Polyphonic Synthesizer

VAPoly is a virtual analog 8 voice polyphonic synthesizer for iPhone, iPad and Mac. VAPoly features built-in effects, built-in sequencer, parameter automation and oscilloscopes. VAPoly can be used as a stand alone or as an Audio Unit Extension (AUv3).  Stand Alone supports Ableton Link, Bluetooth MIDI, MIDI IN/OUT and audio file export. Project files can be saved in iCloud Drive, so that you can work on a project on iPhone, iPad or Mac whichever is convenient for you at the time.


The synth features two oscillators, two ADSR envelopes, a high pass filter, a low pass filter and an amplifier per voice. The oscillators are capable of wide variety of modulation to shape the sound. The low pass filter is modeled on cascaded OTA filter circuit for classic analog sound.


The Effects includes delay, chorus, flanger, reverb, eq, and compressor.


The sequencer allows you to program 16 bar pattern per clip and you can have total 16 clips. 

Main Features


  • Virtual analog 8 voice polyphonic synthesizer


  • 16 bar patterns per clip. Total 16 clips.
  • Parameter automation.

Audio Export

  • Linear PCM format (AIFF, WAV and CAF) and compressed format (AAC)


  • Support iCloud Drive.
  • Support Ableton Link, Bluetooth MIDI, MIDI In / Out.
  • Support Audio Unit Extension (AUv3)
  • Works on iPhone, iPad and Mac.

System Requirements

  • iOS 15.2 or later
  • macOS 12.1 or later
  • For iOS Devices, A10 Fusion or above is recommended.
  • AudioUnit Extension (AUv3) requires host application which support AudioUnit Extension.
  • AudioUnit Extension (AUv3) is supported by Apple Garage Band on iOS and macOS, and Apple Logic on Mac.  For any other DAW, it depends on the application and some of them don’t support AudioUnit Extension (AUv3).
  • *Apple, Mac and GarageBand are trademarks of Apple Inc., registered in the U.S. and other countries.
  • *Ableton and Link are trademarks of Ableton AG.
  • *All products, companies and standard names are trademarks or registered trademarks of their respective holders.
  • * Ableton Link requires Local Area Network connections.

VAPoly is available now on the Apple App Store.


User Guide (V1.0.5)



8 voice virtual analog polyphonic synthesizer


  • Continuously variable wave shape (triangle, sawtooth, square)
  • Sub: Square, one octave lower (oscillator 1)
  • Pulse width for triangle and square (oscillator 1)
  • Pulse width for square (oscillator 2)
  • Hard Sync (oscillator 1 to oscillator 2)
  • Keyboard on/off (oscillator 2)
  • Low frequency mode (oscillator 2)
  • Tuning +/- 24 semitones
  • Fine tuning +/- 50 cents (oscillator 2)


  • Wave shape: sine, saw, down saw, square, triangle, random
  • Frequency Range:  From 0.04Hz to 42.2Hz
  • Amplitude modulation by ADSR envelope

ADSR Envelope

  • Attack time:    From1ms to 6 sec
  • Decay time:    From 1ms to 10 sec
  • Sustain level:  From 0 to 100%
  • Release time: From 1ms to 10 sec


  • LFO:   frequency, shape, pulse width, amplitude
  • Env:    frequency, shape, pulse width, LFO amplitude
  • Xmod: frequency and shape
  • Ring:   oscillator 1 output and oscillator 2 output
  • Frequency modulation mode: linear / exponential


  • High pass filter: -12 dB per octave
  • Low pass filter: -12 dB per octave / -24 dB per octave
  • Filter envelope: ADSR
  • Frequency modulation by LFO
  • Key Follow


  • Envelope: ADSR
  • Amplitude modulation by LFO


  • Modulation Wheel
  • Pitch Bend Wheel


  • Loop Length: from 1 bar to 16 bars
  • Clip:               16 clips
  • Tempo:           from 20 BPM to 999 BPM
  • Host Sync:     On and Off


  • Delay, Chorus, Flanger, Reverb, EQ and Compressor

*Appearance and specification of products are subject to change without notice.

Release Note

Version 1.0

  • Initial release

Version 1.0.1

  • Fix a problem that notes played on keyboard are terminated at the end of the loop length when internal / external sequencer is running.
  • Fix a problem that notes hangs frequently when playing internal keyboard.
  • Fix problems which make AUv3 to fail the test of AudioUnit Validation Tool on macOS.

Version 1.0.2

  • Fixed a problem that octave range of the piano doesn’t reset when file-New command is called.
  • Fixed a problem that delay time value is set incorrectly when file-New command is called
  • Fixed a problem that font size of the tab labels are not scaled properly.
  • Fixed a problem that font size of the dial labels and switch labels are not scaled properly.
  • Fix a problem that some of the notes played on keyboard in Unison Mode are terminated at the end of the loop length when internal / external sequencer is running.
  • Fix a problem of glide in unison mode.
  • Fix a problem of the  recording count in when Ableton Link is enabled.
  • Fix a problem of editing note  length while recording.
  • Fix a problem of synth button on iPhone.
  • Fix a problem that bar is progressed incorrectly on iOS.
  • Support iOS 16 / iPadOS 16

Version 1.0.3

  • Added Spectrum Analyzer and Spectrogram.
  • Added Pink Noise.
  • Added Polyphonic Glide.
  • Added new effect routing from delay and chorus to reverb.
  • Added LFO Key Re-Trigger switch.
  • Added Master Slider.
  • Added overview to automation editor.
  • Added an option for Quick Look to audition exported audio.
  • Added ability to select MIDI input source in stand alone.
  • Added indicator of selected bar.
  • Added an option to disable sequencer.
  • Improved DSP performance.
  • Improved editing functions of piano roll editor.
  • Improved editing functions of automation editor.
  • Improve velocity mode of internal keyboard.
  • Improved undo and redo.
  • Improved frequency response of the VCF Lowpass Filter.
  • Fixed font size scaling for iPhone.
  • Fixed window scaling of iPhone.
  • Fixed behavior of size parameter of reverb effect when sync is enabled.
  • Fixed a problem that playback doesn’t start from loop start when length of clips are different.
  • Fixed problems of MIDI CC mapping.
  • Fixed a problem of processing MIDI events while sequencer is running.
  • Fixed a problem that holding keys by external MIDI keyboard can’t be turned off.
  • Fixed a problem of arpeggio.
  • Update Ableton Link Framework to the latest version.

Version 1.0.4

  • Fixed a problem that UI doesn’t change when keys in keyboard are pressed.

Version 1.0.5

  • Fixed a problem that value of mod wheel when controlled by external device is incorrect.
  • Support iOS 17 / iPadOS 17.
  • Support macOS Sonoma 14.