Review: Zeeon – a State of the Art Synthesizer App for the iPad

If you are searching for a leading edge iOS virtual analog synth that also works as AU plugin, look no further than Zeeon. The latest release from BeepStreet, purveyors of another excellent iOS synth, Sunrizer, and the very cool drum synth, Impaktor, this is a high quality music app that immediately rises to the top of the iPad synthesizer scene. It features a deep sound engine, straightforward interface, and – AU support!

Zeeon for the iPad Features

  • Two Variable Waveform Oscillators with Hard Sync and Sub Oscillator
  • Three Filter Models – Ladder Style, OTA Cascade Low Pass, State Variable
  • Two LFOs and EGs per Voice
  • Monophonic, Polyphonic, and Unison Modes
  • Pre and Post Filter Overdrive Circuit
  • Two Separate Voice Layers with Cross Modulation
  • Robust Modulation Matrix
  • Effects include Delay, Reverb, Phaser, Chorus, and Bass Booster
  • Excellent User Interface
  • AU Support and Standalone Mode with a Bare-bones Step Sequencer
  • 144 Inspirational Presets
  • Available at the App Store for $9.99

Simply put, Zeeon is a must-have synth app for iOS users. Its user interface, sonics, and architecture are all top notch. Let’s dive into a few details!

An iPad Analog Synthesizer worthy of your Attention

Zeeon’s interface should make any veteran subtractive synthhead feel at home. The left side of Panel 1 lets you navigate between the two synth layers, as well as access a second screen (“Panel 2”) with effects and other voice parameters. It also has a cool virtual oscilloscope offering a real-time view of the current waveform, while also providing access to the patch library.

Zeeon image-1

Panel 1 contains the meat of Zeeon’s synth architecture. Screenshot by author.

The rest of Panel 1 includes sections for the oscillators, a mixer, filter and envelopes, LFOs and the drive circuit, as well as a modulation matrix. A virtual keyboard and step sequencer are also useful when using Zeeon in standalone mode, which is where I’m currently at musically, doing overdubs on the next Church of Hed album. The virtual knobs and switches render well and perform as expected on the iPad’s touchscreen.

A Robust Subtractive Synth Architecture

Zeeon is based on a standard subtractive synth architecture with a host of cool features, most notably a high-end analog circuit modeling engine, leading to its stellar sound quality. Additionally, the waveforms are continuously variable, which makes them highly suitable as targets in the modulation matrix. The engine also simulates real-world analog circuitry, including transistor saturation, oscillator drift, and the influence of the power supply. Thankfully, it stays in tune!

Two separate synth layers lend themselves to cross-modulation possibilities. The interface also supports copying between the two layers, which is useful when in sound design mode. Speaking of which, the robust modulation matrix lets you execute pretty much any weird sonic idea you desire.

Zeeon image-2

Effects and other fun stuff reside on Zeeon’s Panel 2. Screenshot by author.

When it comes to Zeeon, what’s not to like? Three different filter models, a useful effects engine, a drive circuit, and so much more. Preset surfing is a blast, and usually triggers an inspiration for a new patch idea of your own.

Its support for the AU plugin format is essential. (For iOS music app reviews at TabMuse, I expect to focus only on those apps supporting AU moving forward.) I can’t wait to finish my current album, so I can start beatmaking, and using Zeeon in Modstep or Beatmaker 3. The step sequencer in standalone mode is barebones but still useful when auditioning a patch.

Zeeon ranks near the top of iOS synth apps, which is all the more impressive considering BeepStreet isn’t a famous hardware synthesizer company. This is one of the easiest recommendations we’ve ever made at TabMuse. Run out and git ya some!


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