Roxsyn Guitar Synthesizer 4+

Metamorphic Synth for Guitar

Yonac Inc.

    • 4.7 • 85 Ratings
    • $19.99



Introducing a revolutionary new way to turn your guitar or bass into a fully featured polyphonic synth: Roxsyn, the world’s first metamorphic guitar synthesizer. Expressive, fast and responsive to every nuance, it is a league apart from all other guitar synths to date.

Unhappy with cold and temperamental guitar-to-MIDI synths that dominate the market, we developed a completely new approach to guitar synthesis. Our all-original technology synthesizes your guitar directly, without the use of MIDI notes. Rescued from being a poor keyboard substitute, your guitar suddenly becomes an integral part of the synth. It's alive!

There is no pitch tracking involved. There are no pitch estimation errors, octave glitches, or garbled chords. There is no over-complicated G2M between your guitar and synth to destroy everything human about your playing. Instead, Roxsyn’s metamorphic sound generation technology retains all the personality of your sound: vibrato, slides, bends, dynamics, even extended technique. The result is a polyphonic synthesizer that is as fast and accurate as it is richly expressive.

No need for special MIDI pickups or hardware, either: just plug into your favorite Lightning/USB audio interface, and start synthing!

::Powerful Synth Engine::

Roxsyn’s big synth heart is its three metamorphic signal generators (AKA oscillators). Each generator offers 5 unique waveforms, and has a 4+ octave range to cover a wide spectrum of frequencies. They also feature stereo panning, and can route into either of Roxsyn’s dual filter banks. You can even dial in your guitar directly into the synth engine for even bigger sounds.

::Dual Filter Banks::

Each containing four custom virtual-analog filter types and dedicated envelopes, the filter banks help sculpt the synth generators in countless new ways. The envelopes are specially designed for the guitar, and are driven by a fully adjustable automatic trigger generator controlled by your playing dynamics. Envelopes offer original features like finite-duration sustain stages, as well as the ability to receive or ignore trigger-off messages. They can also be triggered externally via MIDI controllers like an expression pedal.

An additonal envelope controls the amplitude of the signal, giving you even more options in creating synth sounds.


Instantly transform sustained guitar notes into fast (or slow), complex patterns with Roxsyn’s powerful yet easy to use arp. There are 8 stepping algorithms to choose from, as well as settable note value, swing, and note repeats. You can even route the arp to any combination of the 3 voice generators — enabling you to layer a non-arpeggiated sound with an arp pattern. What's more, the arp can send trigger signals into any of Roxsyn’s 4 envelopes, and even reset the LFOs. So it’s also a handy rhythmic / trance tool as well!

::Modulation & FX::

Roxsyn’s user friendly modulation matrix lets you manipulate parameters (pitch, amplitude, filters, etc) using its two LFOs and mod envelope. Add subtle vibrato, even glide simulation, or go full-on berserk. LFOs each have 9 waveforms, and feature beat syncing. Each matrix row can take LFOs or the mod envelope as a modulator or control, and can even use external control sources.

And if you like your synths on the spicy side, Roxsyn comes with top-notch stereo FX specially developed to evoke extra synthiness: Powerful algorithmic reverb with the sound of countless rooms, phasing, modulating, 2-channel delay, and graphic EQ.

::Pro Features::

500+ factory presets with bass, lead, pad, arp sounds & more. Easily create & share your own presets. Audio Unit v3, Ableton Link. Native 64-bit processing at up to 96kHz. 160+ MIDI controllable parameters; MIDI learn & map save/share; tapedeck (in the standalone app), so you can record, loop & share your ideas on the go, and many more handy features.

What’s New

Version 1.2

• Increases robustness of the MIDI implementation
• Other improvements & fixes

Ratings and Reviews

4.7 out of 5
85 Ratings

85 Ratings

sneJ ,

Better than a $200 pedal

This sounds better than Boss’s much-hyped new $200 synth pedal. The Boss demos/videos I’ve seen all have cheesy ‘80s synth sounds; if I wanted to play those, I’d just use a synth. The special sauce here is that Roxsyn produces more complex, interesting sounds (though it can still sound like Miami Vice if you want that.)
The tracking and polyphony are quite good. Not perfect, but once you tweak the tracking it’s quite easy to play. It does glitch sometimes, but I embrace that as part of the sound. (20 years from now that’ll be “retro” and everyone will be emulating tracking glitches...)

transcendentalaccidentalism ,

Was expecting something useful

Yonac makes some great apps. My favorites are the Steel Guitar Pro and the Galileo 2 in terms of usefulness and the way they fit with other apps and midi control effects in an app like AUM. I don’t have Magellan Synth 2 or the newest Trooper, which I would love to check out, but haven’t found the reason to spend $15 for each yet.

There is a lack of consistent quality guitar interface synths with midi translation that maintain iOS updates. The decent ones seem to suddenly vanish - like midimorphosis.
That being said, that’s not what this app is. In fact there is no midi control function. It’s just a very thick and oozing filtering app that takes a guitar signal and destroys it with effect parameters commonly found on oscillation type synthesizers, with filtering, arping, and all of the other common audio effects, plus lots and lots of distortion.
I have yet to find a use for it honestly, which is weird considering how many presets it has - presets that have very little range. Of you want to go from noisy lower pelagic oceanic deep distorted and modulated reverb to lush distorted low pass filtered arpeggiated offset delays that have no discernible pitch modulation, then there are millions of presets for everything in between those two.
If there were better clean tones, o might be able to use this.

A rare miss imo for Yonac, but you might find it vastly and useful.

Aladdin Wannabe ,

I love the response, but...Developers please add some features

This is the best guitar synth that picks up all the dynamics that other midi guitar synths don’t..It doesn’t have limited sound that gives off like the other apps, its very expressive with stuff like bending notes and vibrato.

I just wish that the voices provided in this app also included saw wave, sine wave etc.

All the sounds start sounding the same after a while.

This app has a lot of potential to have a guitar player/ synthesist change the instrument of a synthesizer. The guitar is way more expressive than the piano because of how human it is to press a note on a fret and have it slightly off pitch when bending it just a little..the piano is so rigid in playing notes..sure they have a pitch wheel but its not as expressive as shaking notes on a guitar with your finger or whammy bar.

If they have the traditional sounds like the sine wave and sawtooth, synthesizer players might consider playing a guitar what if there can be a foot pedal that can allow you to oscillate manually like a wah pedal.

Please add the feature of adding the traditional sine wave and sawtooth, triangle, square etc. voices

App Privacy

The developer, Yonac Inc., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.

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