons, coupled with the fact that they can all access multiple functions by pressing the Shift button, can make the S-1 seem a tad overwhelming at first. However, after playing with it for a bit, everything begins to feel intuitive rather quickly.

Sound. The S-1 features faithfully modeled SH-101 square, sawtooth, and noise generators as well as a sub-oscillator that can be set to play one or two octaves below the root note for deep textures and earth-shaking basses.

You can sculpt the oscillators further using the filter section, envelope generator, and the LFO. Tinkering with the various settings and diving into the menu options uncovers a multitude of sonic possibilities.

The built-in reverb, delay, and chorus add a final shimmer to the S-1 with stereo depth and dynamic complexity. In the following example I programmed a simple arpeggiated sequence and then switched through different presets to offer an overview of the types of sounds the S-1 is capable of producing. 

If all that wasn’t enough, the S-1 also allows for two custom waveform creation modes that were not on the original SH-101. OSC DRAW lets you “draw” a custom waveform by using the keyboard notes to assign amplitude values to each of the 16 pads. OSC CHOP “chops” the existing waveforms by emphasizing or de-emphasizing various harmonic overtones.

Sequencing. Programming the sequencer on the S-1 is fairly straightforward. After selecting one of the 64 available patterns, either input the notes as steps or use the Record button to perform them in real-time.

The length of each sequence can be extended up to 64 steps. A handy Metronome feature adds a one-bar count-off, and it can be set to play continuously or only during record.

Notes aren’t the only things that be recorded. Most of the parameters, such as CutOff Filter and Resonance, ADSR, and effects can be tracked into the sequencer with some complex evolving patterns.

Every single knob-controlled parameter also sends and receives MIDI CC data, which allows all of the automation goodness one could hope for, even with external devices.

The S-1 also features an Arpeggiator that can be configured for various up/down modes as well as different note values based on the master tempo.

Integration. With its incredibly feature-rich capabilities, I was interested in seeing how well the S-1 would work with an external DAW. Using the USB-C connection straight into my laptop, both my Mac Book Air and Apple Logic Pro instantly recognized the S-1 as an audio and MIDI device.

However, creating a reliable audio and MIDI signal path with the S-1 proved a bit of a challenge, due in part to the rather scant information available in the manual and (quite possibly) user error on my part.

For audio, trying to set up an Aggregate Device in the macOS AudioMIDI Setup utility was an unsuccessful way to retain access to both the S-1 and my other audio interface. (Aggregate devices combine audio interfaces so they appear as a single one with all the ins and outs from each.)

In addition, feeding my MIDI keyboard controller signal to the S-1 created a MIDI feedback loop. It produced some very interesting sounds, but it wasn’t exactly what I was looking for.

Since I was unable to find a local off feature, it seems the issue is that the S-1 echoes incoming MIDI notes back out as if they were being played on its built-in keyboard. Those notes get added into the DAW’s MIDI signal flow, creating an undesired feedback loop. Hopefully, future firmware will address this issue. 

Using the S-1 as the only MIDI/Audio interface attached to the computer solves these pesky issues, but does also restrict its usability within a more complex studio setup.

Finally, there’s the S-1’s D-Motion function. This feature lets you pick up the unit and turn and twist it to affect various parameters in real-time. D-Motion effectively turns the S-1 into a 3-D spatial controller that can be used with itself or to drive other MIDI instruments.

Planes, trains, and automobiles. So how did the S-1 work out for traveling? In a word, great! The S-1 is quite possibly the best portable synth and sequencer I’ve ever used.

I’d often wear Apple Air Pods underneath larger headphones hooked up to the S-1. This weird but functional setup allowed me to jam on the S-1 along with music tracks playing on my phone. The built-in battery lasted well into my flights, and the small size barely takes up any room in a carry-on bag.

Bottom line. The Roland S-1 is a feature-packed powerhouse of a portable synth that seems almost too good to be true for the price. Its SH-101 emulation is spot on, and the engine sounds as rich and complex as much larger (and pricier) synths. Hopefully, Roland will add a local off mode to make interfacing with a DAW easier, but with some minor workarounds the S-1 can still function in a studio environment.

I’m completely sold on the S-1 and would recommend the Roland S-1 to any musician interested in access to a vast array of analog synth sounds in a unit about the size of a small paperback. Here’s to looking forward to whatever Roland releases next in the AIRA Compact series – like a Jupiter-8? Pretty please?

Price: $199

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