Parawave Audio Rapid Synthesizer Review


Rapid is an 8-layer morphing wavetable synthesizer with a bright, modern, vivid core sound and massive (if you’ll pardon the pun) potential as a track-wide workstation thanks to the inclusion of complicated modulation and sequencing tools and the addition of scores of multi-sampled instrument sounds.

Each of Rapid’s eight layers is bordering on a self-contained studio of its own. The layers feature three oscillators that can play morphable wavetables or multi-sampled instrument content, one multi-mode filter with 20 models to select from, a polyphonic insert effect that processes each note individually, and seven insert effects for processing the layer’s audio stream. On top of that, there are four envelopes and LFOs, four graphic sequences for all of your zigzagging, squiggly modulation shapes, an arpeggiator or pattern/riff player, and its own 32-slot modulation matrix.

Each one of these elements is brimming with functionality, to the point that adding anything else would infringe usability. Let’s talk about the oscillators, three in number and all with the same options.

Firstly there is the huge amount of wavetables, which are in almost all cases creatively arranged sequences of timbres which you can smoothly glide between while your choice of 2D or 3D graphics demonstrates the shape of the waveform in real-time. These are very bright and alias-free and can be further manipulated with an EQ and Zebra-like oscillator shape modifiers, giving a massive, multi-dimensional sound map right at the sound source. Each of these oscillators can be multiplied, detuned and/or spread across the panorama, and the phase at note-on can be controlled or randomized to a specified degree.

I want to talk briefly about these wavetables – there really are very few boring or same-y ones. They’ve all been devised by someone who is clearly knowledgeable about synthesis and showcase an impressive amount of diversity and usability. These are not just collections of random waves that you can blend between, they all have a logical progression from one wave to the next, whether that be by the stretching and mixing of waveform geometries, harmonic series, synthesis functions in concert, or specific tonal goals one might look for when creating a sound from scratch. It’s also worth noting that the parameter for the wavetable index runs a range from zero to ten thousand! So smoothness is never going to be an issue unless you want it to be.

The oscillator effects feature one or two parameters, often giving you extra oscillators to perform synthesis functions with. For example Phase and Ring Modulation give you an intensity knob, plus an offset pitch to determine the height of the modulating sine wave relative to notes played. Should you want a fixed, arbitrary modulation frequency, the insert effect has you covered.

Hard Sync functions similarly, where the amount knob determines how many cycles of the current wave are “squashed” into the fundamental wavelength, while also tapering the waveform at the beginning and end of the cycle to avoid harsh transitions, providing a very “vocal formant” type of motion. Phase Bend, which bends the geometry of the wave to produce PWM-type effects with any waveform, Chaos Phase, which adds jitter to the pitch of the sound, and Noise Generator, which blends an adjustable noise signal with the sound, are some of my favourites, but there are more; and these functions provide a quick way to get at more advanced synthesis techniques without requiring lots of screen real estate.

This set-up, combined with the abundant wavetables and samples, also mean that those new to synthesis can quickly experiment with different combinations rapidly, without having to tie in dedicated modules to the process. No wonder the synth is called “Rapid”!

The filters and effects slots offer a lot of choices. In particular, I like the fact that some of the filters have their own unique controls such as Feedback and Width, meaning that many of the filters do different things rather than just having different response profiles. The LFOs also have a rich diversity of wave shapes you can utilize, and you can blend two waves together in any amount, allowing a great deal of expressibility when you modulate this parameter.

Speaking of modulation, you can modulate anything. As far as I can tell, if you see something – an effect parameter, the EQ on an oscillator, envelope parameters – anything – you can modulate it; either by patching it in manually via the Mod Matrix, or by the use of the “Route” and “Modulate By” options which pop up when you mouse-over or right-click a knob.

Modulation feedback is provided by coloured lines around each knob, which detail both the total range of modulation assigned and the current modulation amount simultaneously. Little touches like this, the built-in oscilloscope/level meter, the tooltips, and the clear, orderly layout make using Rapid an absolute blast in my opinion.

Rapid’s core sound is clean and full, very hi-fi and modern sounding, but with such an ease of tweakability that anyone familiar with synthesis or willing to experiment will be able to navigate an endless sea of sound possibilities… and the eight layers (which can be copied and pasted, muted, mixed and ran through a global multi-band compressor) allow complex grooves and generative soundscapes to be produced with the minimum of barriers.


For me, there is very little to dislike about Rapid. It’s a “master of all trades” synthesizer with a workstation bent, allowing you to blur the lines between sound design, mixing and sequencing. For those just starting out, Rapid could fill a lot of niches very quickly, and to the more experienced it’s something to reach for when you’re in the zone and just need to get working with high-quality sound. The amount of features that are packed into this beast constantly surprises me, and it remains effortless to use.

More info: Rapid Synthesizer (€179.99)
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Rapid Synthesizer Review


There is very little to dislike about Rapid. It's a “master of all trades” synthesizer with a workstation bent. For those just starting out, Rapid could fill a lot of niches very quickly, and to the more experienced it's something to reach for when you're in the zone and just need to get working with high-quality sound.

  • Features
  • Workflow
  • Performance
  • Design
  • Sound
  • Pricing
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About Author

Sendy has been making music in her bedroom since she was 14 using computers, synthesizers, samplers, and whatever else was at hand. She does not subscribe to any one genre but enjoys energetic, constantly changing rhythms, disorienting synthesizer manipulations, and heroic chiptune melodics.


  1. Great stuff! I wonder if they are planning import of wavetables in this version upgrade or in version2. My question is – to buy it today or wait….? What do you think?

    • There is talk of sample and wavetable import in an update. I know they are planning to sell expansions, which I think would be quite good, but can’t say for sure.

  2. I’m always exited when i see Sendy’s name on a review. :) She knows her stuff it seems. ;)

    Btw, this one looks like a monster synth. And wavetables, my favorite!

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