Step Polyphonic Arpeggiator/Sequencer For iOS

StepPolyArp Unit can generate melodic patterns from played notes or chords      07/06/18

Its designer, Laurent Colson, describes StepPolyArp Unit as a real-time polyphonic and polyrhythmic MIDI step arpeggiator and step sequencer. It can be used as a standalone application or an Audio Unit MIDI effect plug-in. This is his full description of it:

The application and the plug-in can operate as a step arpeggiator by automatically generating melodic patterns from played notes or chords, or as a step sequencer that doesn't require MIDI input to play.

Unlimited presets can be saved on a local device and synchronized to iCloud. Each preset contains 16 patterns, 5 customizable polyrhythmic step controllers, and a 32 steps event matrix with 11 polyphonic and polyrhythmic lines driving the arpeggiator engine.

The application supports full internal and external MIDI connections for input and output, Audiobus MIDI sender, MIDI filter routing, Ableton Link sync, and MIDI clock source sync. An internal sound bank is included.

The Audio Unit MIDI effect plug-in supports multiple instances. A compatible host is required to run the plug-in. The host needs to support the Audio Unit MIDI effect format.


• Standalone application and Audio Unit MIDI effect plug-in
• Arpeggiator and step sequencer mode
• 1 to 32 steps programmable matrix
• 11 configurable transposition lines
• Polyrhythmic lines
• 16 patterns by preset
• Automatic chaining patterns
• 8 octaves resizable keyboard
• Multitasking
• Sample-accurate timing
• Internal sound bank
• Tap tempo
• Receiving MIDI from external MIDI sources
• Receiving external MIDI sync (MIDI clock)
• Ableton Link support
• Internal routing of inputs, outputs, and MIDI sync
• Send MIDI to a virtual port that can be used as MIDI input by other "Core MIDI" compatible applications
• Default velocity, modulation, pan, volume, aftertouch, and pitch bend steps controller
• Customizable steps controller MIDI setup
• Arpeggiator and sequencer conform to the selected scale
• 6 arpeggiator modes
• 1 random mode
• 1 chord mode
• Random patterns creation
• Presets manager
• "Program Change" support
• Native iCloud support
• "Files" application support
• Full support of "Split View" and "Slide Over"
• 128 Undo / Redo levels
• Copy and paste
• Lockable keyboard (latch mode)

Compatible hosts supporting Audio Unit MIDI effect:

• Cubasis

Supported MIDI connections:

• Virtual "Core MIDI" connections between applications
• iOS compatible MIDI interface
• MIDI over Wifi
• MIDI over Bluetooth
• Ableton Link (sync and transport)
• Audiobus (MIDI, transport, state saving)


An iPad or iPhone with iOS 11 or later

Pricing and Availability:


More information:





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